{"collection":"scripture-revelation","full_text_available":true,"graph_url":"https://unchartedknowledge.5gfusion.net/v2/api/page/gutenberg_39566/graph","html_url":"https://unchartedknowledge.5gfusion.net/v2/page/gutenberg_39566","id":"gutenberg_39566","license":"Public Domain (US)","rights_basis":"gutenberg_metadata_copyright_false","source":"gutenberg","source_url":"https://www.gutenberg.org/ebooks/39566","summary":null,"tags":["Category: Philosophy & Ethics","Category: Religion/Spirituality","Category: Science - Physics","Heat","Religion and science"],"text":"E-text prepared by the Online Distributed Proofreading Team\n(http://www.pgdp.net) from page images generously made available by\nInternet Archive (http://archive.org/)\n\n\n\nNote: Project Gutenberg also has an HTML version of this\n      file which includes the original illustrations.\n      See 39566-h.htm or 39566-h.zip:\n      (https://www.gutenberg.org/cache/epub/39566/pg39566-images.html)\n      or\n      (https://www.gutenberg.org/files/39566/39566-h.zip)\n\n\n      Images of the original pages are available through\n      Internet Archive. See\n      http://archive.org/details/curiositiesofhea00teff\n\n\n\n\n\n[Illustration: EFFECT of HEAT.\n\nFrontispiece.]\n\n\nCURIOSITIES OF HEAT.\n\nby\n\nREV. LYMAN B. TEFFT.\n\n\n\n\n\n\n\nPhiladelphia:\nThe Bible and Publication Society,\n530 Arch Street.\n\nEntered according to Act of Congress, in the year 1871, by\nThe Bible and Publication Society,\nIn the office of the Librarian of Congress, at Washington.\n\nWestcott & Thomson,\nStereotypers, Philada.\n\n\n\n\nCONTENTS.\n\n\n                                              PAGE\n\n  CHAPTER I.\n\n    MR. WILTON'S BIBLE CLASS                     7\n\n  CHAPTER II.\n\n    NEW THOUGHTS FOR THE SCHOLARS               26\n\n  CHAPTER III.\n\n    A DIFFICULT QUESTION                        58\n\n  CHAPTER IV.\n\n    HEAT A GIFT OF GOD                          83\n\n  CHAPTER V.\n\n    CONVEYANCE AND VARIETIES OF HEAT           100\n\n  CHAPTER VI.\n\n    MANAGEMENT AND SOURCES OF HEAT             120\n\n  CHAPTER VII.\n\n    PRESERVATION AND DISTRIBUTION OF HEAT      152\n\n  CHAPTER VIII.\n\n    MODIFICATION OF TEMPERATURE                176\n\n  CHAPTER IX.\n\n    THE MINISTRY OF SUFFERING                  190\n\n  CHAPTER X.\n\n    TRANSPORTATION OF HEAT                     213\n\n  CHAPTER XI.\n\n    AN EFFECTIVE SERMON                        233\n\n  CHAPTER XII.\n\n    TRANSFER OF HEAT IN SPACE                  254\n\n  CHAPTER XIII.\n\n    OCEAN CURRENTS AND ICEBERGS                272\n\n  CHAPTER XIV.\n\n    COMBUSTION.--COAL-BEDS                     292\n\n  CHAPTER XV.\n\n    ECONOMY OF HEAT                            305\n\n  CHAPTER XVI.\n\n    A DAY OF JOY AND GLADNESS                  320\n\n\n\n\nCURIOSITIES OF HEAT.\n\n\n\n\nCHAPTER I.\n\nMR. WILTON'S BIBLE CLASS.\n\n\n\"The book of Nature is my Bible. I agree with old Cicero: I count Nature\nthe best guide, and follow her as if she were a god, and wish for no\nother.\"\n\nThese were the words of Mr. Hume, an infidel, spoken in the village store.\nIt was Monday evening. By some strange freak, or led by a divine impulse,\nhe had determined, the previous Sunday afternoon, to go to church and hear\nwhat the minister had to say. So the Christian people were all surprised\nto see Mr. Hume walk into their assembly--a thing which had not been seen\nbefore in a twelvemonth. Mr. Hume did not shun the church from a dislike\nof the minister. He believed Mr. Wilton to be a good man, and he knew him\nto be kind and earnest, well instructed in every kind of knowledge and\nmighty in the Scriptures. He kept aloof because he hated the Bible. He had\nbeen instructed in the Scriptures when a boy, and many Bible truths still\nclung to his memory which he would have been glad to banish. He could not\nforget those stirring words which have come down to us from the Lord\nJesus, and from prophets and apostles, and they sorely troubled his\nconscience. He counted the Bible an enemy, and determined that he would\nnot believe it.\n\nAt that time there was an increasing religious interest in the church. Mr.\nWilton had seen many an eye grow tearful as he unfolded the love of Christ\nand urged upon his hearers the claims of the exalted Redeemer. He found an\nincreasing readiness to listen when he talked with the young people of his\ncongregation. The prayer-meetings were filling up, and becoming more\ninteresting and solemn. The impenitent dropped in to these meetings more\nfrequently than was their wont. Mr. Wilton himself felt the power of\nChrist coming upon him and girding him as if for some great spiritual\nconflict. His heart was filled with an unspeakable yearning to see\nsinners converted and Christ glorified. He seemed to himself to work\nwithout fatigue. His sermons came to him as if by inspiration of the Holy\nSpirit. He felt a new sense of his call from God to preach the gospel to\nmen, and spoke as an ambassador of Christ, praying men tenderly,\npersuadingly, to be reconciled to God, yet as one that has a right to\nspeak, and the authority to announce to man the conditions of salvation.\n\nA few of the spiritual-minded saw this little cloud rising, but the people\nin general knew nothing of it. Least of all did Mr. Hume suspect such an\nundercurrent of religious interest; yet for some reason, he hardly knew\nwhat, he felt inclined to go to church.\n\nThat afternoon the preacher spoke as if his soul were awed, yet lifted to\nheavenly heights, by the presence of God and Christ. Reading as his text\nthe words, \"Thou thoughtest that I was altogether such an one as thyself\"\n(Ps. l. 21), he showed, first, the false notions which men form of God,\nand then unfolded, with great power and pungency, the Scripture revelation\nof the one infinite, personal, living, holy, just, and gracious Jehovah.\nThis was the very theme which Mr. Hume wished most of all not to hear.\nThat very name, Jehovah, of all the names applied to God, was most\ndisagreeable; it suggested the idea of the living God who manifested\nhimself in olden time and wrought wonders before the eyes of men. But the\ninfidel, with his active mind, could not help listening, nor could he\nloosen his conscience from the grasp of the truth. Yet he could fight\nagainst it, and this he did, determined that he would not believe in such\na God--a God who held him accountable, and would bring him into judgment\nin the last great day. In this state of mind he dropped into Deacon\nGregory's store.\n\nDeacon Gregory was accustomed to obey Paul's injunction to Timothy: \"Be\ninstant in season, out of season; reprove, rebuke, exhort with all long\nsuffering and doctrine.\" Having taken Mr. Hume's orders for groceries, he\nsaid, \"I was glad to see you at church yesterday, Mr. Hume. How were you\ninterested in the sermon?\"\n\n\"I like Mr. Wilton,\" answered Mr. Hume; \"I think him a very earnest and\ngood man.\"\n\n\"But were you not interested and pleased with the discourse? It seems to\nme that I shall never lose the impression of God's existence and\ncharacter which that discourse made upon me. I almost felt that Mr. Wilton\nspoke from inspiration.\"\n\n\"I suppose he was inspired just as much as the writers of that book which\nmen call 'the Bible.'\"\n\n\"But can you wholly get rid of the conviction that the Bible is the word\nof God, written by holy men inspired by the Holy Spirit?\"\n\n\"You know, Deacon Gregory, that I do not believe what you profess to\nbelieve. The book of Nature is my Bible. I agree with old Cicero: I count\nNature the best guide, and follow her as if she were a god, and wish no\nother.\"\n\nDeacon Gregory had never read Cicero, and of course did not attempt to\nshow, as he might otherwise have done, that Cicero did not mean to deny\nthe existence of a living, personal God, who governs the world.\n\n\"But,\" said he, \"does not the book of Nature--your Bible, as you call\nit--have something to say of God? Does it not speak of an infinitely wise\nand good Creator and Governor? Do not the works of Nature tell of the same\nGod whose being and character were preached to us yesterday from the Holy\nScriptures?\"\n\n\"Nature has never spoken to me of any God except herself. What need is\nthere of a creator? Who can prove that the universe did not exist from\neternity? Nature has her laws of development, and under those laws all the\noperations of nature go on. You had better read Darwin. If one must find\nthe character of God in nature, he may as well picture an evil creator and\ngovernor as one that is good and righteous. Does Nature punish those whom\nyou call the wicked? Does Nature reward the righteous? Do not the laws of\nNature bring suffering to the good and the bad alike, and happiness also\nto all classes of men? Would you, if you had power, create a world like\nthis--a world in which danger, pain, and death, in every shape, lie in\nambush against its inhabitants every hour of their poor existence? But I\nmust go.\" Pausing a moment, however, as if reluctant to go, with a voice\nsad and almost tremulous, which revealed a great deal more of his heart\nthan he designed to express, he added: \"God knows, deacon, if there be a\nGod, how I wish I knew the truth about these matters. The world and myself\nare to me great and dreadful mysteries.\"\n\n\"'He that will do his will shall know of the doctrine,'\" answered Deacon\nGregory; and inviting him to come to church again, they separated.\n\nThis conversation with the pious deacon, though he had himself done most\nof the talking and had his say almost unopposed, did not tend at all to\nbring rest to Mr. Hume's conscience. He saw that the deacon's faith in God\ndid for him more than belief in Nature and worship at the altar of Science\ncould do for unbelievers. He felt also that he had spoken a little too\nfreely, especially in revealing, at the last, his unrest of spirit from\nthe want of fixed convictions in regard to religious truth. Deacon\nGregory, by the sincerity and manliness of his address, was accustomed to\ndraw out the hearts of men so that they expressed them more freely than\nthey designed.\n\nUpon a bench in a shaded corner of the store sat a lad of sixteen or\nseventeen years, unnoticed for the time being by either Mr. Hume or Deacon\nGregory. His name was Ansel, and he was the son of the senior deacon of\nthe church. He was in the village academy, and had there been nearly\nfitted for college. He stood at the head of his class, and, with his sharp\nintelligence, his impetuous energy, and high ambition, every one was\npredicting for him a distinguished life. He had grown up thus far in the\nbosom of a family where piety was no pretence. Earnest prayer had gone up\nfor him by day and by night. He had been well trained in the\nSunday-school, and for a year had been a member of the small class of\nyoung men taught by Mr. Wilton. He had always shown a ready interest in\nall Bible studies and a quick understanding of Scripture doctrine, so that\nsome thought him not far from the kingdom of God. But Deacon Arnold little\nthought what was in the heart of his son. He might have known, for to\nread his son's heart he had only to recall his own early manhood. For\nyears he had hung trembling upon the brink of ruin, swept, at times,\nby his self-will and turbulent youthful passions, to the very verge\nof the precipice, and had been preserved only by singular grace\nfrom falling over. Now Ansel was following in his father's early\nfootsteps--self-willed, and stubborn against the Spirit of God, and, at\ntimes, almost persuaded to cast off all religious restraint, that he might\ncarve out his worldly fortunes untrammeled by religious or conscientious\nscruples. He had rarely heard infidel sentiments expressed, but the little\nthat he had heard had attracted him, and had encouraged him to give loose\nreins to his own unbelieving disposition. It had not escaped his notice\nthat the two or three men whom he had heard spoken of as infidels were\namong the most respectable and shrewdest business-men in the village. The\nidea, moreover, of rejecting all authoritative doctrine, and believing\nwhatever should please him, carried with it so free and independent an\nair, and harmonized so well with his natural disposition, that he easily\ndrifted in the direction of unbelief.\n\nSitting this evening unobserved, he drank in every word which Mr. Hume\nuttered. Some of the notions thrown out were quite new to him. \"The book\nof Nature my Bible\"--\"Nature reveals no God but her own laws\"--\"No proof\nthat the matter of the universe has not existed from eternity\nuncreated\"--\"Nature has her laws of development\"--\"No need of a God to\ngovern the world,\"--these were seed-thoughts in Ansel's mind. He had\nbefore thought of the only alternative to be set over against belief in\nthe sacred Scriptures as simply unbelief--bare, blank denial of their\ntruth. He had not dreamed of building up a set of proud, rationalistic\nnotions, and denying the truths of religion in the character of a young\nphilosopher. He kept his thoughts to himself, and turned them over and\nover in his mind during the week, and when again he met his pastor in the\nBible class his head was full of his new notions. The lesson went on,\nhowever, and closed as usual. It so happened that this was the last in a\nseries of lessons upon the Gospel of John. It was necessary, therefore,\nthat another course of lessons should be decided upon.\n\nMr. Wilton proposed the question to the class: \"What shall be our next\ncourse of lessons? Would you like to study one of the Epistles--the\nEpistle to the Romans or that to the Hebrews?\" And he briefly stated the\nsubject discussed in these Epistles of Paul. \"Perhaps,\" he continued, \"you\nwould prefer to study one of the historic books of the Old Testament?\" The\nclass had no opinion. They wavered between an Epistle and a historic book\nand topical lessons which should confine them to no one book of the Bible.\nThen Ansel spoke up:\n\n\"Mr. Wilton, why can we not study something which we know to be true?\"\n\nAnsel meant to be very cautious as well as very respectful, and did not\ndesign to commit himself by suggesting his own thoughts. He was\nrespectful, but in the confusion of the moment he had brought out the very\nthoughts which he meant to conceal.\n\nMr. Wilton was startled, though he did not fully understand the drift of\nAnsel's question.\n\n\"What do you mean, Ansel?\" he asked; \"do you think Genesis less\ntrustworthy than the Epistle of Paul?\"\n\nAnsel saw that he had committed himself and must now make the best of his\nsituation. He therefore answered cautiously:\n\n\"Some persons, I have heard said, do not believe the Bible to be inspired,\nand they say that we have no evidence that it is true.\"\n\n\"What have you been reading, Ansel, that has put such thoughts into your\nmind?\"\n\n\"I have never read a book that said anything against the Bible.\"\n\n\"But what did you mean? Do you wish to study the evidences of the truth\nand inspiration of the Holy Scriptures?\"\n\n\"I should indeed like a course of lessons upon that subject, but that was\nnot quite what I was thinking of.\"\n\n\"What book can you find which is true if the Bible is not true?\"\n\n\"I do not know, sir, but I heard Mr. Hume say that the book of Nature is\nhis Bible, and that we do not need any other, and that, whether the Bible\nbe true or not, we know that the teachings of Nature must be true.\"\n\n\"But we should find,\" said Mr. Wilton, \"that the teachings of Nature and\nthe Bible would perfectly agree. Did Mr. Hume say that what he calls 'The\nbook of Nature' contradicts the sacred Scriptures?\"\n\nNow that Ansel could give the thoughts which filled his mind, not as his\nown, but as Mr. Hume's, he showed no farther hesitation in speaking.\n\n\"Yes, sir,\" he answered; \"he said that Nature teaches us that there is no\nGod, because there is no need of any. He said that we cannot prove that\nGod created the universe, but that matter has existed from eternity\nuncreated, and that all the changes in nature go on by certain laws of\ndevelopment, and that a certain Mr. Darwin had written a book and proved\nthis.\"\n\nThe reader will notice that in the report of Mr. Hume's language the\nscholar went somewhat farther than his master had done. Mr. Wilton was\nwell acquainted with the present shape of scientific infidelity, and saw\nthat Ansel's statements were somewhat exaggerated, but he understood in a\nmoment the drift of Ansel's thoughts, though he could not tell as yet how\ndeep and fixed an impression had been made upon his mind. But he did not\ncare to probe Ansel's conscience just then and there, in order to learn\nthe exact state of the case.\n\n\"If I understand you, then,\" he said, \"you would like a course of lessons\nin the teachings of Nature?\"\n\n\"Of course, I did not suppose that you would allow us to have a course of\nlessons in the works of Nature instead of the Bible.\"\n\n\"But if I were willing to give you a course of lessons showing the\nfootprints of the Creator, so to speak, in the physical world, how would\nit please you?\"\n\n\"I should like it very much.\"\n\n\"How would such a plan please the other members of the class?\"\n\nThe idea was entirely new; no one of them had ever dreamed of studying in\na Bible class anything except the Bible; but young people are not averse\nto novelties, and they readily gave their assent. Yet I should do the\nclass injustice by leaving the impression that they were influenced simply\nby the love of something new. They were of just that age when one hardly\nknows whether to call them lads or young men; they had been well\ninstructed, and were just beginning to think independently. They were\nrapidly becoming conscious of their own mental power, and were eager to\ntry their strength upon every line of thought. Their own weakness they had\nhardly begun to learn. Perhaps they were all the more ready to undertake\nsuch a course of study because they knew nothing of the difficulties\nattending it.\n\nThe tinkling of the superintendent's bell warned them to close their\nconversation.\n\n\"We have not time to-day,\" said Mr. Wilton, \"to fix on the particular line\nof study which we shall follow. Of course we cannot examine all the works\nof Nature, and study every science, and trace the footprints of the\nCreator in every place where he has walked; we must fix on some small part\nof the works of God, and direct our attention closely to that. We shall\nfind this course more profitable than roaming carelessly over a much\nlarger space. Our next lesson will have to be a general one--a kind of\npreface to what shall come after. In the mean while, you can be collecting\nyour thoughts upon the subject, and calling to mind anything that you have\nread bearing upon the handiwork of God manifest in Nature.\"\n\nThe school closed, and as the scholars pass out let me introduce to you\nthe members of the pastor's class. This class was small for several\nreasons. The church to which Mr. Wilton preached was not the popular\nchurch. The fashionable people and all who loved popularity and drifted\nwith the tide went to another church. Careless, thoughtless young people\nnaturally went with the crowd, and of those who attended his church some\ndid not care to join his class. He was too much in earnest to please them.\nHe made religion a reality, and his instruction compelled them to think,\nand of course those who did not like to think were not well pleased with\nhim. But there were a few of the young men who were greatly interested in\nhis instructions. They were earnest readers of instructive books; they\nliked conversation which called out thought; they were most of all\npleased with questions and themes which gave them new ideas. Indeed, in\nthe community, there were two classes of persons who held Mr. Wilton in\nthe highest esteem and regard: one of these was composed of men and women\nof earnest, intelligent piety, experienced Christians; the other, of those\nwho were not Christians, but who respected sincerity and disinterested\ngodliness, and liked sermons filled with meat and marrow.\n\nThus, at the present time, we find his class composed of but three young\nmen. With Ansel you are already acquainted. The second is Peter Thornton,\nthe son of a master-carpenter. He was frank, outspoken, quick in the\nacquisition of almost every kind of knowledge, but very little given to\nsilent reflection. He listened to his pastor's instruction as he would go\nto a well-filled library, to draw out its stores of information. Morals\nand moralizing he did not like. He was not pious, and gave no indication\nof serious impressions. The third was Samuel Ledyard, the son of a poor\nwidow. By painful industry and economy his pious mother was giving him the\nbest advantages for education which the village afforded, praying the\nLord to give him a part in the blessed work of preaching the gospel and\nwinning sinners to Christ and salvation. When but twelve years of age he\ngave himself to Christ, and had been trying faithfully to follow his Lord.\nThe long winter evenings were spent in reading books of history and\nscience--books fitted to furnish and strengthen his mind--and long ere the\nlight dimmed the morning star he was poring over his Bible, alternately\nreading the word and praying that his mind might be opened to understand\nthe truth in its beauty and greatness, and that the truth might be wrought\nin him by vital experiences.\n\nWith such habits it was no wonder that he grew in grace--it was no wonder\nthat he grew in all manly qualities. He was silent, meditative, and\nretiring, as gentle in his ways as a quiet girl, yet all who knew him\nrecognized in him a singular weight and worth of character. Those to whom\nthe Lord revealed his secrets began to say that Samuel was appointed of\nGod to preach the gospel, and his mother felt the assurance growing strong\nin her heart that her prayer was granted, and that the Lord was preparing\nher only son and only child for a place in the gospel ministry. If only\nshe might train up a son to such a work, and when she should go to her\nrest leave in her place a man working for Christ in his harvest-field,\ngathering sheaves unto everlasting life, she felt that her cup would be\nfull. She was ready to say with Simeon: \"Now lettest thou thy servant\ndepart in peace, for mine eyes have seen thy salvation.\" How unlike she\nwas to those mothers who lay all hindrances in the way of their sons\nentering the work of the Christian ministry, willing that they should do\nanything but this! and how different from those who declare that their\ndaughters shall never wed ministers of the gospel, teaching them to\ndespise the service of a pastor's wife! How often God gives over such sons\nand daughters--children consecrated from their birth to worldliness--to be\nentangled and lost in worldly snares! As such mothers sow, thus also do\nthey reap.\n\nThese were the three lads, just growing into young manhood, at this time\nunder the instruction of Mr. Wilton. He was not ashamed of his class,\nthough it was small. As he saw them expanding in thought and taking shape\nunder his hand, he felt that in them he was perpetuating his influence in\ncoming generations. He believed that in one or more of them he should\npreach the gospel after his body was sleeping in the earth awaiting the\nresurrection.\n\nI trust the kind reader will be interested in following the course of\nstudy through which their pastor shall lead them.\n\n\n\n\nCHAPTER II.\n\nNEW THOUGHTS FOR THE SCHOLARS.\n\n\nThe little class which has been introduced to the reader came together the\nnext Lord's Day interested and expectant, yet not knowing what to expect.\nThey had chosen a course of study, yet they could not tell what that\ncourse was to be. They had tried to think of something definite about it,\nbut could fix their minds upon nothing. In fact, the whole subject was\nnew, and they could not decide where or how to take hold of it. They came\ntogether, therefore, with no more knowledge of the subject than when they\nseparated.\n\nMr. Wilton himself came before his class in a state of doubt. He had given\nthe subject many hours of thought, and had carried it to his closet and\nbesought the guidance of the Holy Spirit, for he believed the divine\nSpirit to be the best guide in understanding the works as well as the\nword of God. He felt that his prayer had been heard and answered. He was\nprepared, therefore, to speak with the force of clear understanding and\npositive convictions. But the precise line of study he had left to be\ndetermined by circumstances, perhaps by the previous studies of his class\nin their academic course. This was to be decided by further consultation.\n\n\"Since no lesson was assigned upon which you could prepare yourselves,\"\nMr. Wilton said, after the opening exercises of the school were finished,\n\"I shall spend the half hour to-day in a kind of conversational lecture.\nYou may call this the preface or introduction to the lessons which will\nfollow. I shall try to make plain some general principles which we must\nkeep in mind, whatever department of God's works we shall attempt to\nexamine. I wish you to feel entirely free to interrupt me at any time, and\nask any question or present any objection which may strike your minds. We\nmust, if possible, have no prowling bands of enemies in the rear. I wish\nto make everything as plain as the case will admit.\n\n\"One thing let me remind you of in the beginning: I shall not try to prove\nto you that there is a God. I shall not try to prove that the world had a\ncreator. There are some things which men do not believe merely on account\nof good evidence, nor disbelieve for want of proof. Men believe in their\nown existence, but not from a course of argument. Most men believe in the\nreal existence of the outward world--the earth, the hills, the rivers, the\ntrees, everything which we see and hear and feel--but not on account of\nproof. Here and there a strange man is found who professes to disbelieve\nthe real existence of all material things, but he disbelieves not for want\nof proof. Men believe that their sight and hearing and touch do not\ndeceive them, but their confidence in them is not the result of a course\nof reasoning. To believe in our own existence, and in the existence of the\nworld outside of us, and in the truthfulness of our senses, is natural; to\ndisbelieve these things is unnatural: it shows a state of disordered\nmental action. When such disbelief is not practically corrected by a man's\nunderstanding he is counted insane, and is treated accordingly.\n\n\"Belief in the existence of God is also a natural belief. A denial of\nGod's existence shows, not disordered mental action, but a disordered\nmoral and spiritual state. It shows the absence of that spiritual faculty\nby which we receive spiritual impressions, and are brought into contact\nwith the spiritual world, and hold intercourse with God and Christ and the\nHoly Spirit. Men must be convinced of the existence of God through their\nconscience, their moral and spiritual nature. Do not misunderstand me. I\ndo not say that good evidence cannot be brought to prove to one's reason\nthe existence of God, but God has not left his existence to be _proved_:\nhe has _revealed_ himself to men's consciences and to their faith; and\nthose in whom conscience and faith are well developed, sound, and right do\nnot need an elaborate argument to prove the divine existence. I shall\nsimply try to show that the works of creation exhibit the wisdom and\ngoodness of God. If any man, looking at such indications of wisdom and\nkindness, can believe that it all comes by chance or is the work of some\nevil agency, and that no Being of boundless intelligence, wisdom, power,\nand goodness has anything to do with the making and governing the world,\nhe certainly shows great prejudice: he does not want to recognize God's\nexistence. He must be one of those spoken of by the Psalmist who say, 'no\nGod.'\n\n\"During my recent visit to Greenville I visited a mill, the largest of its\nkind in the country. In one room was a machine, something like a huge\nstraw-cutter, working with great power. In another room was a large steam\nboiler hung upon a shaft and made slowly to revolve while filled with\nsteam. In a third room were large oval tanks, or cisterns, which might be\nfilled with water. Across each tank was a heavy shaft carrying a drum set\nwith steel blades, and as the drum revolved these blades passed other\nblades in the bottom of the tank, cutting whatever came between like\nscissors. In a fourth room were certain long and complicated machines.\nEach machine was composed mostly of rollers. There were large rollers and\nsmall rollers, solid rollers of enormous weight, and hollow rollers to be\nheated by steam within. Over and around a portion of these rollers passed\na broad wirecloth belt. Over others passed a like belt of felted cloth.\nWith these machines before you, could you tell me whether the inventor\nwere a wise and skillful machinist?\"\n\n\"How could we tell,\" asked Peter, \"without knowing what kind of work the\nmachine was designed to do?\"\n\n\"You could not tell,\" answered Mr. Wilton; \"you would need to know both\nwhat the machine was designed to do and all the processes by which the\nwork was to be carried on. This brings out the first point which I wish\nyou to fix in mind. It is this: To judge of the wisdom of any contrivance,\nwe must understand the purpose, or object, which the inventor had in view;\nwe must understand the work to be accomplished, and also the difficulties\nto be overcome. An ordinary locomotive steam-engine is admirably fitted to\nrun on iron rails, but he would be a foolish man who should purchase such\nan engine to draw a train of loaded wagons over a common road of earth. On\nsuch a road it could not even move itself. It is good for that for which\nit was made, and for nothing else. How would you apply this principle to\nthe subject we are now considering? You may answer, Samuel.\"\n\n\"I think you mean,\" said Samuel, \"that, in order to judge of the wisdom\nand goodness of God in creating and governing this world, we must know\nthe object he had in view in making such a world.\"\n\n\"That is my meaning, and I am glad that you understand me so perfectly. If\nthis world were created with no other object than to be the grazing-field\nfor herds of cattle, which see no difference between the beauty of the\nviolet and the dull shapelessness of the cold earth upon which it grows,\nand never lift their eyes above the horizon, then all the beauty of earth\nand sky would be useless; there would be no wisdom or goodness in the\ncreation of this beauty. There would be no wisdom or goodness in laying up\nin store beds of coal, buried deep beneath the surface of the earth, if\nGod designed the world to be inhabited only by savages too rude and\nignorant ever to mine it, and turn it to some practical use.\n\n\"But let me give you another illustration, which can better be applied to\nthe condition of things in this world. Just in the outskirts of one of our\ninland cities I once saw a large and elegant building, whether a private\ndwelling or a public institution I could not at first tell. It stood high\nand airy, commanding the most pleasing prospect that all the region\npresented. We will follow a visitor as he goes to examine that noble\nestablishment.\n\n\"As he comes nearer, he sees that the edifice is simple and classic in its\nstyle and chaste in its architectural adornment. It is a pleasure for the\neye to rest upon its graceful symmetry. But in place of the light and\ngraceful fence which he expects to find enclosing its grounds, he sees a\nstockade strong and high. The janitor turns the heavy key, the rusty bolt\nflies back, and the visitor enters the enclosure. Within the stockade he\nfinds a portion of the ground laid out with taste and cultivated with\nchoice and beautiful flowers; another part is devoted to the culture of\ngarden vegetables. He finds workshops also for the manufacture of pails\nand tubs, brooms and mattresses. The visitor is ushered into the mansion\nitself. He finds everything more than comfortable; the rooms are heated\nfrom furnaces below; every part is perfectly ventilated; the windows\ncommand a view of the country around which must please the most cultivated\neye; a school-room is provided with all needed apparatus for the most\nthorough instruction. 'Surely,' says the visitor, 'the founder of this\ninstitution must have been both wise and good. He must have loved the\nyoung in order to study and supply all their needs so completely.' But\nsome things strike the visitor painfully. The windows are grated with\niron, and some of the rooms are almost like prison cells. 'Can it be\npossible,' he thinks within himself, 'that the young need to be confined\nby a stockade in so pleasant a place and shut in by grates of iron for the\nenjoyment of such advantages?' The master as he teaches his pupils seems\nas kind and gentle as a mother, yet there is a firmness and authority in\nhis tones and a rigidity in his training, as if his government were kept\nbraced against a mutinous spirit. The means of punishment also are\nprovided, and, when occasion requires, stern chastisement is employed. All\nthis seems to the visitor like an enigma. The institution appears to him\nlike a bundle of contradictions. A father could not have provided a\npleasanter home or larger advantages for his children, but fathers do not\ncommonly surround their homes with stockades, and cover their windows with\nbars of iron, and train their obedient children with a hand of such firm,\nunyielding force. 'Pray, sir,' he says to the master, 'what is this\nstrange contradictory institution?' 'It is the State Reform School,' the\nmaster answers. 'And who are these lads and young men for whom all this\nwork and wisdom is expended?' 'They are those who have taken the first\nsteps in crime, but have not as yet become hardened and fixed in\nwickedness, and are sent here with the hope of overcoming their vicious\npropensities and training them to virtue and an honorable manhood.'\n\n\"Everything is now made plain. The need of the stockade, and the grated\nwindows, and the rigid government, as well as of the pure air, the\ngarniture of beauty, and the kind loving care, is manifest. It is a place\nunsuited to a family of obedient children, and equally unsuitable as a\nplace of confinement for confirmed criminals, shut up, not for reform, but\nfor punishment. It is wisely adapted to the work designed to be\naccomplished, and to no other.\n\n\"In like manner, if we would judge of the wisdom and goodness of God in\nthe creation and government of this world, we must understand the use for\nwhich the world was designed. Is this plain to you, Ansel, and does it\nseem reasonable?\"\n\n\"Yes, sir; I think I understand it, and I can see no objection to the\nprinciple. I think even Mr. Hume could find no fault with that. But how\nshall we know the object for which God made and governs the world?\"\n\n\"That is the next point to be considered. Perhaps you will tell us what\nseems to you to be that object? Young people sometimes have thoughts and\nopinions upon the greatest questions.\"\n\n\"I have never formed an opinion of my own,\" Ansel replied, \"but I have\nalways heard it said that God designed to show how perfect and good and\nbeautiful a world he could make. But many things in the world seem to me\nneither perfect, nor good, nor beautiful.\"\n\n\"Why, Ansel!\" exclaimed Samuel; \"the Bible says that 'God saw everything\nthat he had made, and behold it was very good.'\"\n\n\"And, Mr. Wilton,\" asked Peter, \"does not the Bible say that 'God created\nall things for his own glory'?\"\n\n\"Before answering any of these questions, let me ask Samuel a question.\nWhat do you understand to be the meaning of the words you quoted from the\nlast verse of the first chapter of Genesis?--'God saw everything that he\nhad made, and behold it was very good.'\"\n\n\"I suppose it means,\" answered Samuel, \"that God made everything just as\ngood and beautiful as it can be, so that any change must be a change for\nthe worse. The lecturer last winter said that if men could entirely\ndestroy any one of the most troublesome species of insects, their\ndestruction would be a great loss to the world, and that if a single atom\nof matter belonging to the earth were annihilated, it might throw the\nsolar system out of balance, so that it would finally be destroyed.\"\n\n\"I remember,\" said Mr. Wilton, \"that some lecturer last winter made\nstatements of that kind, and I have heard other people declare that the\nleast possible change in the world would be injurious, if not destructive,\nto the interests of man, and that the most troublesome beasts and insects\nand the most loathsome reptiles are necessary to human happiness. Does\nthat seem to you to be true, Samuel?\"\n\n\"I have always tried to believe it, because I thought I ought to believe\nit. It has seemed to me to be dishonoring God to believe that he did not\nmake the best possible world.\"\n\n\"You are right in trying to believe what seems to be right and true, even\nthough difficulties do lie in the way. Difficulties do not by any means\nshow that an opinion is false. We must certainly believe that God made\nthis world perfect for the object which he had in view in making it. But\nnot a few skeptics deny the existence of a good, wise, righteous Creator\nand Governor, because they have a wrong idea of the end for which the\nworld was created, and, consequently, a wrong idea of that in which its\nperfection must consist. Let me ask you a few questions which will lead\nyour minds in the right direction. Do not men produce by cultivation\nbetter fruits and vegetables than Nature ever grows when left to herself?\"\n\n\"Yes, sir,\" said Ansel; \"the peach and apple and potato have been brought\nup to their present state of excellence by great care and exertion.\nOriginally, they were almost worthless.\"\n\n\"And not only that,\" said Mr. Wilton, \"but when once that careful culture\nis relaxed they begin to return to their former badness. Again, do we not\nimprove upon Nature by drainage and improve upon the climate by\nirrigation?--in fact, do not men by drainage and irrigation and all\nmanner of culture greatly improve the natural climate of a country?\"\n\n\"I think that is true,\" said Ansel.\n\n\"I never thought of that before,\" said Peter.\n\n\"Moreover, do you not suppose that heaven will be more beautiful than the\nearth, and that a thousand troublesome things besides sin--loathsome\nsights, discordant and jarring noises, disgusting and nauseous odors--will\nbe absent from that 'better land'?\"\n\n\"And _I_ never thought of that before,\" said Samuel. \"I am sure that many\nunpleasant things besides those which sin has brought into the world will\nnot be found in heaven. I see that this world might be changed and not be\nmade worse for holy beings to live in.\"\n\n\"The world is very good,\" said Mr. Wilton, \"for the purpose for which it\nwas created, but we need not look upon it as designed for a specimen of\nthe most beautiful, pleasant, and desirable world which the Creator could\nproduce.\"\n\n\"But you have not told us,\" said Peter, \"what the Bible means when it says\nthat God created all things for his own glory. Does it not mean that he\nmade the world so good and perfect that all creatures ought to praise him\non account of it?\"\n\n\"We ought,\" said Mr. Wilton, \"to praise God for the wisdom and goodness\ndisplayed in the works of creation. That is the teaching of the Bible in\nmany places; it is also the sentiment of the Bible that God created the\nworld and carries on all things for his own glory, but it nowhere uses the\nexact language which you have employed. In Isa. xliii. 7, speaking of\n'every one that is called by my name,' the Lord says, 'I have created him\nfor my glory.' In Prov. xvi. 4 it is written, 'The Lord hath made all\nthings for himself; yea, even the wicked for the day of evil;' and the\nfour and twenty elders fell before the throne of God saying: 'Thou art\nworthy, O Lord, to receive glory and honor and power; for thou hast\ncreated all things, and for thy pleasure they are'--that is, exist--'and\nwere created.' I might quote other texts of similar meaning. We are taught\nalso that our first and supreme aim in all our conduct should be the glory\nof God. 'Whatever ye do, do it all to the glory of God.' But here two\nquestions arise: What is the glory of God? and, What is it for God to\nglorify himself by his works of creation and government? Who will tell\nus?\"\n\nAll were silent, and Mr. Wilton went on speaking: \"The word glory means,\nfirst and literally, a halo of light. The glory of God is the radiance, or\nhalo, so to speak, of his infinite attributes and holy character. God\nglorifies himself when he reveals himself, and makes known his character,\nand causes the uncreated splendor of his attributes to break forth, so\nthat his creatures recognize them and adore him. This, you see, is very\ndifferent from the idea of glory among ambitious men. God glorified\nhimself in the creation of the physical world, because from that creation\nhis wisdom, power, and goodness are manifest. He glorified himself in the\ncreation of angels and men, because they were created in the image of God\nand are finite pictures, so to speak, of the infinite Creator--a\nrevelation of his spiritual being and personality. He glorifies himself in\nhis government of the world, because his administration of affairs\nexhibits his justice, mercy, and holiness. This is what we mean by the\nglory of God and his working all things for his own glory. This is\nsomewhat difficult for persons of your age, so we will leave it and\nreturn to the exact subject of discussion. Admitting that God created the\nworld and governs it for his own glory--that is, to reveal himself--for\nwhat specific purpose did he design this earth?\"\n\n\"I don't know,\" said Peter, \"that we understand what you mean by 'specific\npurpose.'\"\n\n\"Very well, then,\" said Mr. Wilton; \"I will suggest the answer. Does the\nworld seem as if fitted up to be the dwelling-place of holy beings?\"\n\n\"I have never thought of the question before,\" said Ansel; \"but it seems\nto me that many things in this world would give pain even to angels if\nthey lived here with bodies like ours.\"\n\n\"I agree with you, Ansel. If men were sinless and holy as the angels of\nheaven, many things in this world would bring them distress. But does it\nseem reasonable that the world was designed merely as a place of\npunishment for men by reason of their wickedness?\"\n\n\"Some men are not wicked,\" replied Samuel. \"There have always been men\nwilling to die rather than disobey God. Surely, God does not punish such\nmen. And many beautiful and pleasant things are found in the\nworld--arrangements plainly designed for the welfare and happiness of\nmen.\"\n\n\"I think you are right, Samuel. But, without asking further questions, I\nwill give you the conclusions to which my study upon this subject has\nbrought me, and some of the reasons for those conclusions.\n\n\"This world was made chiefly as the dwelling-place of man. The world was\nnot planned merely as the abode of brute animals. Men are nobler than the\nbrutes. Men have permanent interests and advantages. Aside from the glory\nof God, men are an end unto themselves. To become and be _men_ is the\nnoblest object of human life, but the animal tribes exist for the use and\nbenefit of others. To be an end to itself, a creature must be immortal;\nbut the brutes exist for the use and advantage of man, live out their\ntransient life, and exist no more. This is the view presented in the\nsacred Scriptures. God gave to man lordship over the earth--not only over\nthe soil to subdue it, and over the great forces of Nature to bring them\ninto subjection for human advantage, but also over the brute creation,\n'over the fish of the sea, the fowls of the air, and every living thing\nthat moveth upon the earth.' I conclude also that God did not prepare this\nworld as a prison-house and place of punishment for rebels against his\ngovernment. Too many pleasant things abound for me to believe that. The\npleasant breezy air, the glorious sunlight, the refreshing showers, the\ntreasures of mineral wealth stored up in the earth, the fertile land and\ngolden wheat, the beauty spread over all nature, the sweet consciousness\nof existence, so that just to live and act is joy, and the comfort and\nhope of immortal pleasure enjoyed by truly Christian men,--all these\nthings, and many more, assure me that not the subtle shrewdness of a\ntormentor nor the unmingled justice of an inexorable judge, but the heart\nof a kind and loving Father, planned our earthly dwelling-place. You said,\nSamuel, with truth, that there are many pious men in the world who are\ndear to God, and Paul says, 'We know that all things work together for\ngood to them that love God.' For those dear ones Christ has such love that\nhe counts everything--whether good or bad--that is done to them as if done\nto himself. 'Inasmuch,' he says, 'as ye have done it unto one of the least\nof these my brethren, ye have done it unto me.' Moreover, Jesus said:\n'For God so loved the world, that he sent his only begotten Son, that\nwhosoever believeth in him should not perish, but have everlasting life.'\nFrom these words of Jesus we see that there is love manifested in the\ndealings of God with the inhabitants of our world. Were it not so, there\nwould nothing remain but a 'fearful looking-for of judgment and fiery\nindignation, which shall devour the adversaries.'\n\n\"On the other hand, I conclude that God made the world as the\ndwelling-place, not of obedient, holy children, but of those who are\ndisobedient, fallen, and alienated. These disobedient and alienated ones\nhe holds under discipline and chastisement, in order to keep their\nwickedness in check, to recover them from their sins, and train them up in\nvirtue and holiness, or to remove from the obstinate and incorrigible all\nexcuse for their sins and all plea against their final condemnation. In\ndoing this he glorifies himself by manifesting his wisdom, goodness,\nmercy, and holiness.\n\n\"This opinion seems probable from the fact that this is the purpose for\nwhich God has actually used and is now using the world. Here he keeps and\ngoverns the human race. This race is made up neither of holy beings nor of\nhopeless reprobates. They are the creatures of God; fallen indeed, yet\nloved; sinful, but objects of divine compassion; deserving of righteous\nwrath, but the recipients of the offers of salvation through Christ. Even\npenitent believers in Christ and devoted servants of God are not free from\nevil propensities, but need to be kept under constant training and\ndiscipline. This is the use to which the Creator has actually put the\nworld. Is it not reasonable to believe that he designed it for their use?\nOught we to believe that God planned the world for an object for which it\nnever has been and never will be employed?\n\n\"If sin were removed from the world, the chief part of human suffering\nwould be removed. This no man can deny. Wars would cease; the want,\ndisease, and woe resulting from selfishness, idleness, and vice would\ndisappear, and nothing would stand between man and his Maker. What new\nlife and joy would fill the world if free communication were restored\nbetween man and God, and the divine smile were again to enlighten the\nworld! It would seem that heaven had enlarged her borders to embrace this\nearthly ball. But the fact would still remain that this physical world is\nunfitted to be the dwelling-place of sinless beings. The constitution of\nthe world would bring upon them pains and evils which would seem a most\nunworthy heritage for loving and obedient children of our heavenly Father.\nLet sin be taken away, and wearisome toil in subduing the earth would\nremain. The soil of the earth is hard and clogged with stones, and clammy\nwith stagnant waters, and sown well with the seeds of noxious weeds, and\novergrown with thorns and thistles. Endless watchfulness and toil is the\nprice of a livelihood. With the sweat of his face man must eat his bread.\nAn army of enemies have pre-empted the soil which man must till. This\nstate of things the word of God refers to sin: 'Cursed is the ground for\nthy sake; in sorrow shalt thou eat of it all the days of thy life. Thorns\nalso and thistles shall it bring forth to thee.' The necessity of toiling\nas we do now for our daily bread, God denounced upon man as a curse on\naccount of sin. We cannot, therefore, regard this as a suitable condition\nfor sinless beings.\n\n\"This burden of toil is lightened by the progress of modern sciences and\ninventions much less than some men think. Every step of progress has been\nmade by the sacrifice of hecatombs of human lives. From our laboratories\nand workshops products of human skill, rich and rare, are sent forth; but\nwhat are they but smelted and hammered and graven and woven human bones\nand sinews, the health and life of men? No means have been discovered by\nwhich the most necessary processes of the arts can be made otherwise than\ndangerous to health. Only when thousands of miserable workmen had perished\nwas Sir Humphrey Davy's safety-lamp invented; and now the danger, to say\nnothing of the hard toil, of the collier's life is only lessened, but not\nremoved. Still, our furnaces roar and the whole tide of civilization goes\non by the health-destroying servitude of men, buried alive as it were in\nthe dark bosom of the earth. Would that seem to be a fitting employment\nfor the sinless children of the all-loving Father? Employes in many kinds\nof manufacture slowly sink under the accumulated evils of daily toil, and\nno means of making their employments healthful have been discovered. The\nfriction-match, which has become so nearly a necessity, is made by a\nprocess so destructive to health that only a certain class of laborers can\nbe prevailed upon to do the work. I might go on to speak of other painful\ncircumstances in which men find themselves by the almost antagonistic\nattitude of Nature. But if we reject these dangerous processes of\nmanufacture and art, we go back at once to the wooden plough, the distaff\nand tinder-box of primitive times, and also to primitive poverty and\nprimitive toil, and, I may also add, to primitive exposure to the hostile\nand pitiless forces and inclemencies of Nature. Purge the earth of sin,\nand wearisome toil would still remain. Nature must be nursed and\ncultivated or she yields no bread. Her hostile attitude must be overcome;\nthe thorns and thistles must be rooted out; and every step of progress,\nwon by suffering, must be held by painful work and watchfulness; otherwise\nNature returns to the wild and savage state. Relax the culture of the\nchoicest fruit, and it begins to deteriorate; leave the best-blooded breed\nof cattle to itself, and it returns again to the level of native,\nuncultured stock.\n\n\"The inhabitants of this world are also liable at all times to diseases\nand destructive accidents. This condition of things could not be changed\nwithout changing the entire structure and plan of the world. Is that a fit\ndwelling-place for a sinless being where chilling winds one day shrivel\nhis skin and fill his bones with rheumatic pains, and the next, sweltering\nheats pervade all his system with languid lassitude--where miasma lies in\nwait unseen to poison his blood, kindle the malignant fever, and bring him\nto the shades of death, and every form of accident crouches in ambush,\nready to spring upon his victim unawares and tear him limb from limb? We\ncannot see that the absence of sin would dissipate this liability to\ndisease and the danger of accidents. Nay, this liability and danger are\nwritten upon the very constitution of the human body. The finger of God\nhas engraved it upon every muscle and bone and life-cell. The Creator gave\nthe body that wonderful power called the _vis medicatrix_--the power of\nrecovering from injuries and repairing damage done to itself. Pull a leg\nfrom a grasshopper and another grows in its place. By this we know that\nthe Creator understood the liability of this little insect to lose a limb,\nand prepared him for it. In like manner the power in man's body to heal a\nwound or join a broken bone gives us to understand that the Creator\nexpected man to live in the midst of danger. The precaution proves the\nrisk.\n\n\"These accidents are such as no possible carefulness could guard against.\nTo say nothing of the fact that all our knowledge of these perils comes\nfrom a painful experience of danger and death, what care, even after ages\nof sad experience, could ward off the thunderbolt? What carefulness could\nguard against the tornado on the land, or the hurricane and the cyclone\nupon the sea? Who should stand sentinel against the unseen poison borne\nupon the wings of the wind? What power should save him from the bursting\nof the volcano and the jaws of the earthquake? What care could give him\nknowledge of the qualities of all natural substances, that he might avoid\ntheir dangerous properties? We can suppose a divine care over man that\nshould do all this and save men from harm, but it would be a providence\nsuperseding all human knowledge and exertion--it must be a providence to\nwhich the human race is now a stranger; miracles would then be the rule,\nand the undisturbed course of Nature the exception.\n\n\"If, however, we suppose that God designed the world as a training-school,\nso to speak, of fallen beings, such as the word of God declares the human\nrace to be, all is plain, everything is suitable and harmonious. We can\nsee the fitness of at least the chief outlines of man's earthly condition,\nand can perceive God's wisdom and goodness in the constitution of the\nworld.\n\n\"The pain and woe-producing agencies of Nature are seen to be not at all\ncontradictory to goodness, but on the other hand eminently wise and\nrighteous. The whole sum of human misery expresses God's displeasure at\nsin. By their sufferings men learn how abhorrent is sin in God's sight. By\nthe consequences of evil-doing they learn not to transgress. As none are\nfree from the taint of depravity, none are free from pains. The necessity\nof labor--one of the elements of the primal curse--is a check to sin on\nthe part of the vicious, and a discipline and trial to virtue on the part\nof the penitent. The multiform trials of life--which can indeed be borne\nwell only by the grace of God--while they teach the evil of sin and keep\nthe heart chastened and subdued, nourish heroic and dauntless virtue in\nthe faithful. 'Daily cares' become 'a heavenly discipline.' Dangers and\ncalamities startle the stupid conscience, and keep alive the sense of\nresponsibility to God on the part of the wicked; they quicken the sense of\nweakness and dependence in the believing and educate their faith in God.\nThe more sudden and overwhelming these evils, and the more these dangers\nare placed beyond the possibility of being warded off by human care, the\nmore do they awaken in men a sense of the divine presence and of\nresponsibility to God.\n\n\"But would not all these natural agencies subserve essentially the same\nends in the discipline of unfallen and sinless beings? By no means. If\nsufferings came upon a sinless being, he could not feel that they came as\nchastisements; he could not feel them to be deserved. They would be to him\na 'curse causeless,' and hence would bring no advantage. He could only cry\nout in astonishment, 'Father, why am I, thine obedient son, thus smitten?'\nCalamity falling upon the innocent would be an anomaly in the universe.\nBut now the sufferer, pierced through and through with a sense of ill\ndesert, meekly bows his head, murmuring, 'Father, all thy judgments are\njust and right.'\n\n\"One very important feature of the world we live in is its moral\nsymbolism. The world is full of most suggestive symbols and emblems of\nmoral good and evil. There are all beautiful and glorious things, to stand\nas types of goodness, truth, and righteousness; there are all loathsome,\nmalignant, and hideous things, to serve as the types of folly and\nwickedness. Was it merely an accident that the dove was fitted to become\nthe emblem of purity and of the Holy Spirit? the lamb, to be the emblem of\ngentleness, of Christ the gentle Sufferer, and of his suffering people?\nthe ant, to be the type of prudent industry? the horse, of spirit and\ndaring? and the lion, of strength and regal state? Was it only an accident\nthat prepared cruel beasts and disgusting, poisonous reptiles as the types\nof evil passions and sins--that made the venom of the viper, the cunning\nof the fox, the blood-thirstiness of the wolf, the folly of the ape, and\nthe filth of the swine, symbols of foul, subtle, malignant sin and folly?\nNature is full of these emblems. The palm tree with its crown of glory,\nthe cedar of Lebanon, the fading flower and withering grass, the early dew\nand the morning mist, the thorn hidden among the leaves of the fragrant\nrose, poisons sweet to the taste, and medicines bitter as gall,--how all\nthese natural things preach to men sermons concerning spiritual verities!\nThere is no virtue or grace which is not commended to man by its image of\nbeauty in the animal tribes; there is no vice against which men are not\nwarned by its loathsome, disgusting form shadowed out in the instinctive\nbaseness of irresponsible brutes.\n\n\"Thus we find earth, air, and sky to be full of silent voices proclaiming\nin the ears of man that which he most of all needs to remember. These\ntypes and symbols of virtue and vice are specially needed by fallen\nbeings. They seem fitted for beings whose spiritual eyes are blinded and\nall their spiritual senses blunted--beings with whom there is no longer\n'open vision' of spiritual realities. These pictures of evil are most\nimpressive to men who see in them the reflection of their own base\npassions. How the fetid goat and the swine wallowing in the mire speak to\nthe lecherous man and the drunkard! In a world of sinless beings these\nmimic vices would seem rather to mar God's handiwork.\n\n\"Set the human race, fallen as it is, in a world where the patience of\ndaily industrious toil would not be needed, and the race would rot with\nputrid, festering vice. Remove all danger, and men would forget and deny\nthat the Creator holds them responsible. Let no evil consequences follow\nevil-doing, and men would cease to make a distinction between right and\nwrong. Take away death, and they would deny the existence of a spiritual\nworld. But in this world God has hedged men around with checks and\npenalties and painful discipline, such as are of use only in dealing with\nsinners.\n\n\"I conclude, therefore, that God prepared this world as it now is as a\nplace of discipline for a fallen race. This is the use to which he has\ndevoted it in the past; and when there is no longer need of such a world\nfor the discipline of men, we learn from the word of God that a 'new\nheaven and a new earth' shall be provided. This world is thus declared to\nbe an unfit abode for the glorified saints. To judge, then, of the wisdom\nand goodness of God in the works of nature, we must keep in mind the\nobject for which the Creator prepared the world. Ansel, tell us how this\nstrikes you.\"\n\n\"I never thought of it in this way before,\" he answered; \"indeed I have\nthought very little of this subject, but--\" Tinkle, tinkle went the bell\nupon the superintendent's desk. This was the second time the\nsuperintendent had struck his bell, but Mr. Wilton had been so intent upon\nhis subject that he did not hear the first ringing.\n\nThe school was dismissed, but Mr. Wilton remained with his class to fix\nupon the particular department of nature which they would study. He found\nthat all were studying natural philosophy, and had recently gone over the\nsubject of heat. At his recommendation, therefore, they agreed to examine,\nas a specimen of God's works, his management of heat in the world. Mr.\nWilton requested them to review the subject during the week, and be\nprepared to state and apply the general principles touching the nature,\nphenomena, and laws of heat which they had already learned. This work they\nwill enter upon next Lord's Day.\n\n\n\n\nCHAPTER III.\n\nA DIFFICULT QUESTION.\n\n\nDuring the week, Ansel, Peter, and Samuel were busy reviewing and fixing\nin memory what they had already learned of the nature and laws of heat.\nThey were not only interested in the new line of study, and desirous of\npleasing Mr. Wilton, but they also felt that their scholarship was to be\ntested, and each one was ambitious of standing equal to the best.\n\nAnsel, of course, was busy and ambitious. The lesson was coming somewhat\nupon his own ground, and he felt in no wise unwilling to show how well he\nhad mastered the subject. He entered upon it with feelings a little\ndifferent, however, from his anticipations. The explanation which Mr.\nWilton had given of the purpose of the Creator in making such a world\nseemed to him very reasonable. He could make no objection to it. But that\nexplanation had taken away at one sweep a whole store of objections to\nGod's goodness which he was waiting to bring out as soon as a good\nopportunity was presented. A world designed for the dwelling-place of\nsinners--sinners not already given over and doomed to final wrath, but to\nbe recovered from sin and trained in virtue and holiness, or, if\nincorrigible, to be held in check and used as helps in the discipline of\nthe righteous--he plainly saw must be as unlike a world fitted up for holy\nbeings as a reform school is different from a home for kind and obedient\nchildren. Those arrangements which he had thought the most painful and\nobjectionable might, after all, be the wisest and best. He did not see\nwhere to put in a reasonable objection to Mr. Wilton's unexpected\nargument, yet he did not feel quite satisfied to confess to himself that\nhe was so soon and so easily defeated.\n\nIn this state of mind, on Saturday morning he met Mr. Hume upon the\nstreet.\n\n\"Good-morning, Ansel,\" said Mr. Hume.\n\n\"Good-morning,\" returned Ansel.\n\n\"I hear,\" said Mr. Hume, \"that you have given up studying the Bible in\nyour Bible class, and have begun the study of natural philosophy. Is that\nso?\"\n\n\"Not quite true, Mr. Hume. We are to examine some department of the works\nof Nature, and see what indications appear of the Creator's wisdom and\ngoodness.\"\n\n\"That is a little different from the report which came to me. But what did\nyou learn last Sunday?\"\n\n\"Mr. Wilton told us that in order to judge of the wisdom and goodness of\nGod in any of the affairs of this world we must consider the object for\nwhich that arrangement was designed. He said that if a man examine a\ncotton-gin, supposing it to be a threshing-machine, he would be likely to\npronounce it a foolish and worthless contrivance; and that the fine edge\nof a razor would be worse than useless upon the cutter of a breaking-up\nplough. He told us that the earth was not prepared as the dwelling-place\nof sinless beings, but as a place of discipline for the fallen human race,\nand that we ought not to look upon it as the choicest specimen of\nworkmanship which the Creator could construct.\"\n\n\"I have heard that Mr. Wilton believes something of that kind. Ansel,\nhave you studied geology?\"\n\n\"I have read a little upon that subject and have heard some lectures.\"\n\n\"Can you tell me, then, whether or not the natural laws which prevailed on\nthe earth ages and ages ago, before the earth was fit for men to live upon\nit, are the same as those which have been in operation in these later\nages, since men have inhabited it?\"\n\n\"I suppose that the same laws have prevailed from the beginning of the\ngeologic periods. I think that geology makes that very evident.\"\n\n\"If that were not so,\" said Mr. Hume, \"the past history of the globe would\nbe a riddle to us; it would be confusion worse confounded. In regard to\nthose early ages we could not reason from cause to effect, for we should\nknow nothing of the forces and principles then in existence. In geologic\nstudies we judge the past from the present, and if that be not a\ntrustworthy method of reasoning, all the conclusions of geologists are as\nworthless as dreams. Have you any reason to suppose, from what you have\nread on this subject, that a curse changed the character of the earth as a\ndwelling-place for man some six thousand years ago? Is it true, as Milton\nsays, that then\n\n                                          'The sun\n    Had _first_ his precept so to move, so shine,\n    As might affect the earth with cold and heat\n    Scarce tolerable, and from the north call\n    Decrepit winter--from the south to bring\n    Solstitial summer's heat'?\n\nDid the Creator then\n\n                      'Bid his angels turn askance\n    The poles of earth twice ten degrees and more\n    From the sun's axle'?\n\nOr was death then first introduced among the brute creation, as Milton\nfancies?--\n\n                      'But Discord first,\n    Daughter of sin, among the irrational\n    Death introduced through fierce antipathy;\n    Beast now with beast 'gan war, and fowl with fowl,\n    And fish with fish; to graze the herb all leaving,\n    Devoured each other.'\"\n\n\"Animals must have died,\" said Ansel, \"for their remains lie imbedded in\nrock which certainly existed before man lived on the earth.\"\n\n\"I wish you would ask Mr. Wilton one question for me.\"\n\n\"I am willing to ask him any proper question, and I suppose you would not\nwish me to ask any other.\"\n\n\"I certainly would not. Will you ask him how it was possible for man not\nto sin and fall if God created the world for a sinful race myriads of ages\nbefore man was brought into existence? It would seem that if man had\nremained obedient he could not have lived pleasantly in a world prepared\nfor sinners, and at the same time, by man's obedience, all the Creator's\nplans touching this world would have been dislocated and disappointed.\"\n\n\"I will ask him, sir,\" said Ansel, \"at the first good opportunity.\"\n\nThis good opportunity occurred sooner than Ansel expected, for, before\nentering upon the proposed lesson the next Lord's Day, Mr. Wilton said to\nthe class:\n\n\"I wish in these lessons to advance carefully and safely, and, as far as\npossible, have everything well understood. For that reason I invite you to\nspeak freely of any difficulties or objections which may suggest\nthemselves to your own minds or which you may hear presented by others. At\nthe close of the last lesson the views which I had presented to you seemed\nvery reasonable, but it is possible that, as you have thought upon the\nsubject during the week, objections may have arisen in your minds. If so,\nI should be glad to hear them now.\"\n\n\"There are many things,\" said Peter, \"of which I cannot see the use, even\nif we suppose that the earth was designed as the dwelling-place of\nsinners.\"\n\n\"It would be very surprising indeed if you could unravel all the mysteries\nof creation in a week's time. Wiser men than any of us have spent a\nlifetime in searching out the meaning of God's works, and died still in\nthe dark upon many points. We need not expect to unravel and understand\nall the deep, complex, and delicately-interwoven contrivances in a world\nso vast and curious as this. The world is a great mystery--mysterious as a\nwhole, and mysterious in all its parts--upon any supposition. But the\nexplanation which I gave of its design furnishes a sufficient reason for\nthe great outline of creation. This gives a reason for the pains and\nmiseries which dog man at every step. This gives a reason for the earth's\nbeing left rugged and sluggish, bringing forth thorns and thistles, and\nrequiring to be subdued by patient industry. It shows a ground for the\nnecessity of exhausting toil under a frowning sky and mid miasmatic\nairs--for the liability to diseases and accidents, and the hard necessity\nof death. These great elements of divine providence are not stripped of\ntheir halo of mystery, but with this explanation they are seen to form a\nharmonious whole for the accomplishment of a great and glorious purpose.\"\n\nMr. Wilton paused. Then Ansel said, \"Mr. Hume wished me to ask you a\nquestion.\"\n\n\"Very well, I should be glad to hear it. I hope, indeed, that he sends his\nquestion from interest in the subject, and not with the design of\nperplexing us. I wish also that he were here to ask the question and hear\nthe answer for himself. But what is the question?\"\n\n\"He wished me to ask how it was possible for man not to sin and fall if\nGod placed him in a world prepared for a race of sinners and unfitted for\na sinless race. He said that in such a case, if man had remained obedient,\nthe plans of God would have been disarranged.\"\n\n\"What answer did you try to give him, Ansel?\"\n\n\"I did not try to make any explanation. It seemed to me a very great\nobjection. I did not see how such a course was consistent with God's\nrighteousness.\"\n\n\"And you are not the first person who has objected to this as a great\ninconsistency. I am afraid the discussion will take more time than we\nought to spare, but now that the question has been asked and the objection\npresented, I must take time to answer it, even if it consume the whole\nhalf hour.\n\n\"In considering this subject, as well as many others, we need to remember\nthat the existence of difficulties is no objection to a principle or a\nfact. Difficulties wholly inexplicable by man attend facts and principles\nwhich must be true. A fact may be incomprehensible, though undeniable. The\ngreat Doctor Johnson said, 'There are insuperable objections against a\nplenum, and insuperable objections against a vacuum, yet one of these must\nbe true.' What did he mean by that, Samuel?\"\n\n\"He meant, I suppose, that we could not explain the possibility that any\nspace should be wholly empty of matter, and could no more explain the\npossibility that any space should be filled with matter, but that all\nspace must be filled, or else there must be empty space. Whether we can\nexplain the possibility or not, one of them must be true.\"\n\n\"That is right. The same is true of many other facts besides a plenum and\na vacuum. We cannot conceive of infinite space; we cannot conceive that\nspace should not be infinite, but bounded. We cannot conceive of the\ncreation of the world from nothing, and no more can we conceive of its\neternal existence. The truth is that the mind of man cannot grasp such\nsubjects so as to reason upon them correctly. No sooner do we attempt to\nreason about the infinite things of God than we run into absurdities and\nreach the most contradictory conclusions. And in this respect it makes no\ndifference with what principle or proposition we start if it only contain\nsome infinite element. Let me give you a simple illustration from\ngeometry--an illustration which, very likely, is familiar to you: the\nlarger a circle, the less is the curvature of the line which bounds it;\nthat is, the more nearly does that line approach a straight line. An\ninfinite circle must be bounded by a straight line, because with any\ndegree of curvature the circle would be less than infinite. But a\nstraight line cannot bound a circle. The attempt to reason about an\ninfinite circle brings us at once to the most palpable absurdities and\ncontradictions. Or take this illustration: the whole of a thing is greater\nthan any of its parts. But divide a line of infinite length in the middle,\nand each part is infinite. We reach the conclusion either that the half is\nequal to the whole or that other wholly incomprehensible proposition, that\none infinity is twice as great as another infinity. I have made these\nstatements to show you that the existence of difficulties does not\nindicate, much less prove, that a fact is not real and true.\n\n\"Mr. Hume thinks the fact that the earth existed in its present condition\nbefore men sinned an insuperable objection to the view that this world was\nprepared as a place for the discipline of a fallen race. But let us look\nat the other side, and see if equal objections do not exist. The Creator\nforesaw the fall of man; is there no objection to the supposition that,\nknowing that man would sin, God made no provision for it? On the one\nsupposition he foresees the evil and makes no provision; on the other, he\nforesees it and provides for the catastrophe. The former supposition\ncertainly involves the greater difficulties.\n\n\"The objector may reply that the plan of God, by embracing the fall of man\nand including it as one of its essential elements, made that fall\nnecessary. But why should not God embrace in his plan that great event,\nthe fall of man, which he foresaw in the future? Would it have been wiser\nand better to leave out of account that most stupendous fact in the\nhistory of the human race? This same objection, which Mr. Hume and many\nothers have brought forward, lies with equal force against the great\ncentral fact of the gospel, the death of Christ. God's plan touching this\nworld included the incarnation and death of his Son. Jesus, the 'Lamb of\nGod,' is spoken of as 'slain from the foundation of the world.' Rev. xiii.\n8. But the incarnation and death of Christ presuppose the apostasy of the\nhuman race. Did this plan touching Christ make the apostasy of man a\nnecessity? If preparing a world--fallen, so to speak, beforehand--for a\nrace which God foresaw would fall, be inconsistent with his righteousness,\nit must be equally inconsistent to prepare a Saviour beforehand for that\nsame race.\n\n\"Again, the divine plan touching the death of his Son included his\nbetrayal by Judas and his crucifixion by the Jews. If Judas had known that\nGod had poised the salvation of man upon the pivot of his treachery, he\nwould doubtless have argued as Mr. Hume and others are accustomed to do.\nBut did God's plan excuse his treason against his Lord? His own\nconscience, piercing and rending his soul with remorse, drove him to\nself-destruction, and Christ confirmed the sentence of his conscience and\ncalled him the 'son of perdition.' The fact that God weaves the foreseen\ncrimes of men into his plans is no palliation of their guilt.\n\n\"Would it be wise and well to take no account of foreseen events? Jesus\nhas gone to prepare mansions for those who will, as he foresees, believe\nin him: why not make provision for foreseen evils also? Our civil\ngovernment, knowing the liability to crime among men--a liability which\nthe experience of man has shown to be a practical certainty--makes\nprovision for those crimes by maintaining a police, reform schools,\nprisons, and armies. The Governor of the universe, knowing the liability\nof man to sin and fall--a liability which by his foreknowledge was to him\na certainty--made provision for that foreseen apostasy. He made provision,\nboth by the creation of a world suited to a sinful race kept under a\nprobation of mercy, and by appointing a Redeemer, the 'Lamb of God,'\nslain, in the eternal purpose, before the foundation of the world. If Mr.\nHume's objection has force at all, it has force against every wise\nprovision of God to meet the consequences of man's foreseen wickedness. It\nis wise, forsooth, on man's part, to foresee coming evil and prepare for\nit; but if God do this, men count it worse than folly: they declare it to\nbe an endorsement of the evil! So foolishly do men reason about the high\nthings of God! My answer to Mr. Hume, then, has four parts:\n\n\"1. The existence of unexplainable difficulties does not disprove the\ntruth and reality of any fact or principle.\n\n\"2. The supposition that God made provision for the present apostasy of\nthe human race is burdened with fewer and smaller difficulties than its\ndenial.\n\n\"3. The word of God declares that he did make provision for the fall of\nman by the pre-appointment of a Redeemer.\n\n\"4. That style of reasoning which seeks to justify or palliate man's first\nsin because God prepared this world for a fallen race would palliate and\njustify all wickedness, because the sins of men are woven into every\nfigure of the web of divine providence. Not the treason of Judas alone,\nbut the whole sum of man's evil-doing, is embraced in the far-reaching\nplan of God. How this magnifies the wisdom of God! He binds together in\none bundle his own righteousness and the sins of men, in a most intricate\ninterlacing, yet without blending the two and without staining the glory\nof his holiness.\n\n\"I hope I have made this plain. Do you think, Ansel, that you can repeat\nthe substance of this answer to Mr. Hume?\"\n\n\"I will try, sir, if he asks.\"\n\n\"You will all notice,\" added Mr. Wilton, \"that I have not denied that\nthere is a deep mystery in this preparation for the sins of men not yet\ncreated, and that I have not attempted to explain this mystery. I have\nonly tried to show that the admission of the view I have given you is more\nsatisfactory to reason than its denial, and that the mysteries of this\nview are not unreasonable and self-contradictory, for the greatest\nmysteries are often the most reasonable things in the world.\n\n\"My introduction has become much longer than I designed, but now let us\nturn our attention to the subject of the lesson.\n\n\"To aid us in understanding God's wise arrangements in the management of\nheat, we need, first, to consider what heat is and to review the laws of\nits action. Without this, we could look on and wonder at God's working in\nnature, but could not explain that which we saw.\n\n\"Ansel, will you state the theories which have been held touching the\nnature of heat?\"\n\n\"I will do it as well as I can. The ancient philosophers supposed fire to\nbe one of the four elements of which all bodies were composed. The three\nother elements were earth, air, and water. These four elements were\nmingled in various proportions. Of these, fire was esteemed the purest and\nmost ethereal; this constantly tended upward to the empyrean, the highest\nheaven, where the element of fire and light was supposed to exist\nunmingled and pure. In the seventeenth century, Beccher and Stahl, two\nGerman chemists, brought forward what is known as the _phlogistic\nhypothesis_. They supposed that every combustible body held in\ncomposition a pure, ethereal substance which they called _phlogiston_, a\nGreek word which signifies _burned_, and that in combustion this\nphlogiston escaped. Flame was supposed to be this escaping phlogiston.\nThese were the notions held about fire and combustion, but they are hardly\nworthy to be called theories of heat. The discovery of oxygen by Dr.\nPriestley of England, in 1774, and the introduction of the balance by\nLavoisier of France, joined with the ever-enlarging circle of facts to be\nexplained, rendered the phlogistic hypothesis untenable, and it was thrown\naside.\n\n\"Until a few years since the _caloric_ theory was generally received.\nAccording to this theory, heat is a _substance_, a subtle ether, diffused\nthrough all bodies and surrounding their atoms. This ether has been\nsupposed to have a strong attraction for the atoms of every other\nsubstance, while between its own atoms a strong repulsion exists. In solid\nbodies each atom of matter, or in compound bodies each cluster of atoms,\nhas been supposed to be surrounded by a little atmosphere, so to speak, of\ncaloric, which prevented the atoms from coming into absolute contact.\nAccording to this theory, heat expands bodies by increasing and deepening\nthese minute atmospheres, thus pressing the atoms farther from each\nother.\"\n\n\"You need not explain this theory farther,\" said Mr. Wilton; \"we have\nhardly time to go into the history of theories. Tell us the latest\nreceived theory.\"\n\n\"The theory now commonly believed is called the _mechanical_ or _dynamic_\ntheory. According to this theory, the essence of heat is _motion_. A hot\nbody is one whose atoms are in a state of rapid and intense motion or\nvibration; and the sensation of heat on touching a hot body arises from\nthe impact, or rapid blows, of the agitated atoms, communicating the same\natomic vibration to the flesh and nerves of the hand.\"\n\n\"Very well stated, Ansel. This is the theory now more commonly received.\nThe caloric theory, like the crude notions of the old Greek philosophers\nabout fire, and like the phlogistic hypothesis, has been rejected because\nit failed to explain the phenomena of heat. Whether the dynamic theory is\ndestined to share the same fate remains to be seen. It seems, however, to\nhave a better foundation than its predecessors. The dynamic theory,\nthough recently made popular, is by no means a recent conception. It was\nadvocated by such men as Bacon, Newton, Rumford, Davy, Locke, and others.\nLocke, the distinguished intellectual philosopher who lived in the latter\nhalf of the seventeenth century (born 1632, died 1704), said, 'Heat is a\nvery brisk agitation of the insensible parts of an object, which produces\nin us that sensation from which we denominate the object hot, so that what\nin our sensations is heat in the object is nothing but motion.' Benjamin\nThompson, an American gentleman who went to Europe in the time of our\nrevolution, and for his scientific fame was made Count Rumford, and became\nthe founder of the Royal Institution of England, declared that he could\nform no conception of the nature of heat generated by friction unless it\nwere motion.\n\n\"A beautiful generalization has been made to show how well this idea of\nheat harmonizes with the entire plan of the universe. In the whole\nboundless universe each system of worlds, like our solar system, may be\nregarded as a molecule, or complex atom. These cosmical molecules, or\ncomplex atoms of the universe, are in motion through unmeasured space. In\nthese systems of worlds the planets, with their satellites, are the\nmolecules, and they are in motion--indeed, they commonly have several\nmotions. Our earth, for example, rotates upon its axis once each day; it\nrevolves in its orbit around the sun once each year, and the axis of the\nearth has a slow wabbling motion which produces the precession of the\nequinoxes, requiring 25,868 years for a complete revolution. The earth\nalso is made up of parts, and all these are in ceaseless motion. As said\nthe old Greek philosopher, 'All things flow'--that is, everything is in a\nstate of change. Solomon has well described this perpetual movement and\nchange: 'One generation passeth away, and another generation cometh. The\nsun also ariseth, and the sun goeth down, and hasteth to his place whence\nhe arose. The wind goeth toward the south, and turneth about unto the\nnorth. It whirleth about continually, and the wind returneth according to\nhis circuits. All the rivers run into the sea; yet the sea is not full;\nunto the place from whence the rivers come, thither do they return again.\nAll things are full of labor; man cannot utter it. The eye is not\nsatisfied with seeing, nor the ear filled with hearing. The thing that\nhath been, it is that which shall be; and that which is done is that which\nshall be done, and there is no new thing under the sun.' Eccles. i. 4-9.\nIt is certainly in harmony with this universal movement that the atoms of\nmatter, though they seem so closely packed, should in their inconceivable\nsmallness through inconceivably minute spaces vibrate, or rotate, or\nrevolve through an orbit, never at rest. Intensity of heat we may think of\nas intensity of this atomic motion--a wider swing, so to speak, in their\nvibration or revolution. This, of course, requires a wider separation of\nthe atoms and a consequent expansion of bodies. A feebler atomic motion\npermits the atoms to approach each other. In this manner we explain the\nenlargement of bodies by heat and their contraction by decrease of\ntemperature. 'The ideas of the best-informed philosophers are as yet\nuncertain regarding the exact nature of the motion of heat, but the great\npoint at present is to regard it as a motion of some kind, leaving its\nmore precise character to be dealt with in future investigation.' This is\nthe most we can do at present.\"\n\n\"What is the evidence,\" asked Samuel, \"that the dynamic theory of heat is\ntrue?\"\n\n\"The evidence that any theory is true is its ability to explain the facts\nor phenomena with which it has to do. If it explains all the facts and\ncontradicts no known principles, it is regarded as true, or at least no\nobjection can be made to it. Let me illustrate. Astronomers had long\ninquired what force or law controlled the movements of the heavenly\nbodies. At length Newton answered, A force of attraction between bodies\nwhich decreases in proportion as the square of the distance between them\nincreases. This explanation has been found sufficient to explain all the\nknown facts in the working of the heavenly bodies. Upon the basis of this\ntheory astronomers calculate the positions of planets and comets for years\nand centuries to come.\n\n\"This theory led to the discovery of the planet Neptune, the last\ndiscovered of the primary planets. For thirty years irregularities in the\nmotion of Uranus had been noticed. These variations were so slight that if\nanother planet had revolved in the proper orbit of Uranus they would have\nseemed to the naked eye, throughout their course, one and the same star.\nThis slight irregularity of motion was so nicely measured that the place\nof the unseen planet which caused it was almost exactly calculated from\nthe estimated force and direction of its attraction. This theory of a\nuniversal attraction of gravitation so well explains all the facts in the\ncase, and has become so universally received, that we are liable to forget\nthat, after all, it is nothing but a theory.\n\n\"Our idea of the structure of the solar system was at first only a theory.\nThe astronomer does not see the planets revolving in regular circles\nthrough the heavens and moving around the sun. He only sees the shining\npoints moving back and forth upon the concave vault, doubling and crossing\ntheir tracks apparently in the greatest disorder. How shall their motions\nbe explained? Astronomers have found that the motions of planets revolving\naround a central sun, when seen from one of the planets, must present just\nthese apparent irregularities. This explanation is so full and complete\nthat it is now counted not a theory, but an established fact. The same may\nbe said of the shape of the earth.\n\n\"The dynamic theory of heat explains the phenomena of heat better than\nany other explanation that has been proposed. It explains the radiation of\nheat from the sun or from any other hot body: vibrations or impulses are\npropagated through that ether which is supposed to fill all space. It\nexplains the conduction of heat through solid bodies in the same manner.\nIt explains the expansion of bodies: the atomic motion forces the atoms of\nbodies farther apart. It explains the production of heat by friction or\ncollision, which no other theory is able to do: the shock of the collision\ngenerates this atomic vibration. It explains the production of heat by\ncombustion: the atoms of oxygen and carbon or hydrogen dash against each\nother and generate heat by the collision. This theory explains the\ntransmutation of motion, or living force, and electricity, into heat, and\nthe transmutation of heat into electric or mechanical force. These points\nwill come up again, and I now only refer to them in answering Samuel's\nquestion. The dynamic theory explains the phenomena of heat and its\nrelations to force, light, and electricity exceedingly well, and for this\nreason men look upon it with favor and count it as probably true. If in\nthe progress of scientific investigation it shall be found to explain all\nthe new facts discovered and meet well all the demands made upon it, it\nwill at length be received as an admitted principle in physical science.\nThe _wave_ theory of light and the _vibratory_ theory of sound may be\nlooked upon as thus established.\n\n\"At our next lesson we shall take a rapid review of the effects and laws\nof heat.\"\n\n\n\n\nCHAPTER IV.\n\nHEAT A GIFT OF GOD.\n\n\nThe class is again promptly in place and ready for work.\n\n\"As I announced a week ago,\" said Mr. Wilton, \"we will to-day take a rapid\nreview of the effects and laws of heat. Will you tell us, Peter, the first\nand chief of these effects?\"\n\n\"Yes, sir: combustion.\"\n\n\"What is combustion?\"\n\n\"Commonly the rapid union of oxygen with some combustible substance,\nattended with the evolution of heat.\"\n\n\"Was your answer correct, then?\"\n\n\"No, sir,\" said Peter, blushing; \"I spoke before I thought.\"\n\n\"Will you correct your answer?\"\n\n\"The first and chief effect of heat is expansion.\"\n\n\"That is right. Our sensation of heat is of course only a\n_sensation_--merely the _feeling_ which results from the effects of heat\nupon our nerves--but the chief physical effect of heat is the expansion of\nbodies. The chemical qualities of bodies are not changed: they are not\nmade either heavier or lighter. A sufficiently high temperature renders\nbodies luminous, and then we call them red hot or white hot. Solid bodies\nbegin to be luminous at a temperature of about one thousand degrees. But\nthe one invariable effect of heat, with two or three apparent exceptions,\nis expansion. You may mention, Samuel, some familiar illustrations of the\neffect of heat in expanding bodies.\"\n\n\"The blacksmith heats the wagon-tire in order that it may easily slip over\nthe wheel. If a kettle be filled with cold water, by heating it the water\nis expanded and runs over. I have noticed that the spaces between the ends\nof the successive iron rails upon the railroad are larger in winter than\nin summer, showing that the rails are shorter in winter than in summer.\nWhile skating during the cold winter evenings upon the mill-pond, I have\nseen cracks in the thick ice start and run across the mill-pond with a\nroar almost like thunder. The ice was contracted by the cold till it\ncould no longer fill the whole space between the banks, and being frozen\nfast to the banks, it was torn asunder. The mercury in the tube of a\nthermometer is constantly expanding or contracting by every change of\ntemperature.\"\n\n\"Yes, those are all good illustrations, and we might go on to mention\nothers equally good by the score. In cold countries, during the intense\ncold of winter, the surface of the earth cracks by shrinkage, just as you\nhave seen the ice upon the mill-pond torn in two. The Britannia iron\ntubular bridge over the St. Lawrence at Montreal rises and falls two and\none-half inches on account of greater expansion of the upper surface when\nexposed to the heat of the sun, while a loaded freight train causes a\ndepression of but one-fourth of an inch. A few years since, in order to\nmake some philosophical experiments connected with the rotation of the\nearth upon its axis, a ball was suspended by a wire in the interior of\nBunker Hill monument. By this means it was accidentally discovered that\nthe heat of the sun, expanding the sides of the monument exposed to its\nrays, caused the whole monument to sway back and forth daily.\"\n\nHere Ansel raised his hand.\n\n\"What is it, Ansel?\"\n\n\"I was going to mention the belief of geologists that the mountain ranges\nwere thrown up by the contracting of the earth's crust on account of\ncooling.\"\n\n\"That is an illustration of contraction by loss of heat on an enormous\nscale. The materials which form our globe may have existed in the\nbeginning in a nebulous or gaseous state. There is certainly very good\nreason for believing that the earth was once in a fluid state, the whole\nof its substance molten by intense heat. It is certain that the interior\nis now hot, and portions of it molten. It is by very many believed that\nthe whole interior is molten. The crust of the earth may have been formed\nby cooling. If after an outer crust had been formed, and its temperature\nhad fallen so low as to become nearly stationary, the interior mass\ncontinued to cool, the molten mass would tend to sink away from the crust\nand the crust would sink in upon it by wrinkling. Thus mountains may have\nbeen formed. Along the line of fracture the easiest vents would be formed\nfor volcanoes. But this carries us somewhat aside from our subject, and\nas the expansion of bodies by heat has been sufficiently illustrated, we\nwill leave it. Will some one now state the manner in which the dynamic\ntheory of heat explains this expansion?\"\n\nSamuel answered: \"I think you have already given us the explanation.\"\n\n\"I have briefly referred to it, but you may give it again.\"\n\n\"The atomic motion which is supposed to constitute what we call heat,\nwhatever that motion be, whether a vibration or rotation or revolution,\nrequires that the atoms of bodies shall not be packed in absolute contact,\nand the more intense the agitation or the wider the swing of the vibration\nor revolution, the greater must be their separation. Hence heat expands\nbodies by thrusting their atoms farther apart.\"\n\n\"That will do,\" said Mr. Wilton. \"Let us look now at some of the secondary\neffects of heat. You may mention some of them, Ansel.\"\n\n\"Heat relaxes or overpowers the cohesive attraction of bodies.\"\n\n\"What is cohesive attraction?\"\n\n\"It is that force which binds together the atoms of matter in simple\nsubstances, that is, bodies like iron or copper or silver, composed of but\none kind of substance, or in compound bodies it is the force which unites\nthe compound molecules of matter.\"\n\n\"Give us now some illustrations of the effect of heat in overcoming\ncohesive attraction.\"\n\n\"The blacksmith heats his iron in order to overcome its cohesive\nattraction and render it soft, that he may easily hammer it. The founder\nheats his metal till its cohesion is so far destroyed that it becomes\nfluid and can be poured into the mould. Heat relaxes the cohesive force of\nice and changes it to water, and by farther heating its cohesion is\nentirely overcome and the water is changed to a gas.\"\n\n\"We use heat also in cooking our food,\" spoke up Peter: \"is it not because\nheat destroys the cohesive attraction, and thus softens it?\"\n\n\"If that were the only effect of heat upon food,\" said Mr. Wilton, \"we\nshould be obliged to eat our food hot, for as soon as it cooled the\ncohesion would return and the food would be raw again. The operation of\nheat in cooking is various, and part of the effect is commonly to be\nascribed to the water in which the food is cooked or to that which is\ncontained in it. By the combined agency of heat and water starch swells to\ntwenty or thirty times its original bulk and the minute starch grains\nburst open. In cooking potatoes the starch of the potato absorbs a portion\nof the water that is in it, and thus renders it dry and mealy. The action\nof heat and water upon rice, wheat, and other grains is similar to their\noperation upon starch. In the baking of bread the starch is converted into\ngum. In boiling flesh the effect is partly due to the solvent powers of\nwater: the juices of the flesh are extracted, the gelatin is dissolved,\nthe fat is liquefied, and the cells in which the fatty matter is held more\nor less burst, the albumen is solidified, and by long boiling the texture\nand fibre of the flesh are destroyed. The albumen of an egg, that is, the\nwhite, coagulates by heat. But in most of these processes the action of\nheat cannot be separated from that of water.\n\n\"But there is another effect of heat very important both in nature and in\nthe arts. What is that?\"\n\n\"The quickening of chemical affinity,\" answered Samuel.\n\n\"That is right: heat is necessary for the operation of chemical affinity.\nPerhaps this is only a weakening of the cohesive force, thus allowing the\nchemical attractions to assert their strength. But the fact is that, while\nin many cases the chemical affinities act with great energy at ordinary\ntemperatures, in other cases they slumber, however closely the substances\nare brought into contact, till their temperature is raised. Samuel, you\nmay mention some illustrations of this principle.\"\n\n\"A few months ago I visited Hazard's powder mills, in Enfield,\nConnecticut, and there learned how gunpowder is made. The charcoal, the\nsulphur, and the nitre are first finely pulverized, then ground together\nfor hours till thoroughly mixed, and afterward pressed together. This mass\nis then broken into grains and the grains polished. But though these\nelements are brought into so close contact, yet they do not combine and\nexplode till heat is applied. The same is true of the combustion of wood\nand coal. The carbon and the hydrogen of the fuel are constantly\nsurrounded with the oxygen of the air, but they do not take fire and burn,\nthat is, they do not combine with the oxygen, till they are raised to a\nred heat, or perhaps even to a higher temperature. If a stove filled with\nburning coal be cooled down to a low temperature by applying ice, the\ncombustion will cease, the fire will go out. Our teacher at the academy on\none occasion heated a steel watch-spring red hot and plunged it into a jar\nof oxygen, and the steel spring began quickly to burn with great fury.\"\n\n\"You have given us good illustrations, Samuel, and that which is true of\ncarbon and hydrogen and oxygen is true of substances in general. The\neffect of heat in producing chemical changes is very important everywhere.\nIt is seen not only in the chemist's laboratory and in the artisan's shop,\nbut also in the laboratory of Nature. Plant a grain of corn in midwinter:\nwhy does it not germinate and grow? Nothing is needed but the requisite\nheat to quicken the chemical affinities into action. Earth and air furnish\nthe needed material for the growth of forest trees in winter as well as in\nsummer, but the cold holds in check the chemical forces and prevents the\nrequisite chemical combinations. No sooner does the sun quicken that\natomic vibration or revolution which we call heat than vegetable growth\nbegins. Heat is necessary for those chemical changes by which food is\ndigested in the stomach and the processes of nutrition carried on in every\npart of the body. If a man finish his dinner with ice cream or ice water,\nthe process of digestion is delayed till the contents of the stomach\nrecover their proper temperature. This is one chief reason why warm,\ncomfortable clothing is so very important, especially for children. All\nthe vital processes are chemical processes: they are carried on through\nchemical affinities. Unless the body be kept at a suitable temperature,\nthese processes are feeble and imperfect, nutrition and vital combustion\nare hindered, and diseases are engendered.\n\n\"These, then, are the chief effects of heat. It expands bodies, weakens\ncohesive attraction, and quickens the chemical affinities into activity.\"\n\nAnsel again raised his hand.\n\n\"What do you wish?\"\n\n\"Will you please tell us, Mr. Wilton, how this weakening of cohesive\nattraction is explained upon the dynamic theory of heat?\"\n\n\"I will do so with pleasure. The increased atomic motion in the heated\nbody throws the atoms farther apart, as we have already learned, and by\nthis increase of distance their attraction is diminished. If the earth\nwere twice its present distance from the sun, their attraction for each\nother would be four times less than it now is; if its distance were three\ntimes as great, their attraction for each other would be nine times less.\nThe attraction of gravitation diminishes in proportion as the square of\nthe distance through which it must act increases. Perhaps cohesive\nattraction diminishes according to the same law, though the spaces are so\nsmall that this cannot be demonstrated, but it is certainly weakened by\nthe expansion of bodies through the agency of heat.\"\n\nHere Peter raised his hand.\n\n\"What will you say, Peter?\"\n\n\"Do not men heat and burn bricks, not to soften them, but to harden them?\"\n\n\"That is true,\" said Mr. Wilton; \"but in this there is a process of drying\nas well as of heating, and the hardening is due chiefly to the complete\ndrying by the intense heat. Too great heat will melt bricks while in the\nprocess of burning. I once heard a brick-burner say that he could melt the\nbrick around the arches in his kiln in half an hour, if he pleased to put\nin fuel and let the fire burn. Indeed, almost every known solid substance\nhas been fused by heat. Whether carbon has ever been melted is an\nunsettled question.\"\n\n\"I would like to inquire,\" said Samuel, \"why water will not burn. Is it\nbecause it evaporates before it reaches a sufficiently high temperature?\"\n\n\"This is a little aside from our subject, but the incombustibility of\nwater is a provision of the Creator so very important that we will stop to\nnotice it. I think, however, that by a little thought you yourself can\nanswer the question. Tell me again what combustion is.\"\n\n\"Combustion is commonly the combining of oxygen with some other substance\ncalled a combustible. The rusting of iron and the decay of organic bodies\nare forms of slow combustion.\"\n\n\"Now tell us the composition of water.\"\n\n\"Water is composed of oxygen and hydrogen--eight parts of oxygen to one of\nhydrogen, by weight, or two parts of hydrogen to one of oxygen, by\nmeasure.\"\n\n\"How is water formed from these two gases? Are they mixed together as\noxygen and nitrogen are mingled in the air, or are they chemically\nunited?\"\n\n\"They are chemically united: they are burned together. When hydrogen\nburns, the product is water.\"\n\n\"Water is then a _product_ of _combustion_. Can you not now tell why water\nis incombustible?\"\n\n\"I think I now see the reason. The oxygen, being itself the supporter of\ncombustion, will not burn, and the hydrogen has been already once burned\nin the formation of water.\"\n\n\"And that which is true of water is true, in a greater or less degree, of\nother products of combustion. The burning of charcoal produces carbonic\nacid, and carbonic acid will not burn because it is the production of\ncombustion. A candle is extinguished by it as quickly as by water. By a\nrecent invention carbonic acid is used to extinguish conflagrations. The\ncarbon has once united with oxygen, and a second combination with an\nadditional amount, or, as a chemist would say, with another equivalent, of\noxygen is much more difficult.\"\n\n\"I think,\" said Samuel, \"I now understand why water will not burn, but\nwill you please also to tell us why water puts out fire better than\nalmost anything else?\"\n\n\"In order to extinguish fire one of two things must be done: either the\nsupply of oxygen must be cut off or the combustible must be cooled down to\na temperature below the burning point, when the combustion will cease of\nitself. When we shut the draught of an air-tight stove, we check the\ncombustion by shutting off the full supply of oxygen. If we could wholly\nprevent the access of oxygen to the fuel, the fire would at once be\nextinguished. If oxygen should then be admitted again before the fuel had\ncooled down below the burning point, combustion would at once begin again.\nA blazing brand is extinguished by being thrust into ashes, because it is\nshut away from oxygen. In the same way we extinguish the flame of a candle\nwith a tin extinguisher. On the other hand, fires often go out because the\nnecessary temperature is not maintained. Water puts out fire in both these\nways, but especially by the second. Water poured in torrents from a fire\nengine upon a fire forms a film of water, and the burning material shuts\nout the oxygen. But the water acts chiefly by lowering the temperature.\nNo other known substance except hydrogen gas requires so much heat to\nraise it through a given number of degrees of temperature as water. As\nmuch heat is required to heat one pound of water as thirty pounds of\nmercury. Hence, water poured upon burning timber cools it to so low a\ntemperature that it ceases to burn.\n\n\"In addition to this, we may notice that wood saturated with water cannot\nbe heated above the boiling point of water till the water is evaporated.\nAs fast as the wood and the water rise or tend to rise above two hundred\nand twelve degrees, the water changes into steam and carries away the\nadditional heat. The consumption of heat in the formation of vapor we must\nlook at more carefully in a future lesson. We will suppose that a house is\nin flames. A fire engine throws a stream of cold water into the midst of\nthe conflagration. The cold water, dashing against the burning wood, cools\nthe heated surface; it is absorbed into the pores of the wood and hinders\nits rapid heating; a portion of the water, being changed into steam,\ncarries off the heat; the steam, mingling with the flame, lowers the\ntemperature of the burning gas, and in proportion as steam fills the\nsurrounding space oxygen is driven away. A burning coal mine in England\nwas once extinguished by forcing steam into it, thus driving out the air\nwhich supported the combustion and cooling down the burning coal.\n\n\"The advantages which men receive from these agencies of heat are so\nmanifest that we cannot help noticing them. I do not refer to the comfort\nof a pleasant temperature, nor the impossibility of living in a\ntemperature extremely low, but to all those processes by which man subdues\nnature, provides for himself food, clothing, and dwelling-places, and\nbuilds up civilization. Heat is that force which enables man to accomplish\nhis ends. Heat brings the iron from the native ore, and heat renders it\nmalleable and plastic to be shaped for man's uses. Heat quickens the\nchemical affinities and renders the arts of civilized life a possibility.\nHeat brings together oxygen and carbon in ten thousand furnaces, and the\nheat engendered by the combustion, changed to force, drives the ponderous\nor nimble machinery which carries on the work of the world. Heat quickens\nthe chemical affinities and causes the wheat to grow; heat prepares the\nwheat for man's food; and by the aid of heat that food is changed in\nman's body, nutrition goes on, the body is built up, waste matter is\nremoved, and all the vital processes are supported. Without these agencies\nof heat--softening and subduing stubborn matter on the one side, and\nquickening its forces on the other--man could not exist.\n\n\"Let me remind you that these agencies of heat are of God's devising. If\nthe operations of heat are beneficent to man, it is because God wished to\nbless his creatures. I am not much given to moralizing, but when I see how\ncompletely these simple effects of heat meet man's wants, I cannot help\nremembering and admiring the wisdom of the great Designer. It is _God_ and\nnot blind, unconscious Nature that is working.\"\n\n\"This reminds me,\" said Samuel, \"of the tradition in Greek mythology that\nPrometheus stole fire from Jupiter and brought it down to man in a reed as\na precious treasure. It seems to me like a gift from heaven.\"\n\n\"This mythological tradition has, however, one falsehood: there was no\nneed that men should steal fire from the gods; God freely gave it. Heat is\nindeed a gift from heaven.\"\n\n\n\n\nCHAPTER V.\n\nCONVEYANCE AND VARIETIES OF HEAT.\n\n\n\"To-day we review the modes in which heat passes or is conveyed from place\nto place. It is evident that if heat were confined to the very place or\npoint where it is generated, it could subserve none of those uses to which\nit is now applied in the economy of Nature or in the works and arts of\nman. But heat passes from place to place with great facility, and by one\nmethod, with the speed of light, it tends to diffuse itself evenly through\nall; it seeks an equilibrium. The modes of its diffusion, or conveyance,\nare three in number. Ansel may name them.\"\n\n\"Heat passes from place to place and from body to body by 'conduction,' by\n'radiation,' and by 'convection.'\"\n\n\"What is meant, Ansel, by the 'conduction' of heat?\"\n\n\"The passing of heat from atom to atom and from particle to particle\nthrough a body is called conduction.\"\n\n\"That is right. I will call upon Peter to give some illustrations of the\nconduction of heat.\"\n\n\"The examples are so many,\" Peter answered, \"that I hardly know what to\nmention first. If I hold a pin in the flame of a lamp, the part of the pin\nthat touches the flame is first heated, but soon the heat runs along the\nwhole length of the pin and burns my fingers. The parts of a stove which\ntouch the fire are first heated, and from them the heat spreads through\nthe whole stove. A pine-wood shaving, kindled at one end, is heated by\nconduction, but the heat passes through it very little faster than the\nflame follows. Heat escapes from our bodies by being slowly conducted\nthrough our clothing. There is no end to the examples of conduction which\none might give.\"\n\n\"We must not think of the conduction of heat,\" said Mr. Wilton, \"as if it\nwere a fluid slowly absorbed by a porous body, as water poured upon the\nground soaks into it, or as water percolates through a lump of sugar and\nmoistens the whole of it. We must remember that the transfer of heat is\nnot a transfer of any substance, but a transfer of motion. One atom is set\nin motion, and strikes against another atom and sets that in motion, and\nthus motion is communicated from atom to atom and from molecule to\nmolecule through the whole mass of matter till every atom is agitated with\nthe heat vibrations. Do all bodies conduct heat with equal rapidity?\"\n\n\"No, sir,\" replied Ansel; \"there is the greatest possible difference. Some\nsubstances are called good conductors, because heat permeates them so\nreadily and rapidly; others conduct heat very slowly, and are called poor\nconductors or bad conductors.\"\n\n\"That is right. Every child soon learns by experience to make a practical\ndistinction of this kind. He very soon understands that he can hold a\nstick of wood without burning his hand, even though it be blazing at the\nother end, but that when a piece of iron is red hot at one end he must not\ntake hold of it at the other. The child very soon learns to know the\ndifferent feeling of a cotton night-gown from one of flannel, and the\ndifference in apparent warmth between a linen pillow-case and a woolen\nblanket. After a room has been heated for a considerable time the various\nobjects in it all become of the same temperature, and the same is true in\na cold room; but how great the difference in the sensations produced by\ntouching the oil-cloth and a woolen carpet in a cold room! Good conductors\nof heat, if hot, feel very hot; or if cold, feel very cold; while poor\nconductors make a much less decided impression. Why is this, Samuel?\"\n\n\"The good conductors receive heat or part with it very readily. If the\ngood conductor be hotter than our bodies, it imparts its heat rapidly to\nour hand, and because we receive heat rapidly from it, it feels to us very\nhot. Or if it be colder than our bodies, it takes heat from our hands very\nrapidly, and gives the impression of being very cold. Poor conductors\nimpart heat to the skin or take it away more slowly, and hence feel as if\ntheir temperature were more nearly like that of the body.\"\n\n\"The conducting qualities of bodies,\" said Mr. Wilton, \"seem to depend\nchiefly upon their structure or the arrangement of their atoms. Bodies\nwhich are compact and solid in their structure convey heat more rapidly\nthan those which are loose and porous. Hence solids are better conductors\nthan fluids, and fluids are better conductors than gases, and among solids\nthe metals are better conductors than organized bodies, like wood or\nflesh, and better than the loose and porous minerals. In bodies of loose,\nporous, or fibrous texture, the continuity of the conductory substance is\nconstantly broken. The particles in a mass of sawdust touch only at a few\npoints, leaving frequent spaces. In woolen and cotton fabrics the points\nof junction of the fibres are very few, comparatively. For this reason the\nmotion is not readily communicated from atom to atom.\n\n\"The crystalline arrangement of atoms has an influence upon conduction of\nheat. Heat is conducted more rapidly in a direction parallel with the axis\nof crystallization than across that axis. Wood conducts heat more rapidly\nin the direction of the grain. This arrangement seems to be well adapted\nfor keeping trees warm in winter. Their roots reach down into the earth,\nwhich remains warm in the coldest weather. This heat of the earth travels\nalong the fibres up through the tree, while the heat conducted across the\nfibres escapes much more slowly into the open air. The bark also, being a\nvery bad conductor, hinders the escape of heat. Of metals, silver is the\nbest conductor. I will give you a brief table which will show the great\ndifference in the conducting qualities of some of the metals. Counting the\nconducting qualities of silver as 100, the table is: 'Silver, 100; Gold,\n53; Copper, 74; Iron, 12; Platinum, 8; German Silver, 6; Bismuth,\n2.'--_Youmans._\n\n\"What is the second method by which heat passes from place to place?\"\n\n\"It is radiated,\" replied Ansel.\n\n\"And what is radiation?\"\n\n\"It is motion in straight lines or rays diverging from a centre. From a\nhot body heat is passing off in straight lines in every direction. As a\nlamp radiates light, so does a hot body radiate heat.\"\n\n\"Radiant heat,\" said Mr. Wilton, \"moves with the same velocity as light,\nthat is, one hundred and ninety-two thousand miles per second. It also\nfollows the same general principles as light in all its motions. It is\nabsorbed, reflected, or transmitted in the same manner as light. And this\nis true of either luminous heat--that is, heat radiated from a body which\nis red hot--or obscure, or dark heat.\n\n\"As there are good and poor conductors, so there are good and bad\nradiators of heat. The radiation of heat depends upon three conditions:\n\n\"1. Upon the temperature of the body. The higher the temperature, the more\nrapid and energetic is its radiation.\n\n\"2. Upon the surface of the radiating body. A dull, rough surface radiates\nheat more rapidly than a surface bright and polished.\n\n\"3. Upon the substance of the radiating surface. With surfaces equally\nsmooth and bright, some substances radiate heat much better than others. A\nsurface of varnish radiates heat much more powerfully than a surface of\ngold or silver.\n\n\"Ansel, you may, if you can, explain the radiation of heat.\"\n\n\"I can give no other explanation than that radiation is conduction through\nthat subtle ether which is supposed to pervade all space.\"\n\n\"Very well; perhaps that is as good an explanation as can be given. But it\nseems rather like the propagation of an impulse than the spreading of\natomic vibrations in every direction. The motion is propagated in\nstraight lines. If it be conduction, it must be carried on by different\nvibrations from those of ponderable substances. Heat, light, and\nelectricity are supposed to be all propagated through the same theoretical\nether. Sir Isaac Newton estimated the density of the ether as seventy\nthousand times less than the density of our atmosphere, and its elasticity\nin proportion to its density as four hundred and ninety millions times\ngreater. But the very existence of this universally-diffused ether is a\nsupposition made to account for the phenomena of light, heat, and\nelectricity; and, of course, all its qualities must be theoretical also.\nRadiation is believed to be the propagation of a motion or impulse through\nan inconceivably rare and elastic ether.\n\n\"Peter, what is the third method by which heat passes from place to\nplace?\"\n\n\"Convection,\" was his reply.\n\n\"What is meant by convection of heat?\"\n\n\"The conveyance of heat by carrying a heated body. If I remove a hot iron\nor a kettle of hot water, I must of course carry the heat which it\ncontains.\"\n\n\"A very good illustration of the convection of heat,\" said Mr. Wilton,\n\"is seen in the common method of heating water. The heat is applied at the\nbottom of the vessel containing the water; as fast as the water at the\nbottom next the fire is heated, it rises and carries the heat to the top;\ncold water comes to take its place, and this in turn is heated and rises\nand carries heat to the top. This process is carried on till all the water\ncomes to the same temperature. Thus water is heated by convection of heat.\n\n\"A grander illustration is seen in winds and ocean currents. Warm winds\ncarry heat enough to warm a continent, and the mighty ocean currents are\nstill more efficient in transferring heat from one part of the earth to\nanother.\n\n\"Another point we need to understand. When radiant heat falls upon a body,\nwhat becomes of it?\"\n\n\"It is disposed of,\" answered Samuel, \"in one of three ways: it may be\nreflected according to the same principles by which light is reflected; or\nit may be transmitted, that is, pass through the body; or it may be\nabsorbed, that is, stop in it.\"\n\n\"Very well stated, Samuel. In regard to reflection I need to say very\nlittle. You know how light is reflected from a polished surface, such as\na lamp reflector: heat is reflected in the same manner. One fact you must\nbear in mind touching reflected heat: it does not heat the reflecting\nbody.\n\n\"There is no need of telling you that light passes through certain\nsubstances. It passes through gases and through some liquids and some\nsolids. The best of glass, though it is so solid, interposes very little\nhindrance to the passage of light. Heat in like manner radiates through\ncertain solids. Luminous heat is radiated through glass. Rock-salt\ntransmits dark heat also. A plate of alum permits light to pass, but stops\nboth luminous heat and dark heat. Remember that transmitted heat, as was\nsaid of reflected heat, does not heat the body through which it passes. I\nhave seen boys make burning-glasses of ice. The heat passes through them\nand burns that upon which it is concentrated, while the ice itself through\nwhich the heat passes is not melted.\n\n\"If a body have a good radiating surface, that is, if its surface be dull\nand rough, the heat which falls upon it will be mostly absorbed. The\nreflecting and absorbing qualities hold an inverse ratio to each other;\nthe better the reflecting qualities, the worse the absorbing, and the\nworse the reflecting, the better the absorbing. Heat which is absorbed by\na body commonly raises its temperature, and remains in the body till it is\nslowly radiated or is conducted away by the air or other bodies which come\nin contact with it.\n\n\"What is that heat called, Ansel, which is absorbed by a body with no rise\nof temperature?\"\n\n\"It is called _latent_ heat.\"\n\n\"That is the old and common expression, but what is meant by latent heat?\"\n\n\"The word _latent_ signifies _lying hidden_ or _concealed_. Latent heat,\nas you suggested in your first question, is that heat which a body\nreceives without showing it by a change of temperature.\"\n\n\"That name 'latent heat,'\" said Mr. Wilton, \"expresses the opinion of\nthose who invented it; they supposed that heat was in some manner hidden\nin certain bodies. We must not suppose, however, that this latent heat\ncontinues to exist in bodies as heat; latent heat is that heat which is\nconverted into force or some other motion than the atomic heat vibrations,\nand is employed otherwise than in raising the temperature. You will\nunderstand this best by an illustration.\n\n\"Take one hundred pounds of ice at the temperature of thirty-two degrees,\nthat is, as warm as is possible without melting. That one hundred pounds\nof ice will absorb heat which would raise one hundred pounds of ice water\nthrough one hundred and forty degrees, and by receiving that heat it is\nmelted, but the water produced has the temperature of thirty-two degrees.\nIt has received one hundred and forty degrees of heat, but its temperature\nis not raised a single degree. This one hundred and forty degrees of heat\nhas been transmuted into force and employed in overcoming the crystalline\nattraction of the atoms of water.\n\n\"Let that ice water at thirty-two degrees of temperature receive one\nhundred and eighty degrees of heat, and the water rises to two hundred and\ntwelve degrees, the temperature of boiling. But whatever additional heat\nis absorbed brings no increase of temperature, but transforms the water\ninto steam. It is employed in overcoming the cohesive attraction of the\nmolecules of water and changing the liquid to a gas. About one thousand\ndegrees of heat is thus expended, but the steam which is produced has\nonly the temperature of two hundred and twelve degrees. If the process be\nreversed, the steam gives up, as it is said, the one thousand degrees of\nheat in returning to the condition of water and the one hundred and forty\ndegrees in resuming the crystalline structure of ice. The heat which was\nemployed as force in overcoming the atomic and molecular attractions is\ntransmuted again to heat, and shows itself in raising the temperature. And\nthat which is true of water is true of any other substance in changing its\nform from a solid to a liquid or from a liquid to a gas, or the opposite.\nIn an amount different for each kind of matter, in all these changes of\ncondition, heat is transmuted to force or force to heat.\n\n\"These transmutations are going on ceaselessly in the operations of\nNature, and without understanding them we cannot appreciate the wonderful\noperations of heat in the world. The heat of the sun beams upon the ocean;\nthe greater part of that heat is expended as force in overcoming the\nmolecular attraction of water, thus converting it to vapor, and in raising\nthat vapor to the higher regions of the atmosphere. This heat-force, or,\nas we might call it, 'sunpower,' expended upon the earth, amounts to\nthousands of millions of horse-power daily.\n\n\n[Illustration: TRANSMUTATION of HEAT.\n\nPage 113.]\n\n\n\"Examples of the transmutation of force into heat abound everywhere. A boy\nstrikes his heel upon the stone pavement; from the point of contact\nbetween the stone and the steel points in his boot heel sparks of fire fly\nout. Force is changed to heat so intense that particles of steel are set\non fire. Savages who have no better methods of kindling fire rub dry wood\ntogether till the sticks ignite. The force expended in overcoming the\nfriction is changed to heat. In the combustion of coal beneath the steam\nboiler we see both processes going on. The atoms of carbon dash against\nthe atoms of oxygen, and the force of the collision generates the heat of\nthe combustion. This heat, born thus of force, is again transmuted to\nforce, and drives the engine and the machinery attached. In our study of\nGod's management of heat we shall constantly meet with these changes. You\nwill need, therefore, to study carefully this subject of latent heat.\n\n\"Dr. Joule, of Manchester, England, has discovered the ratio between heat\nand force, that is, the amount of force which by transmutation produces\nany given amount of heat. The force of a one-pound weight which has fallen\none foot is taken as the unit of force, and the amount of heat which is\nrequired to raise one pound of water one degree is taken as the unit of\nheat. By many and various careful experiments, Dr. Joule demonstrated that\n772 units of force are the equivalent of one unit of heat. A pound weight\nfalling 772 feet, or 772 pounds falling one foot, and then arrested,\nproduces heat sufficient to raise one pound of water one degree. The\nresult is the same whatever the method by which the force is expended. If\nwater be agitated or shaken, if sticks of wood or iron plates be rubbed\ntogether, if an anvil be struck with a hammer, or if a bar of iron or\ncopper be moved back and forth between the poles of an electromagnet, the\nforce expended is changed to heat. You must remember, however, that force\nbecomes heat only so far as the force is actually expended, or used up so\nthat it no longer exists as force.\n\n\"These conclusions are supported by other beautiful experiments. 'An\nelectric current which, by resistance in passing through an imperfect\nconductor, produces heat sufficient to raise one pound of water one\ndegree, sets free an amount of hydrogen which, when burned, raises exactly\none pound of water one degree. Again, the same amount of electricity will\nproduce an attractive magnetic force by which a weight of 772 pounds may\nbe raised one foot high.'--_Youmans._ We conclude from experiments like\nthese that heat, mechanical force, and electricity are interchangeable\nforces; they may be transmuted the one into another.\n\n\"By this principle of the transmutation of heat and mechanical force we\nexplain the production of heat by compression and the loss of heat by\nexpansion. Samuel, you may state the fact upon this point.\"\n\n\"If any substance be suddenly compressed,\" answered Samuel, \"heat appears;\nif it be expanded, cold is produced. Since gases expand or yield to\npressure so readily, they furnish the best illustration of this\nprinciple.\"\n\n\"The suddenness of the compression or expansion,\" said Mr. Wilton, \"is a\nmatter of no consequence. The effect is the same whether the operation be\nsudden or slow, but if the compression or expansion be slow, the heat or\ncold generated is less apparent; the heat is dissipated as fast as\nproduced and the colder gas is warmed by the vessel which contains it.\nAnsel, how shall we explain this?\"\n\n\"I cannot explain it, sir.\"\n\n\"The explanation is very simple,\" said Mr. Wilton. \"Mechanical force is\nemployed in the compression of the gas; the force is expended and used up\nupon the gas, and appears again in the form of atomic heat motion. In the\nexpansion of gases the operation is just the reverse; the atomic heat\nmotion is expended in producing expansion, and hence disappears as heat.\nThe general principle is that no force can be expended in two ways at the\nsame time.\n\n\"One other point we must notice to-day, that is, _specific heat_. What is\nunderstood, Ansel, by this term, specific heat?\"\n\n\"The relative amount of heat which different substances require to raise\ntheir temperature through any given number of degrees.\"\n\n\"That is right. I think that you all must have noticed that it requires\nmuch more heat to raise the temperature of some bodies than others. What\nan amount of heat is required to raise the temperature of water! That heat\nwhich will raise one pound of water one degree will cause an equal\nincrease of temperature in five pounds of sulphur, or four pounds of air,\nor nine pounds of iron, or eleven pounds of copper, or thirty pounds of\nmercury, lead, or gold. This is what is meant by saying that one substance\nhas a greater capacity for heat than another. The specific heat of water\nis greater than that of any other known substance except hydrogen gas.\nThis fact, taken in connection with its great specific latent heat and its\npoor conducting qualities, renders it exceedingly important in regulating\nclimate and moderating extremes of temperature; of this you will be\nreminded very often as our lessons go on.\n\n\"No law or principle determining the specific heat of the various elements\nand explaining the different capacities for heat has as yet been\ndiscovered. It has been suggested that specific heat depends upon the\nnumber of atoms, that it holds an inverse ratio to their combining\nnumbers, or, what is the same thing, a direct ratio to the number of\natoms. This would harmonize well with the dynamic theory of heat, but the\nharmony between the specific heat of substances and the number of atoms is\nnot sufficiently uniform to establish this supposition.\n\n\"This completes our review of first principles. I hope that this not very\nentertaining review of your academic studies has not wearied you of the\nvery word _heat_ and worn out your interest in examining God's management\nof heat before making a beginning.\"\n\n\"I think,\" said Samuel, \"that we are not in the habit of becoming\ndisgusted with our studies.\"\n\n\"You may expect,\" continued Mr. Wilton, \"if the past has been interesting\nto you, that the lessons to come will prove more interesting still. Next\nweek we shall consider the abundant provision which the Creator has made\nfor warming the earth.\"\n\nAnd let me say to you, patient reader, that if I had known that you were\nas familiar with the laws and principles of heat as Ansel, Peter, and\nSamuel seem to have been, this and the preceeding chapter would not have\nbeen written. However dull this review may have seemed to you, it was\nneedful, perhaps, for others, that they might understand the wonderful\nworks of God which we shall now proceed to examine. And, reader, do not\nforget that heat itself, that subtle motion and mighty force, with all its\nlaws and principles, is one of God's works. Already have we been looking\nat the Creator's handiwork. Already have we been trying to trace out the\nthoughts of God as they are written in the \"Bible of Nature.\" The thoughts\nof God are great and wonderful. It has been useful and interesting to read\nthus far in this book written with the finger of the Creator of worlds and\nof man, even if we turn not another page.\n\n\n\n\nCHAPTER VI.\n\nMANAGEMENT AND SOURCES OF HEAT.\n\n\nWhile the lessons which have been reported were going on, the religious\ninterest in the church was deepening. Mr. Wilton did not cease to make his\nsermons instructive, but, in addition to the instruction, he made them\nmore and more pungent and persuasive. He aimed to gather up the\nimpressions and convictions already wrought in the minds of his hearers\nand combine them for united and immediate effect. He believed that this\nwas to be a reaping-time.\n\nMr. Hume was becoming interested, not because he had been at church, for\nhe had not been there, but the Holy Spirit of God was working upon his\nheart. He was becoming uneasy in his unbelief. For some reason, he knew\nnot why, his opinions were becoming more and more unsettled. He did not\nlike to go to the house of God; his self-will and pride of consistency\nrebelled against the thought of hearing and believing the gospel; but he\nwas restless and discontented away from the place of worship. His\nassociations with his infidel comrades grew distasteful. His Sundays were\ndays of distress: with his attention relieved from business cares,\nthoughts of God and eternity pressed upon him, and he could not escape\nthem. At length he determined to go and hear Mr. Wilton again: perhaps he\nshould hear something which he could so positively reject as to set his\nmind at rest. He went, accordingly, the next Lord's Day, and heard a very\nimpressive sermon.\n\nThe text for the forenoon was Ps. lxvi. 5: \"Come and see the works of God:\nhe is terrible in his doing toward the children of men.\" The sermon gave\nfirst a brief and rapid review of some striking displays of God's\ndispleasure at the sins of men: that ancient world of men whose \"thoughts\nwere only evil continually\" he overwhelmed with the flood; he burned with\nfire from heaven Sodom and Gomorrah, Zeboim and Admah, those lascivious\nand festering cities of the plain; he sent his torturing and consuming\nplagues upon the Egyptians, and sunk the army of Pharoah like a stone in\nthe deep waters of the Red Sea: \"they sank as lead in the mighty waters;\"\nhe caused the earth to open and receive Korah and his adherents, and bade\nhis angel in \"one night\" to touch with death the thousands of\nSennacherib's army. This record of divine wrath against evil-doers has\nstartled the consciences of wicked men, and will continue to startle them\nso long as the ungodly live upon the earth. It is easy for unbelievers to\ncall the word of God a record of fabulous wonders, but that record lives\nand will live, and its words assert their divinity by touching and burning\nthe consciences of men as if they were tongues of fire.\n\n\"But to the thoughtful man,\" said Mr. Wilton, \"there is a manifestation of\nGod's displeasure at sin even more impressive than these miraculous\njudgments. The Creator has built his wrath against sin into the very\nfabric of the universe; he has written it upon the very atoms and elements\nof matter and of mind, and graved it upon the 'nature of things.' The\nforces of Nature are all instinct with holy wrath against ungodliness.\nEvil doing works out evil consequences by the regular course of nature.\nBabylon, Nineveh, and Tyre were great and prosperous, and as mighty in\nwickedness as in commerce and war. In the height of their prosperity God\ndenounced upon them disaster and desolation, and by the natural processes\nof evil their decay and destruction came upon them. No miracle broke the\nharmony of their mighty march to decay and the silence of death. Great\nnations have perished, but not till they became corrupt. Rome fell, but\nluxury first gendered luxuriant vices, and vices enervated her hardihood\nand undermined the defences of her courage. No righteous nation ever\nperished. No nation ever fell into decay till ripe in sin and ready for\nmoral putrefaction. But against wicked and corrupt nations wars and\ndesolations are determined, and the end thereof is with a flood. The very\nforces of Nature seem allied in firm compact with the laws of God, ready\nwith resistless hand to avenge their transgression and to visit evil upon\nevil-doers. This steady march of all the forces of the world in bringing\ndecay and wretchedness upon sinners is more impressive than any single\ndesultory example of avenging wrath.\n\n\"But perhaps an unbeliever replies, 'Not so; there is a natural law of\ndevelopment, decay, and death, apart from sin. Trees grow up, become old,\nand die. Men pass from childhood up to manhood, and from manhood down to\nsecond childhood, and return to the dust whence they came. By a like\nprinciple, nations pass through similar changes of development, decay, and\ndesolation. But in all this there is no manifestation of divine favor or\ndisfavor.'\n\n\"This is narrow and false reasoning. If a single great city had become\ncorrupt while all the world beside remained righteous, and God had\ndenounced his displeasure upon it and had executed his wrath by sudden and\ntremendous judgment, that one city standing out in single and solitary\nungodliness and desolation, who would deny, who could deny, that the fate\nof that unhappy city was a manifestation of divine displeasure? If a\nsecond example were made of a second ungodly city, would the expression of\ndivine wrath be weakened? Nay; every man would say that it is made\nstronger. What if a third example be made of a third city? What if every\nwicked city is made an example? What if God embody his displeasure at\nevil-doing in the structure of the world, and give to the very atoms of\nmatter and the elements of mind such natures that by the working of their\nown proper forces, without a miracle, they shall bring pain and evil,\ndecay and death, upon the ungodly? What is this but writing his wrath\nagainst sin upon the earth and sky, upon matter and the consciences of\nmen, declaring by this that till the heavens and the earth and the spirits\nof men be no more he will never withdraw his indignation? This is what God\nhas done. The wicked man sets in motion the machinery which works out his\nown everlasting undoing. His own hand sows the seeds of death, and as\nthose seeds germinate they strike their roots into his corruptions and\ndraw their nourishment from his evil life. Thus do sinners go on\n'treasuring up wrath against the day of wrath and revelation of the\nrighteous judgments of God.'\n\n\"But remember that God has not left the world in these later ages without\nthe testimony of wrathful judgments which ought to startle and alarm the\nconsciences of the wicked like the fires of Sodom. Let me give you what I\nsuppose to be a true record of the fate which befell a band of bold\nblasphemers. In that uprising of infidelity which took place near the\nclose of the last century there was formed at Newburg, N. Y., through the\ninfluence of a man known as 'Blind Palmer,' an association of infidels\nunder the name of the Druidical Society. The object of the society was to\nuproot and destroy revealed religion. In pursuit of this object they\ndescended to the most blasphemous mockery. At one of their meetings they\nburned the Bible, baptized a cat, partook of the bread and wine as\nappointed for the ordinance of the Lord's Supper, and gave the elements to\na dog. Then the wrath of God broke out upon them. 'On the evening of that\nvery day he who had administered the mock sacrament was attacked with a\nviolent inflammatory disease; his inflamed eyeballs were protruded from\ntheir sockets; his tongue was swollen, and he died before morning in great\nbodily and mental agony. Dr. H----, another of the same party, was found\ndead in his bed the next morning. D---- D----, a printer who was present,\nthree days after fell in a fit, and died immediately. In a few days three\nothers were drowned. Within five years from the time the Druidical\nSociety was organized all the thirty-six original members--actors in the\nblasphemous ceremonies spoken of--died in some strange or unnatural\nmanner. Two were starved to death, seven were drowned, eight were shot,\nfive committed suicide, seven died on the gallows, one was frozen to\ndeath, and three died, the record says, _accidentally_.' Be sure of this:\nGod has not left the world nor forgotten his judgments against his\nenemies, neither is he tied up and hampered by the laws of Nature. 'God is\nangry with the wicked every day. If he turn not, he will whet his sword:\nhe hath bent his bow and made it ready. He hath also prepared for him the\ninstruments of death.'\n\n\"But remember, also, that God does not limit his expression of wrath to\nthese natural agencies. The smile of God beams direct upon the soul as the\nwarm rays of the sun fall upon the cold earth, and the frown of God throws\na shadow which darkens the soul with the gloom of eternal death.\"\n\nThis discourse stirred the mind of Mr. Hume in a wonderful manner. The\nstory of God's judgments upon wicked men and dissolute cities he had read\nmany a time in his boyhood, but the rapid review of them by Mr. Wilton\nseemed to bring them up with a lifelike vividness. And that view of the\nforces of Nature, as allied with the moral laws of God to work out wrath\nupon evil-doers, was new to him, but his own mind quick as thought\nsuggested many more illustrations than Mr. Wilton had time to give. He\nremembered that all manner of vices--drunkenness, lust, devotion to gay,\nsensual pleasures--bring ruin to men. He had noticed that the saddest\nfaces are those of worn-out lovers of pleasure, and he knew that lovers of\npleasure are very quickly worn out--that five years of sensuality will\nwaste the powers of life more than fifty years of good work. He knew also\nthat infidels and blasphemers, whatever else they might be, were unhappy\nmen, and died joyless, foreboding deaths. He was not exactly angry, but\nhis heart rebelled against thus being held by the mighty power of God,\nwilling or unwilling, and against the thought that even Nature herself had\nconspired against him. It seemed to him hard that he was born into such a\nworld, and that there was no escape from it. He did not consider at the\nmoment that God and his works were against him only because he was\nagainst God, and that by submitting to God in loving obedience all the\nforces of God's world and God's providential government would turn in his\nfavor--\"that all things work together for good to them that love God.\"\n\nAt length better thoughts came to him. \"I must know,\" he said to himself,\n\"whether these things are so. I have never examined the subject to\ndiscover the truth, but have tried to find reasons for disbelieving the\nBible and denying the gospel. I ought to look at the other side. If Nature\nand Nature's God have blessings in store for the willing and the obedient,\nwhy should not I know this and receive my share?\"\n\nUnder the impulse of thoughts like these he formed the sudden resolution\nto join Mr. Wilton's Bible class--that is, if he would receive him\nwillingly, of which he had no small doubt. Coming directly forward at the\nproper time, he said to Mr. Wilton:\n\n\"I have learned what your class is studying, and should like, I hardly\nknow why, to join your class for a few Sundays, if you are entirely\nwilling.\"\n\nMr. Wilton, of course, did not know the exact state of Mr. Hume's mind;\nhe did not know but that he came with a contentious spirit to bring up\nobjections and propose hard questions; but he felt certain that, whatever\nhis state of mind, the Spirit of God was bringing him to take this step.\nHe had prayed for him; in prayer his soul had travailed in pain for him;\nand he felt that by way of the throne of grace he had obtained a hold upon\nMr. Hume--that the Holy Spirit had bound a cord between them which could\nnot be broken. He believed, therefore, that, whether he came penitent or\nangry, good would result from his coming. He gave him, therefore, a hearty\nwelcome.\n\n\"I am not only willing,\" he said, \"but very glad, to have you come; and as\nI know that you have kept yourself informed of the latest phases of modern\nscience, I hope we shall have your help in unfolding the subject which we\nare engaged in studying. I think you will be able to do us good.\"\n\n\"Your kind welcome ought certainly to incline me to do anything which I\ncan to help the interest of your study, but I only ask the privilege of\nsitting with your class as a silent listener.\"\n\nThe Sunday-school opened as usual, and the classes entered upon their\nwork.\n\n\"You have come in, Mr. Hume, at just the proper point in the progress of\nour lessons,\" said Mr. Wilton. \"We have been preparing the way by a brief\nreview of the laws of heat. We have gone over the effects of heat; the\nconduction, radiation, and convection of heat; thermal reflection,\nabsorption, and transmission; specific and latent heat. We have tried to\nform a conception of the existence and operations of heat according to the\ndynamic theory that heat is a mode of atomic motion. This review would\nhave had little interest to you. We are now prepared to look at the\ngoodness and wisdom of God in the management of heat. We are not trying to\nprove the existence of a Creator and Governor--we are only looking at the\nmighty and wise works of that God in whom we already believe. We shall\nfind the works of God planned and wrought out with wondrous skill, and\nthat wonderful skill is employed in the interest of goodness. God has\nplanned and wrought for the benefit of his creatures. His wisdom and\ngoodness are exhibited on the grandest scale and in gigantic proportions.\nThis is all that is needed practically to demonstrate the existence of\nGod. A good conscience does the rest. Being once assured that there is a\nCreator, a good conscience leaps to the conclusion that we ought to obey\nand serve him. Nay, the very work and existence of a conscience implies a\ndivine Lawgiver and Ruler. To a good conscience a God is a necessity. But\nas we are not now attempting to show that there is a God, but to study his\nworks, we will pass this point.\n\n\"With respect to the subject before us, let us first notice that heat is a\nnecessity to the world and to man, and that God has made ample provision\nfor that need. What the condition of the world would be without heat we\ncan only conjecture. In the polar regions a natural temperature of seventy\ndegrees below zero has been observed. At this temperature all the water\nupon the globe would turn to ice hard as adamant; all vegetation would\ncease, and with the disappearance of vegetable life all animal life must\nperish. The whole earth would be a frozen, lifeless, silent waste in the\nmidst of silent space. Some lines in Byron's picture of universal darkness\nwould fitly describe the state of the world:\n\n    'The waves are dead, the tides are in their grave,\n    The winds are withered in the stagnant air,\n    And the clouds are perished.'\n\nThis description would be no figure, for motion as well as life depends\nupon heat. Yet seventy degrees below zero is but the beginning of cold.\n'By mixing liquid protoxide of nitrogen with bisulphate of carbon in a\nvacuum, M. Natterer produced a temperature of two hundred and twenty\ndegrees below zero.' At this temperature some of the so-called permanent\ngases--as carbonic acid, chlorine, and ammonia--can be compressed into\nliquids, and it is believed that in the complete absence of all heat all\nthe gases would become solids. But by the agency of heat the world teems\nwith active life. Vegetation clothes the earth with a garment of beauty;\nand earth, air, and sea swarm with living creatures full of enjoyment.\nThis great need of the world is bountifully supplied. The power and wisdom\nof God are employed in producing happiness.\n\n\"This, however, is but a part of the benefit which heat confers upon the\nworld. The chief inhabitant of the earth is man, and man was created for\nsomething higher than bare existence. He was created for civilization and\nculture. The savage state is not, as some self-styled philosophers dream,\nthe natural state of man. Nothing is so much against Nature. The natural\nstate is that condition in which he attains the fullest development. Let a\nbrute be placed in so unfavorable conditions that his growth is dwarfed\nand his natural instincts are not called into exercise, and no one would\nlook upon that as a natural state. But man, wild, uncultured, undeveloped,\nis spoken of as being in his natural state. There could be no greater\nmistake. Culture and civilization are according to Nature, but culture and\ncivilization require that man should get the mastery of Nature and subdue\nher forces. Till man gets the victory over the forces of this rough world,\nhe spends a precarious existence in a hard struggle to gain a meagre\nsupport for his animal life. But when once science brings art, and the\nmastery of Nature is gained, man can rise into culture and beauty.\nOpportunity is given for development. He blossoms into greatness and\nstrength. Ideal and spiritual ends take the place of mere subsistence.\n\n\"But by what agency does man achieve the mastery of Nature? By the agency\nof heat. By the aid of heat man subdues the world. Heat brings the\nlustrous metal from its native ore; heat fashions the metal into a\nthousand shapes for the use of men; heat reigns as king in the curious\nprocesses of the chemist's laboratory, and the laboratory is the mother of\nall those modern arts which bless and beautify human life. By heat man\nprepares his food; by heat he drives his machinery; by heat he outstrips\nthe flight of the winds; by heat he turns winter into summer and in his\nown dwelling makes for himself a perpetual springtime. For these purposes\nof human comfort and culture, God has provided generous stores of heat and\nplaced them under man's control. He has placed in man's hands the means by\nwhich he can generate a heat which devours the hardest metals like stubble\nand a cold greater by far than Nature ever produces. We see that the\nCreator has provided for man as a being susceptible of culture and\ndevelopment, as a being of soul and sentiment, of spirit and aspiration.\nGod has fitted the world to be the dwelling-place of spiritual beings like\nman.\"\n\n\"I beg your pardon,\" said Mr. Hume at this point, \"that the first word I\nspeak in your class should be a question which amounts to an objection.\"\n\n\"I shall be glad,\" said Mr. Wilton, \"to hear your question, even though it\nbe an objection. I will also answer it if I can.\"\n\n\"I wished to ask why it is, if God designed to provide for man's wants,\nthat man can supply his wants, especially his higher wants--the wants of\nhis intellectual and spiritual nature--only with the greatest difficulty\nand toil? The brutes supply their need with comparative ease, but man with\nboundless thought and labor.\"\n\n\"Your question is an important one, and deserves an answer. For myself, I\nlook upon the fact to which you refer as one of the many points in which\nthis world is adapted to human needs. Man is put in a condition which\nrequires boundless thought and toil for the supply of his higher wants\njust because he possesses a nobler nature and such thought and exertion\nare needed for its development. Which is the more desirable condition for\na young man to be placed in--one in which his every wish is anticipated\nand his every aspiration is gratified without exertion on his own part, or\none in which opportunity and means are furnished for self-help, one in\nwhich he can supply his wants and satisfy his aspirations only by the\nexercise of his best abilities? Which will encourage the larger manliness\nand nurture the higher culture and strength? He who has no need for\nexertion rises at best only to a soft and feeble luxury, without mental\nvigor or moral force. What does man need besides scope and reward for\nexertion? Effort and struggle are necessities of our nature. This is\nespecially true of man's higher faculties. Human greatness and goodness\nare not created by a word: they must be developed by exertion. For this\nreason God has made exertion necessary, and as much more necessary with\nman than with the brutes as his culture is more the result of voluntary,\nintelligent exertion. Does this explanation seem to you satisfactory, Mr.\nHume?\"\n\n\"I have no fault to find with it; I must think of it.\"\n\n\"Very well, then; if no other one has a question to ask, we will look at\nanother subject. We will survey the storehouses of heat which God has\nprepared for warming the earth. Samuel, you may name the first great\nsource of heat.\"\n\n\"I think, sir, that the sun is the chief source of heat.\"\n\n\"We certainly receive the larger part of our heat from the sun. No one can\ndoubt this. So much of our heat comes from the sun that the temperature of\nthe earth varies according to the sun's heat, as if that were the only\nsupply. If but a fleecy cloud pass between the sun and the earth, we feel\na decided change of temperature. A few hours less of sunshine each day,\nand a few degrees more of inclination to the sun's rays, change summer to\nwinter and make the difference between the torrid and the frigid zones.\nWithdraw the heat of the sun altogether, and the whole world would become\na desert of frozen death.\"\n\n\"What is the cause of the sun's heat?\" asked Peter.\n\n\"You have asked a question which I cannot answer, and which no man can\nanswer. The most careful and patient observations have been made to\ndiscover if possible the constitution of the sun; learned and curious\nconjectures have been brought forward to explain the source of its heat;\nbut the positive results have not been very large. It is certain that the\nsun is a globe revolving upon its axis in a period of twenty-five days,\nnine hours, and thirty-six minutes. This is known by the motion of dark\nspots upon its surface. The appearance of the sun as seen through a\ntelescope is that of a globe of fire, its surface often in a state of\nviolent agitation and flecked here and there with dark, irregular,\nchangeable spots. These spots are sometimes of enormous dimensions--thirty\nthousand or fifty thousand miles in diameter. They present a dark centre\nwith a narrow border or penumbra of lighter shade. To account for these\nspots, it has been conjectured that the body of the sun is dark, but\nsurrounded by a double envelope of clouds, the outer layer of which is\nintensely luminous. Openings in such enveloping clouds would present an\nappearance like the spots upon the sun. According to this supposition, the\nheat and light of the sun proceed, not from the body of the sun, but from\nthis luminous enveloping cloud. But granting that this supposition is\ntrue, it gives no explanation of the origin of the sun's heat. Laplace\nconjectured that the sun is a globe of fire in a state of violent,\nexplosive conflagration, and that the spots are enormous crater-like\ncaverns in its surface. Newton conjectured that comets falling into the\nsun and being consumed feed the solar fires and maintain its temperature.\nThe reception of the dynamic theory of heat has led to the revival, in a\nmodified form, of this conjecture of Newton. It is suggested that meteors\nor meteoric matter falling into the sun generates its heat by the force of\nconcussion. To show that the intense heat of the sun might be thus\ngenerated, elaborate calculations have been made. It has been demonstrated\nthat if the sun were a solid mass of anthracite coal, its combustion would\nmaintain its heat at its present rate of emission only five thousand\nyears, while the falling of the planet Jupiter into the sun would generate\nan equal amount of heat for thirty-five thousand years. A lump of coal\nfalling from the earth to the sun would produce three thousand times more\nheat by the concussion than by its combustion.\n\n\"The nearest approach that has been made, of an exact and scientific kind,\ntoward determining the constitution of the sun's surface has resulted from\nan examination of the _solar spectrum_. A ray of light, by passing through\na triangular prism of glass, is, as you know, divided into its elements,\nor constituent colors. The ray of light is spread out like a half-open\nfan. This divided and expanded ray, thrown upon a screen, is called the\nspectrum. An examination of the solar spectrum by a microscope shows\ncertain fine dark lines across it. The lines are invariably the same in\ntheir position and grouping. The spectrum of the stellar light is found to\ndiffer from that of the solar light, and the light of one star differs\nfrom that of another star. Light from incandescent metallic vapors gives\nbright lines across the spectrum. Each metal has its own number, position,\ngrouping, and color of these spectral lines. By comparing the solar\nspectrum with the spectra of the various metals--the processes are curious\nand the explanation difficult to be understood--corresponding lines are\ndiscovered, and the conclusion is reached that the sun's atmosphere\ncontains the vapors of several of our well-known metals, as iron, nickel,\nsodium, potassium, and others. This is a most curious and marvelous\nscientific feat, to make an approximate chemical analysis of the sun and\nstars by means of their light. The conclusions, however, seem\ntrustworthy.\n\n\"Can you tell us, Ansel, whether the earth receives heat from the moon and\nstars?\"\n\n\"I cannot, sir.\"\n\n\"I should be glad, Mr. Hume, to have you instruct us upon this point.\"\n\n\"In regard to the fixed stars,\" answered Mr. Hume, \"counting them as the\nremote suns of other planetary systems, we must believe that they radiate\nmore or less heat upon the earth; some indeed have extravagantly\nmaintained that we receive from them nearly as much heat as from the sun.\nThe heat received from them is so small that we perceive no difference\nwhether they be hidden, or shine with their utmost brilliancy. I do not\nknow that investigations have been made to determine scientifically their\nexact thermal influence upon the earth. But little more can be said about\nthe heat of the moon. The light of the full moon, concentrated by a\ntwo-foot burning-glass and thrown upon the bulb of the most delicate\nthermometer, produces no perceptible effect. By means of the electroscope\nor galvanometer, it is said, however, that the moon's heat has been\ndetected. At a late scientific convention held in Chicago, Prof. Elias\nLoomis read a paper, in which he stated that Mr. Harrison of England, by\na comparison of observations made for sixteen years at Greenwich, nine\nyears at Oxford, and sixteen years at Berlin, has discovered that the moon\nexerts a sensible influence upon the temperature of the earth, the highest\ntemperature occurring from six to nine days after the new moon and the\nlowest about four days after the full moon. The conclusion, the opposite\nof what we should naturally expect--the higher temperature occurring when\nthe enlightened face of the moon is turned from the earth--was explained\nby supposing the moon's heat to be dark heat which would be absorbed by\nthe vapors and the clouds, and thus tend to warm and dissipate them. By\nthe dispersion of the clouds, the radiation of heat from the earth's\nsurface would go on more rapidly and the temperature would fall. According\nto this explanation, the lunar heat reduces instead of raising the\ntemperature of the earth. The difference of temperature due to the moon's\ninfluence Mr. Harrison believed to be two and a half degrees. Upon\nextending his calculations through forty-three years of observations made\nat Greenwich, he found the difference reduced to about one degree. As for\nmyself, I confess myself still a skeptic touching the supposed influence\nof the moon upon temperature.\"\n\n\"Upon that subject, I think,\" said Mr. Wilton, \"that we must wait\npatiently for more light. The popular superstitions which refer sickness\nand health, and every kind of good or evil fortune, to the benign or\nmalignant influence of the moon, we, of course, must reject. Samuel, will\nyou name the second chief source of heat?\"\n\n\"I am obliged to answer as Ansel answered just now--I cannot tell. The\nenormous amount of wood and coal burned amounts to something, but this can\nhave very little effect upon the temperature of the earth.\"\n\n\"The second great store of heat is the internal heat of the earth,\" said\nMr. Wilton. \"The importance of this store of heat we can easily understand\nby considering that the earth is a mass of molten mineral matter cooled\nand hardened upon the surface. The crust upon which we live is warmed from\nbeneath by an ocean, or rather a globe, a world, of glowing molten rock.\nDeep excavations have been made in mining operations, and artesian wells\nhave been bored to still greater depths--as deep as two thousand, three\nthousand, or thirty-five hundred feet. The heat of the sun penetrates not\nmore than seventy-five or a hundred feet; below that depth the temperature\nof the earth remains the same throughout the year. Below the point of\nconstant temperature the heat of the earth is found to increase regularly\nand constantly. The rate of increase varies in different regions, but the\naverage rate is about one degree of temperature for each fifty or sixty\nfeet of descent. From this rate of increase it is easy to calculate the\ntemperature at any given depth. At a depth of less than two miles water\nwould boil. At twelve miles in depth the rock becomes incandescent. At\ntwenty-two miles silver melts, at twenty-four miles gold melts, and at\nthirty-five miles cast iron becomes liquid. Volcanic eruptions also\ndemonstrate the existence of immense masses of molten rock in the interior\nof the earth; and we can account for the existence of volcanoes only by\nsupposing that they now communicate or once communicated with the deep\ninterior heat of the earth. The thickness of the earth's crust is,\nhowever, a matter of conjecture. The melting point of different substances\nrises as the pressure upon them increases, and as the density of the rock\nincreases its conducting power becomes greater. The crust of the earth,\ntherefore, may be fifty miles in thickness, or it may be one hundred miles\nor two hundred or three hundred miles. The effect of this internal heat in\nmaintaining the temperature of the earth must be very great.\"\n\n\"I want to ask,\" said Peter, \"how this internal heat came to exist, and\nhow it is maintained?\"\n\n\"This, like your former question, is altogether beyond our knowledge. All\nthat we certainly know is that God made it thus. The process of creation,\nif indeed God did not create the earth by a word, without a process, is a\nmatter of sublimest and most venturesome conjecture. According to the\nopinion of some, the elements of which the earth is composed were created\nseparate and uncombined, and were suffered afterward to unite by their\nchemical affinities. This chemical combination would be nothing else than\na tremendous conflagration, and the result would be the most intense heat\nof which we can form a conception. Others have dreamed of a 'fire-mist'\ncreated of God and by some means condensed into worlds. The temperature of\nthe earth is maintained, so far as we know, only by the poor conducting\nquality of the enveloping crust preventing its cooling. At the present\nrate of radiation, millions of years would be required to render the\nchange of temperature perceptible.\n\n\"What is the third great natural source of heat? I will ask Mr. Hume.\"\n\n\"Mechanical action, or force transmuted to heat.\"\n\n\"Will you please explain this?\"\n\n\"Strictly speaking,\" said Mr. Hume, \"this is not to be counted an original\nsource of heat. But heat is used in the production of winds and waves, the\nflow of rivers, and all the ceaseless activities of the world, and this\nforce reappears from time to time transmuted again to heat. Whenever in\nthe friction of air and of water, in the dashing of matter against matter\nand force against force, motion and force seem to be lost, heat is\nproduced. The water of the sea after long storms is said to be sensibly\nwarmed. We can appreciate the amount of heat generated in this manner only\nby considering in how many thousand ways force is meeting force and motion\nis destroyed. All this lost motion--lost as sensible motion--reappears as\natomic motion, that is, as heat. Such heat has been applied to artificial\nuses. Heat generated by the friction of iron plates ground together has\nbeen used for heating buildings.\"\n\n\"And this transmutation of living force and heat,\" added Mr. Wilton, \"is\nbut one of many illustrations of God's economy in the management of heat.\nNothing is wasted. The voices of Nature all echo the words of Jesus:\n'Gather up the fragments, that nothing be lost.'\n\n\"The fourth source of heat is chemical action. What is the chief form of\nthis which is used for the production of heat? Samuel may tell us.\"\n\n\"Combustion, I think, sir.\"\n\n\"That is right; and the most common form of combustion is the combination\nof carbon with oxygen. This is commonly employed, not because it generates\nthe most intense heat, but because carbon exists so abundantly, and is the\nmost available and the cheapest. The most common form of carbon is wood\nand coal. This is that storehouse of heat which God has placed in man's\nkeeping. Without this the larger part of the earth's surface would be\nuninhabitable. This renders culture and civilization possible. Without it\nthe arts could have no existence. The key of this storehouse of heat God\nhas given to man, so that he may enter in and use its treasures at his\npleasure. In the finer arts where very great heat is required, hydrogen is\nused in place of carbon. Jets of oxygen and hydrogen gas thrown together\nconstitute what is called the oxy-hydrogen blowpipe, and generate the\nintensest heat which can be produced by man.\n\n\"Another source of heat not often mentioned is electrical force. This,\nlike mechanical force, may be transmuted into heat. An electric current\nsent through an insufficient or poor conductor heats it, and, if the\ncurrent be sufficiently strong, consumes it. Thus lightning-rods are\nsometimes melted and buildings set on fire.\n\n\"These, then, are the natural reservoirs of heat: 1, the sun and other\nheavenly bodies; 2, the internal heat of the earth; 3, living force, or\nmotion; 4, chemical action; 5, electric force.\n\n\"We can hardly over-estimate the abundance of these natural supplies of\nheat. The world is warmed on the most munificent scale. The earth receives\nfrom the sun heat sufficient to boil three hundred cubic miles of ice\nwater per hour, and the whole sum of the sun's heat would boil\n700,000,000,000 cubic miles of ice water in the same time, that is, the\nheat radiated by the sun would boil a mass of ice water of the size of our\nglobe in twenty-five minutes.\n\n\"The amount of carbon provided by the Creator is enormous beyond\nconception. Vast regions of country are covered with dense forests, but\nthe fuel from the forests is but a handful in comparison with the fuel\nstored up in coal-beds below the surface of the earth. Mr. Mitchel\nestimated the extent of the coal-beds of a portion of Europe as follows:\nGreat Britain, 12,000 square miles; Spain, 3500; France, 1700; Belgium,\n5180. Mr. R. C. Taylor has made a like estimate for North America, giving\nto British America 18,000 and to the United States 134,000 square miles.\n\n\"These estimates, you will notice, say nothing of Asia, Africa, South\nAmerica, or the islands of the sea, and include only the smaller part of\nEurope. In the United States, also, new coal-fields are constantly\ndiscovered. The supply of carbon for fuel seems exhaustless. In the\nBritish islands about 100,000,000 tons of coal are mined annually. At this\nrate the known supply would last for a thousand years. In the United\nStates the supply has no known limit.\n\n\"You will keep in mind that this supply of heat is also a supply of\nmechanical force. The coal-fields are an exhaustless storehouse of heat\nand power. They warm the dwellings of man and drive millions of engines\nworking with the strength of Titans for human welfare.\n\n\"In this bountiful supply of heat to warm the earth and serve human needs\nmust we not see a kind design on the part of the Creator? God has provided\nthat which the world needs. He has provided without stint or limit. The\ngeneral heating of the globe he accomplishes by his own power. He has\nprovided for human culture, development, and happiness by placing stores\nof heat under man's control. He has furnished scope and means and\nencouragement for achieving greatness and goodness. He has put man in the\ncondition which a wise father would desire for his son.\n\n\"In our next lesson we will look at the preservation and distribution of\nheat, some of the primary elements and arrangements upon which the\ntemperature of the earth depends.\"\n\n\n\n\nCHAPTER VII.\n\nPRESERVATION AND DISTRIBUTION OF HEAT.\n\n\nAnother Lord's Day comes, and the members of the class are, as usual, all\nin their places. They find the subject increasing in interest after\nleaving the review of the laws and principles of heat.\n\n\"A week ago,\" said Mr. Wilton, \"we looked at the chief sources of heat.\nThese are the sun, the internal heat of the earth, chemical action, in\nwhich combustion is most important, electrical action, and mechanical\naction, or 'living force.' The amount of heat furnished from these sources\nis above all comprehension. The Creator seems bountiful even to\nprodigality in supplying heat for the needs of the world and the uses of\nman. But with all this largeness of supply the provision would prove\nwholly inadequate if it were not prudently husbanded and all the avenues\nof waste carefully closed. Men of ample incomes sometimes come to want\nfrom too free expenditure. Their incomes are large, but their expenses are\nlarger. So it would prove in respect to heat if Nature were not as prudent\nin saving as she is bountiful in providing. Will some one mention some of\nthe general methods by which the waste of heat is prevented?\"\n\nNo one answered. Mr. Hume did not think it best to put himself forward in\nanswering questions, and therefore answered only when personally\naddressed. The others were silent because they had nothing to say.\n\n\"I see that I shall have to suggest the answer. Ansel, what part of the\natmosphere is warmest?\"\n\n\"The bottom, I suppose, for the higher a man goes up upon the lofty\nmountains or in a balloon, the colder he finds the air.\"\n\n\"That is right; and we need to ascend only about three miles, even in the\ntropics, to reach the region of perpetual snow, while in the polar regions\nthe line of perpetual freezing comes down to the sea level. What would be\nthe effect, Ansel, if the atmosphere were as warm, or warmer, at the top\nthan at the surface of the earth? How would that affect the rate of\nradiation from the earth?\"\n\n\"It must, of course, increase the radiation very much. With the\ntemperature twenty or fifty or seventy degrees below zero, the radiation\nmust be very little.\"\n\n\"By some means, then, the atmosphere is kept warm at the surface of the\nearth and cold in the higher regions, and in this manner the radiation of\nheat into open space is prevented. This is accomplished notwithstanding\nthat the top of the atmosphere is nearer the chief source of heat, the\nsun. This would be no very easy problem if its solution were left to human\ningenuity. The explanation is very simple, however, when once suggested.\nThe atmosphere is diathermic, that is, it permits the luminous heat from\nthe sun to pass directly through it without heating the air, but the solid\nearth stops the heat by absorption, and is warmed by it. The warm surface\nof the earth imparts, in turn, its heat to the atmosphere resting upon it.\nThis warm air, being expanded by the heat received, becomes lighter than\nthe cold air around, and rises, or rather is forced, upward by the\ngreater weight of the colder air. But as it rises and the pressure of the\nair is diminished it expands still further. By this expansion its sensible\nheat becomes latent, that is, the heat is transmuted into force, and, as\nforce, is incapable of being radiated. In this manner radiation from the\nupper surface of the atmosphere is greatly hindered and waste of heat is\nin a good degree prevented.\n\n\"In respect to this heating of the atmosphere from the surface of the\nearth, a layer of clouds sometimes forms a kind of second surface which\nreceives the sun's rays and warms the air above. A few years ago I saw a\nballoon ascension in Providence, R. I. The day was bleak and chilly, and\nthe sky entirely covered with clouds. The aeronauts were expecting a\nchilly voyage. The balloon shot like an arrow toward the zenith, and in\nfive minutes was completely hidden by the clouds. But to the surprise of\nthe voyagers of the sky, on passing through the clouds their thermometer\nrose ten degrees. This, doubtless, must very often be the case. The air\nabove the clouds must often be warmer than that below.\n\n\"I think you all must have noticed illustrations of this principle on a\nsmall scale. Have you not seen that snow and ice often melt around straws\nand sticks, the snow or ice remaining still frozen at a little distance,\nas if the sticks and straws were warm and had melted them? Have you not\nseen a dark-colored board covered with ice, and the ice remain firm till\nthe sun shone upon it, and then the ice melt upon the under surface,\nleaving the upper surface unaffected?\"\n\n\"I have seen such things a great many times,\" said Peter, \"and wondered\nwhat the reason was.\"\n\n\"The reason is that ice is _diathermic_. Heat passes through the ice\nwithout warming; but when the rays of heat fall upon the stick or stone or\nboard, the heat is absorbed, the dark body is heated and in turn warms and\nmelts the ice. In the same manner the atmosphere is warmed. The heat-rays\nof the sun pass through the atmosphere and fall upon the surface of the\nearth; the earth is warmed, and in turn warms the air resting upon it.\n\n\"The gases and watery vapor contained in the air also hinder the radiation\nof heat from the earth. Pure atmospheric air is perfectly diathermic to\nboth luminous and dark heat, and vapors and gases are also diathermic to\nluminous heat. But to dark heat some of the gases are almost impenetrable.\nAmmonia stops dark heat almost completely. In a smaller degree watery\nvapor does the same. Gases and vapors thus serve as blankets to keep the\nearth warm. The heat of the sun, being luminous heat, penetrates the\natmosphere with its vapors and foreign gases, and falls upon the earth\nalmost without loss, but, being absorbed by the earth, it becomes dark\nheat, and cannot be radiated back through the same gases and vapors. Vapor\nserves thus as a valve: it admits the heat of the sun to the surface of\nthe earth, but prevents its escape. Prof. Youmans calls watery vapor the\nbarb of heat; it catches the heat of the sun and holds it fast.\n\n\"Who can sufficiently admire the simplicity of these arrangements for\npreventing the radiation of heat into the stellar regions?--and their\nefficiency is no less admirable than their simplicity. Arrangements like\nthese show that the Creator had a definite object in view, and that object\nis benevolent. For the advantage and enjoyment of the inhabitants of this\nworld these arrangements were made.\n\n\"We ought at this point to look at those adjustments by which the earth\nreceives just the amount of heat needed to maintain the requisite\ntemperature. The importance of maintaining some certain average\ntemperature cannot be over-estimated. Every animal and plant has its own\n_habitat_--that is, its natural dwelling-place or location--outside of\nwhich it perishes or maintains a stunted and precarious life. The habitat\nof animals and plants depends in a very great degree upon temperature.\nWhat a panorama would be seen if we could fly like a bird from the equator\nto the poles, and look down upon the ever-changing animal and vegetable\nlife as we pass! How the luxuriant vegetation and flaunting colors of the\ntropics would shade off into the scantier vegetable life and more sober\nhues of the temperate zones, and these in turn die out and disappear in\npolar barrenness! We should see the lion and tiger give place to the bear\nand the wolf, the elephant and camel to the ox and horse, and these to the\nwhite bear and reindeer. This sublime panorama we see, in miniature, in\nascending lofty mountains in the tropics. Around the base of the mountain\nflourish the rich and various productions of the torrid zone; a few\nthousand feet of elevation bring us among the productions of the temperate\nzones. The most valuable fruits and grains thrive. Then vegetation becomes\nscanty and stunted, and at last disappears. The top of Mt. Washington,\n6234 feet high, in latitude forty-four degrees, is as bare of trees and\nplants and every form of vegetation as the north pole.\n\n\"The fitting temperature is almost as necessary to the animal tribes as to\nvegetable life. Animals which are native to the tropics do not thrive in\ncolder countries, or if the difference of temperature be very great, they\nperish. A change from a cold to a warm region is equally disastrous. Man\nindeed transfers animals from their natural habitat by protecting them\nfrom the extremes of temperature, but this is, of course, no exception to\nthe general principle of which I am speaking. A change of only a few\ndegrees in the mean annual temperature would render this earth a hard\nplace for even the human race to subsist. But the temperature of the earth\ndepends upon many a wise adjustment--how many, we cannot tell. Will you\ntell us, Samuel, the first adjustment or arrangement upon which the\ntemperature of the earth depends?\"\n\n\"It must depend chiefly I think upon the intensity of the sun's heat.\"\n\n\"Whether or not that be the chief adjustment by which the right\ntemperature is secured, it is at least a very important item. The\nintensity of the sun's heat must, of course, be considered in connection\nwith its distance from the earth. The distance of the sun is no less\nimportant than the power of his rays; indeed, in one sense, it is more\nimportant, for if the intensity of the sun's heat were doubled, the\ntemperature of the earth would be increased only twofold; whereas, if the\nearth were brought to one-half its present distance from the sun, the heat\nwould be increased four times. Heat being one of the radiant forces, its\nintensity diminishes in proportion to the square of the distance through\nwhich it acts. If the earth were 190,000,000 of miles from the sun instead\nof 95,000,000, as it now is, the force of the sun's rays would be\ndiminished fourfold. The Creator has so fixed the distance of the earth\nand sun, and the power of the sun's heat, as to give to this world a\ntemperature suited to its various inhabitants.\n\n\"The temperature of the earth has also some dependence upon our\natmosphere. Can you tell us, Ansel, how the temperature of the earth is\naffected by the atmosphere?\"\n\n\"You have already told us that the atmosphere is _diathermic_, allowing\nthe heat of the sun to fall upon the earth almost undiminished in force.\nIf the air were so constituted as to intercept the sun's rays, it is plain\nthat the earth would receive less heat.\"\n\n\"This adaptation of our atmosphere to transmit the sun's rays,\" said Mr.\nWilton, \"is more subtle than it appears at first sight. It is not merely a\nmatter of depth and density, though those are important considerations,\nnor is it merely a question of the elements of which the atmosphere is\ncomposed. Simple gases are _diathermic_. The atmosphere is therefore made\nup of two simple gases, oxygen and nitrogen, not chemically combined, but\nmixed together. Compound gases intercept the passage of heat. Ammonia,\ncomposed of hydrogen and nitrogen chemically united, almost wholly stops\nit. Even ozone, which is nothing but oxygen in a changed or _allotropic_\nstate, is not _diathermic_. The _diathermic_ quality of the air depends,\nthen, not only upon the fact that it is composed of simple elements\nmingled, but not chemically joined, but also upon the _state_, or\n_condition_, of those simple elements.\n\n\"Another point deserves attention. Oxygen is an element having a wide\nrange of very strong and active affinities. It is ready to unite with\nevery known substance, fluorine excepted. What if some other equally\nactive element were mingled with oxygen to form the atmosphere? What if,\nin place of nitrogen, vapor of sulphur were substituted? What if hydrogen\nwere put in the place of nitrogen? The two elements would combine in\nsudden combustion or explosion, and the atmosphere itself would perish.\nBut nitrogen is a substance so sluggish and inert that it can be brought\ninto union with oxygen only by indirect processes. Because the air is\ncomposed of one so inert element as nitrogen, the atmosphere is preserved,\nand, what is almost as important, it is kept, as it now is, composed of\nsimple elements, and hence _diathermic_. If our atmosphere were a compound\ngas, the world would perish with cold.\n\n\"The temperature of the earth depends also upon certain qualities of the\nearth's surface. I should be glad to have Mr. Hume explain this.\"\n\n\"I suppose,\" answered Mr. Hume, \"that you refer to the qualities of the\nearth as an absorbent and conductor of heat. The earth must needs have the\ncapacity of receiving and retaining the heat which falls upon it from the\nsun. If the earth's surface were polished and brilliant, the heat of the\nsun would be reflected into space as from the surface of a mirror, and\nvery small advantage would the earth receive from the solar heat. A dark\nsoil absorbs heat more readily than a soil of lighter color, and a wet\nsoil, on account of the high specific heat of water, requires more heat to\nraise its temperature than a dry soil. The mineral elements of the soil\nand its compactness or porosity also help to make up its capacity for\nreceiving and retaining heat. The color and constitution of the soil\nsometimes go far toward making the climate of a region. The conducting\nqualities of the earth's crust in its profoundest depths also must be\ntaken into account. If the crust of the earth were composed of silver, or\nany other substance of like conducting quality, and the interior of the\nearth were molten rock, as it now is, the interior heat would be so\nrapidly conducted to the surface that everything upon the earth would be\nconsumed.\"\n\n\"Upon so many circumstances wisely adjusted and nicely blended,\" said Mr.\nWilton, \"does the temperature of the earth depend. The intensity of the\nsun's heat, the dimensions of the earth's orbit, the constitution of our\natmosphere in the subtlest qualities and relations of its elements, and\nthe material, structure, and color of the earth's crust,--on all these and\nmany other things which I cannot stop to mention depends the temperature\nneedful for the well-being of the inhabitants of this globe. I beg your\npardon, Mr. Hume, but allow me to ask whether such a combination of\nagencies and conditions, uniting to work out good for man, does not seem\nto you quite superhuman and worthy of a wise and good Creator?\"\n\n\"I cannot deny it, sir,\" he replied; \"I am not prepared to make any\nobjections. There are many things painful to man in the vicissitudes of\nheat and cold, and if I were to make a world, I suppose I should leave\nthem out, or perhaps make the world upon a very different plan. But I am\nnot prepared to affirm that any changes which I could make would be\nimprovements, though I have thought until recently that more of knowledge\nand power, and perhaps more of chance, too, than of wisdom and goodness,\nwere displayed in the works of Nature. But I must confess my opinion has\nbeen much modified.\"\n\n\"I think your change of mind is in the right direction, and I am glad that\nit is so. We learn the secrets of Nature and appreciate her spirit much\nbetter when we come as reverent questioners than when we come with\npreconceived notions and a patronizing air. I can well understand your\nfeelings and state, for I myself have traveled over the same ground. My\neyes were once dazzled with the glories of science; I worshiped at the\nshrine of natural laws. But I have learned that God is greater than\nNature, the Creator is mightier than the creation. Nature has no mind or\npurpose apart from the plan and will of the supreme Architect and Ruler,\nand this inner plan and purpose of Nature is seen only in the government\nand discipline of our sinful race. I shall greatly rejoice for you and\nwith you if you shall go on to the same end which I have reached.\"\n\n\"I shall much rejoice if I reach some satisfactory and peaceful\nconclusion.\"\n\n\"To understand the management of heat,\" said Mr. Wilton, \"we must take\nnote of the differences and fluctuations of terrestrial temperature. The\nsources of heat are constant. The sun sends out its flood of heat\nuninterrupted and changeless for ever. The internal fires of the earth\ngive an even inward heat. Mechanical and chemical agencies are active\neverywhere. These sources of heat do not fluctuate, flaming up and dying\naway, yet temperature is the most variable of all inconstant things. In\npassing from equator to pole we go from torrid to frigid, from everlasting\nsummer to everlasting winter. And not only this, but in the same region\nthe temperature never remains the same for even twenty-four hours. The\nthermometer may pass from forty degrees above to thirty below zero in a\nvery few hours. We must first consider the agencies by which these\ninequalities are produced. Ansel may mention the first of these.\"\n\n\"The shape of the earth,\" said Ansel.\n\n\"How does the form of the earth operate to produce inequality of\ntemperature?\"\n\n\"The earth is a sphere, and the rays of the sun fall upon it in nearly\nparallel lines. Upon the centre of the hemisphere which is turned toward\nthe sun the rays fall perpendicularly, the sun is directly over head,\nwhile toward the edges of the hemisphere, on account of the curvature of\nthe earth's surface, the rays fall more and more slanting, as if the sun\nwere sinking toward the horizon.\"\n\n\"What is that inequality of temperature which is produced by the shape of\nthe earth?\"\n\n\"The five zones,\" answered Peter.\n\n\"This subject is so well understood,\" said Mr. Wilton, \"that I need not\nspend time in explaining it. Every boy knows the difference between\nsetting his wet slate before the fire to dry so that the heat will fall\nsquarely and perpendicularly upon it and placing it edgewise to the fire.\nUpon the torrid zone the sun shines perpendicularly, upon the temperate\nzones obliquely, and upon the frigid zones still more obliquely, and\nduring a part of the year the sun is entirely hidden. In proportion as the\nrays of heat fall obliquely, any given amount of heat is spread, so to\nspeak, over a larger surface, and the larger the space over which it is\nspread, the feebler it becomes. What is another cause of inequality of\ntemperature?\" No one answered. \"Samuel, what is the cause of day and\nnight?\"\n\n\"The turning of the earth upon its axis.\"\n\n\"And the rotation of the earth upon its axis,\" continued Mr. Wilton,\n\"brings not only an alternation of light and darkness, but also of heat\nand cold. The heat of the sun is withdrawn along with the light. The heat\nof the sun is not withdrawn from the earth, but one-half of the earth's\nsurface is constantly turned away from its influence. This must produce a\ndaily change of temperature. This diurnal fluctuation of temperature may\nbe very small or it may amount to seventy or eighty degrees. Samuel, what\nis a third cause of unequal temperature?\"\n\n\"The inclined position of the earth's axis and the revolution of the earth\naround the sun cause the change of seasons.\"\n\n\"If it were not for this, the earth would still have her zones of seasons;\na part of the earth would have endless summer, a part endless spring, and\nthe rest unbroken winter, but the alternation of seasons at the same place\nwould be unknown. The axis of the earth is now inclined about twenty-three\ndegrees, twenty-seven minutes, twenty-three seconds to the plane of the\nearth's orbit, and as this axis maintains constantly the same position,\nbeing parallel in one part of the earth's orbit to its position in any\nother part of its orbit, during one part of the year the north pole is\nturned twenty-three and a half degrees toward the sun, while in the\nopposite part of the year the south pole is in like manner brought into\nthe light and heat. This causes the sun to appear to move to and fro,\nnorth and south, twenty-three degrees, twenty-seven minutes, and\ntwenty-three seconds from the equator in either direction. The tropics, or\nturning-places, mark the limits of the sun's northern and southern\njourney. Everywhere between the tropics the sun, at some period of the\nyear, passes through the zenith, that is, exactly overhead at noon. North\nand south of the tropics the sun seems to rise higher in summer and to\nsink lower in winter. In summer the sun at midday is about forty-seven\ndegrees nearer the zenith than in winter. Within the polar circles, which\nare the same distance from the poles as the tropics from the equator, the\nheat of the sun is entirely withdrawn during a portion of the year, and\nduring another portion of about equal length the sun does not set. The\nextremes of temperature, caused by the inclination of the earth's axis and\nits revolution around the sun, are very great. In the northern part of\nMinnesota, the temperature rises in summer to one hundred degrees, and in\nwinter sinks to fifty degrees below zero, giving thus an alternation of\none hundred and fifty degrees.\n\n\"In this connection you may also remember that the sun is nearer the earth\nin one part of its orbit than in another part. This difference amounts to\nabout 3,000,000 miles. The sun also remains eight days longer north of the\nequator than south of it. Our summer, therefore, is eight days longer than\nthe summer of the southern hemispheres, and our winters are\ncorrespondingly shorter. These differences tend, however, to balance each\nother, for while the southern summer is shorter, the sun at that time is\nnearer, and while our summer is longer, the sun is more distant. Peter,\nyou may explain to us the effect upon temperature caused by the division\nof the earth's surface into land and water.\"\n\n\"I learned while studying physical geography that the temperature is more\neven upon the sea than upon the land. But why, I do not know.\"\n\n\"The smooth surface of the sea reflects heat better than the rough land:\nfor this reason, a larger proportion of the heat which falls upon the sea\nis not absorbed, but reflected and lost, so far as the temperature of this\nworld is concerned. Water is also a very poor conductor of heat, and has\nwithal a very high specific heat. For these reasons the sea receives and\nparts with heat more slowly than the land, and its absorption or radiation\ncauses a smaller variation of temperature. The result is, therefore, that\nthe sea is cooler in summer and warmer in winter than the land, and the\naverage ocean temperature is lower than the mean continental temperature.\nThe land receives heat more readily and parts with it more rapidly; the\nfluctuations of temperature must therefore be greater. Hence, the\ninteriors of the continents have much greater extremes of temperature than\nthe sea-board. But of the influence of water in equalizing temperature I\nshall have occasion to speak again more at length, and will pass it by for\nthe present. What effect, Peter, has the unevenness of the earth's surface\nupon temperature?\"\n\n\"The higher we ascend upon mountains, the colder we find it.\"\n\n\"That is, Peter, the greater the elevation of any place or country above\nthe sea level, the lower the temperature. Almost the whole surface of the\nearth is an alternation of mountain and hill, valley and plain. One\ncontinent has a very much greater mean elevation than another. One region\nor tract of country lies sloping toward the sun, another is inclined from\nit. The effect in the one case is the same as if the sun were brought more\nnearly overhead; in the other case, the sun is depressed toward the\nhorizon. It is all the same as if the region of country were brought\nnearer the equator or removed farther from it. The effects of the\ncurvature of the earth are obviated or exaggerated. Do clouds tend to\nproduce inequalities of temperature?\"\n\n\"I think they must do this,\" answered Samuel. \"Clouds cover one portion of\nthe earth's surface and shut out the heat of the sun, while other portions\nare well exposed to the sun's rays.\"\n\n\"That is right, Samuel. Does any one think of another cause of inequality\nof temperature?\"\n\nThere was a pause. Then Mr. Hume answered: \"Considering the unmeasured\ncycles of the past, the gradual cooling of the earth has brought a great\nchange of temperature.\"\n\n\"And this change,\" continued Mr. Wilton, \"has been very important for the\nwelfare of the human race. At the present temperature of the earth, the\ncoal-beds, so necessary for the culture and progress of the race, could\nhardly have been formed, and at the temperature of the carboniferous\nperiods, when the coal-beds were deposited, the human race could with\ndifficulty have survived. The high temperature required to prepare the\nearth for man is now no longer needed, but would prove destructive. And\nthis great change of temperature was doubtless caused by the cooling of\nthe earth.\n\n\"The result of all these agencies--the shape of the earth, its daily and\nyearly motions, the inclination of its axis, the eccentricity of its\norbit, the division of its surface into land and water, the varying\nelevation of its surface, and the clouds and storms that hide the sun--is\nthat we have great extremes and rapid transitions of heat and cold, and\nevery variety of climate. These changes of temperature are often painful\nand, unless guarded against, dangerous. Yet, taken as a whole, can one\ndoubt that variety of climate and change of temperature are of advantage\nto man? What weariness and lassitude a changeless temperature would\nbring! How the cooler air of the night comes as a tonic after the\nrelaxation of the heated noonday! Who can estimate the value of our\nnorthern winters, not alone in building up a vigorous and nervous physical\nframe, but in helping the culture of men and nurturing the domestic\nvirtues? We might almost say that her winter evenings have been the making\nof New England. But periods of heat are needed for bringing fruit and\ngrain to ripeness. What variety and richness of productions for the use of\nman the different zones furnish! The supply of man's wants would be\ncomparatively meagre if we had but one zone, even though we had our choice\nof the zones. But every zone is necessary for the perfection of the\ntemperate zones. That we may have the warmth of summer in the temperate\nzones we must have the torrid zone. That we may have the tonic cold of the\ntemperate zones we must needs have the severity of polar winters. I do not\nmean that the Creator could not devise a world that should not have these\npainful extremes, yet enjoy the advantages of the temperate regions. But\nthat would plainly require a world constituted upon principles very unlike\nthose which now prevail. With God this is doubtless possible, but the\nmode is to us inconceivable. But we can easily see that by the present\narrangement of things God has secured many great advantages for man--how\nmany and how great, we can hardly understand--and the apparent\ndisadvantages we cannot positively affirm to be real evils. We can safely\ndeclare that this world is well adapted to man's necessities. But these\ninequalities of temperature are modified and softened by a most\ncomprehensive and beneficent system of agencies by which the extremes are\nprevented from becoming destructive. In this system of compensating\nagencies two great divine ideas are clearly developed, economy in the\nexpenditure of heat and benevolence toward man. Upon this subject we are\nnow prepared to enter.\"\n\n\n\n\nCHAPTER VIII.\n\nMODIFICATION OF TEMPERATURE.\n\n\nResuming the subject where it was left the previous Lord's Day, Mr. Wilton\nsaid:\n\n\"We saw at our last session that the most prominent and permanent features\nof the earth tend to produce differences and great extremes of\ntemperature. These variations of temperature within due limits must be\nregarded as beneficial, if not absolutely essential, to the well-being of\nthe human race. The different zones give the world a richer and more\nvaried supply of food, and finer and more varied plants and animals. The\nchange of seasons gives variety in the experience of life; the warmth of\nsummer ripens the fruit and grain, and the cold of winter tones up the\nphysical strength; nay, the winter's frost is a natural subsoiler,\nloosening up the hard earth and promoting vegetable growth. As for man's\nhigher interests, no one can tell how much the world is indebted to winter\nevenings, to a period of darkness longer than is needed for sleep, and a\nperiod of cold during which the work of husbandry may largely cease.\nLearning, the domestic virtues, and religion are greatly indebted to our\nwinters. But were these agencies which tend to produce inequality of\ntemperature suffered to operate without counteracting influences, the\nextremes of heat and cold would cease to be genial and healthful, and\nbecome destructive. We are now to begin the consideration of those\ncounteracting agencies by which the extremes of temperature are moderated.\n\n\"Let us look first at the daily fluctuation of temperature caused by the\nrevolution of the earth upon its axis. The rotation of the earth brings\nevery place by turns under the influence of the sun's rays, and in turn\nwithdraws it from the heat of the sun, thus producing a daily change of\ntemperature. How is this diurnal change of temperature alleviated?\"\n\nThis was addressed to all, but no one answered. \"Mr. Hume, I should be\nglad to have you suggest the answer.\"\n\n\"There are two chief agencies,\" Mr. Hume replied--\"first, the absorption\nof heat during the day and the radiation of that heat during the night;\nand, secondly, the formation of watery vapor during the day and the\ndeposition of dew by night.\"\n\n\"The first of these agencies,\" said Mr. Wilton, \"is so plain that very\nlittle explanation need be made. During the day, while the sun is shining\nand the temperature is rising, the surface of the earth, the rocks, the\ntrees, and all things are absorbing heat. This heat is, so to speak, laid\nup in store, ready for use in time of need. In due time the sun sinks low\nand sets behind the horizon; the supply of heat is cut off and the\ntemperature begins to fall. Then all those objects which during the day\nwere laying up heat in store begin to radiate heat into the air, and by\ntheir contact with it keep up its warmth. Commonly, the temperature falls\nso low that bodies radiate more heat than they absorb before the setting\nof the sun. In this process water plays a very conspicuous part. You will\ncall to mind what was said before about the large specific heat of water.\nBy means of this, water is able to store up heat in large amounts--larger\nin proportion to its weight than any other substance except hydrogen gas.\nThe heat that is stored up during the day is given off by contact with the\nair and by radiation during the night.\n\n\"But water plays a still more important part in moderating the daily\nfluctuations of temperature by the process of evaporation and the\nformation of dew. Call to mind what was said of the formation of vapor\nwhen we were speaking of latent heat. Heat water to two hundred and twelve\ndegrees--the boiling point: it must still be heated a long time before it\nevaporates. Boiling water must receive five and a half times more heat to\ngive it the form of vapor than to raise it from the freezing to the\nboiling point; that is, about one thousand degrees of heat are required to\nturn boiling hot water to vapor. The same amount of heat is required for\nthe formation of vapor whatever the temperature of the water from which\nthe vapor rises. There is only this difference--vapor from cold water is\ncold, while vapor from hot water is hot. Evaporation goes on more rapidly\nin proportion as the temperature rises, but vapor is formed at all\ntemperatures. Evaporation goes on from ice. The Alpine glaciers, or rivers\nof ice, sink away several feet by evaporation from their surface during\ntheir slow course of many years down the mountain ravines. This process of\nevaporation goes on, I say, during the day, and in the formation of vapor\nan amount of heat which would raise an equal weight of water through one\nthousand degrees of temperature is used up.\n\n\"This vapor which is formed is not supported _by the_ air, as men commonly\nsuppose. It is true that clouds are held up by the atmosphere, but clouds\nare condensed vapor--minute globules of water floating in the air. Vapor\nis invisible. You must have noticed that steam is invisible till it is\ncondensed by contact with the colder air. Vapor rests upon the earth and\nsupports itself by its own elastic force, just as the atmosphere supports\nitself. The presence of air makes no difference with the formation of\nvapor, except that in a vacuum vapor forms very much more rapidly, because\nno air stands in its way. But at any given temperature, in the air or in a\nvacuum, the same amount of vapor rises in due time, and the same amount\ncan support itself. Vapor seems to circulate between the atoms of air, as\nsand fills the spaces between marbles. At the temperature of four degrees\nbelow zero vapor equal to two-thirds of an inch of water can be formed and\nsupport itself by its elasticity; that is, the elastic force of vapor at\nfour degrees below zero is equal to two-fifths of an ounce per square\ninch; at thirty-six degrees vapor equal to two and two-thirds inches of\nwater can support itself; at eighty degrees vapor equal to thirteen inches\nof water can exist; at one hundred and seventy-nine degrees, seventeen\nfeet; and at two hundred and twelve degrees nearly thirty-four feet; that\nis, vapor at two hundred and twelve degrees has an elastic force of\nfifteen pounds to the square inch. Let us suppose that at sunrise the air\nhas a temperature of thirty-six degrees, and that as much vapor is already\nformed as can sustain itself at that temperature. As the sun sheds down\nhis rays the temperature rises and more vapor is formed. We will suppose\nthat half an inch of water is evaporated. Some of this vapor will be\ncarried by ascending currents of air into the higher regions and condensed\ninto clouds, some will be carried by winds into drier and warmer regions,\nyet the amount of vapor will increase during the day. We will suppose that\nduring the night the temperature falls again to thirty-six degrees; all\nthe excess of vapor above two inches and two-thirds of water will be\ncondensed and become dew or fog, and in this condensation the thousand\ndegrees of heat absorbed in the formation of the vapor will be given out\nagain. If vapor equal to one inch of water be condensed, heat is set free\nsufficient to boil a sheet of ice water, five and a half inches in\nthickness, extending over the whole region; that is, it would be all the\nsame as if a fire were kindled on every square rod of land hot enough to\nboil during the night more than twenty barrels of ice water. In this\nillustration I have supposed a larger condensation than commonly takes\nplace, but very much less than is conceivable. Suppose that the\ntemperature is eighty degrees, and that, as is possible, more than one\nfoot of water exists in the state of vapor. Let the temperature fall to\nthirty-six degrees, and full ten inches of water must be condensed,\nsetting free heat which would boil four and a half feet of ice water. So\nlarge a condensation as this never takes place in twelve hours, partly\nbecause the full amount of vapor which might be formed is never actually\nproduced, and partly because the condensation of but a small part of this\nvapor would check the fall of temperature and prevent farther\ncondensation. The supposition that I have made shows the possibilities of\nthis method of moderating extremes of heat and cold. Were it not for these\nprocesses, our days would be much warmer and our nights much cooler than\nthey now are. By the formation of vapor the excess of heat during the day\nis stored up in a latent form; that is, it is used, not as heat, but as\nforce, and is employed in bringing the atoms of water into new\nrelationship; during the night the vapor returns to its former state as\nwater, and the heat-force again becomes sensible heat. Thus the day is\ncooled and the night made warmer.\n\n\"Ansel, have you ever heard the 'dew point' spoken of?\"\n\n\"Yes, sir, I have.\"\n\n\"Do you know what is meant by it?\"\n\n\"That point or degree of temperature at which dew begins to be formed.\"\n\n\"Upon what does the dew point depend?\"\n\n\"Upon the amount of vapor in the air.\"\n\n\"That is right, Ansel. If at any time the full possible amount of vapor\nshould exist, any diminution of the temperature must, of course, cause\ndew to be deposited. Do you know, Ansel, how to ascertain the dew point at\nany time?\"\n\n\"No, sir, I do not.\"\n\n\"There is a beautiful instrument known as Daniell's Hygrometer which shows\nthe dew point as a thermometer shows the temperature. But any one can\neasily determine the dew point without a special instrument for that\npurpose. Pour warm water into a glass pitcher or goblet whose outer\nsurface has been wiped perfectly dry, and polished. Into this set a common\nthermometer. Cool down this warm water by dropping into it small pieces of\nice, and notice carefully when the polished glass begins to be dimmed as\nif it had been breathed upon. When that begins to take place the\nthermometer will show the dew point. In this manner we can determine the\namount of vapor in the air, and by estimating the probable temperature of\nthe night judge of the probability that dew will fall.\"\n\n\"I have noticed some things,\" said Peter, \"about the formation of dew\nwhich I do not understand, and I wish very much to ask about them.\"\n\n\"I should be glad to hear your questions, and will answer them if I can.\"\n\n\"I have noticed that dew falls on clear nights, but not very often on\ncloudy nights. I don't see why that is so.\"\n\n\"Have you ever noticed whether cloudy nights or clear nights are the\nwarmer?\"\n\n\"Cloudy nights are commonly warmer, I think, but I never could see the\nreason for that, either.\"\n\n\"Can you tell why a newspaper spread over a tomato vine keeps the frost\nfrom the vine?\"\n\n\"Because the frost comes upon the paper instead of the vine, of course.\"\n\n\"But why do you say, of course? Why does not the dew--for frost is nothing\nbut dew frozen as it forms--come upon the under side of the paper?\"\n\n\"How could the dew fall upon the under side?\"\n\n\"That is just the point which we need first of all to understand. Men\ncommonly speak of dew as if it fell. I don't know but I have spoken of the\nfalling of dew in this lesson. But dew does not fall at all. The vapor\nsimply touches some cold object, and is condensed upon it. The vapor by\nits elasticity presses against the cold body, and the process of\ncondensation continues until either the body is warmed by the heat set\nfree so that its temperature rises above the dew point, or till the vapor\nis so far exhausted that the dew point falls below the existing\ntemperature. Dew is formed upon the upper surface and not upon the under,\nbecause the upper surface is cool and the under surface is warmer. Beneath\nthe paper spread over the tomato vine, the earth is radiating heat and the\npaper is radiating it back again. If the paper were not there, the heat\nwould be radiated into space and not returned again. The vine would soon\nradiate away its little store of heat, its temperature would sink, below\nthe dew point, and dew or frost would be deposited upon it. The under\nsurfaces of objects are kept warm by the radiation from the earth. In the\nsame manner clouds are wrapped around the earth and keep it warm by\nradiating back its radiant heat. Dew is not formed on cloudy nights,\nbecause they are warmer: the clouds throw back the heat which otherwise\nwould be lost in open space.\"\n\n\"I never knew before,\" said Peter, \"that clouds were of any great use\nexcept to send down rain.\"\n\n\"We shall see in the course of our lessons that clouds are of very great\nuse in warming the earth in other ways, as well as by serving as blankets\nand radiating back the heat which otherwise would escape.\"\n\n\"I wanted also to ask why dew falls--I mean, is formed--on grass and\nleaves of plants while stones are dry.\"\n\n\"I will answer your question by asking another. Did you ever see barefoot\nboys running in the cold dew stop and stand upon a stone or rock to get\ntheir feet warm?\"\n\n\"Oh yes, sir; I have done it myself.\"\n\n\"Why did you stand upon a rock?\"\n\n\"Because I had learned that the rocks would be warm.\"\n\n\"I think that answers your question. The rocks and stones are warmer than\nthe grass and the leaves. The blades of grass and the leaves are thin and\npointed and rough, and have a very large radiating surface. They have but\nlittle heat, and that little they part with rapidly. The rocks and stones,\non the other hand, are bulky, and contain a much larger store of heat,\ntheir radiating surface is comparatively small; only one side is exposed,\nthe other being covered by the warm earth, from which they are drinking in\nheat almost as rapidly as they lose it. They therefore do not lose heat\nenough to sink their temperature to the dew point.\n\n\"So much, then, for the means employed to moderate the changes of\ntemperature from day to night and from night to day. But upon the\nsea-coast and upon certain islands of the sea another agency is employed.\nWill some one suggest what this agency is?\"\n\nNo one else answered, and finally Mr. Hume said: \"I suppose, of course,\nthat you refer to the land and sea breezes?\"\n\n\"This is what I had in mind. During the day the land is warmer than the\nsea, and the breeze from the sea blowing upon the land cools the air.\nDuring the night the land radiates its heat more rapidly than the water,\nand soon the sea becomes the warmer. Then a breeze springs up in the\nopposite direction; the cooler air of the land flows out upon the sea. By\nthis means the air upon the land and the air upon the sea are daily\ncommingled, thus securing a more even temperature upon the land. This\nsoftens the extremes of daily temperature. I make only this brief\nreference to the land and sea breezes, because in another connection we\nshall examine the general subject of winds and their influence in the\nequalization of temperature.\n\n\"The result of all these influences is that the changes of temperature\nfrom day to night and from night to day, while not inconsiderable, are by\nno means destructive, and in many cases are no greater than is refreshing\nand agreeable. These agencies remind us every day of the wise provision of\nthe Creator for the well-being of his creatures. 'Day unto day uttereth\nspeech and night unto night showeth knowledge. There is no speech nor\nlanguage where their voice is not heard.' This care for the earthly\nwell-being of men is but a type of his care for their spiritual happiness.\nThe plan of salvation, and the ways of divine providence working in\naccordance therewith, are more wonderful both in their means and their end\nthan the greatest of the works of Nature. If while we study the natural we\nforget the supernatural, we commit the greatest mistake: we pass by the\ngreater to examine the less. The natural is valuable only as it leads to\nthe spiritual.\"\n\n\n\n\nCHAPTER IX.\n\nTHE MINISTRY OF SUFFERING.\n\n\n\"You must know, Mr. Wilton,\" said Mr. Hume, \"that my mind is full of\nobjections, whether I speak them out or keep silence. I have looked so\nlong upon one side only that I find it hard to look upon other sides also;\nand if there be a Satan, as the Bible teaches, I think he must be\nmarshaling all his legions to overwhelm me by the force of his impetuous\nassaults. I cannot disguise the fact--I do not attempt to disguise\nit--that my mind is not at ease. It used to be at rest, at least\ncomparatively so--not happy, yet not agitated and distressed. My heart was\nnot satisfied, but I believed that my position of unbelief was logically\nimpregnable. But I confess it, my unbelief has of late been shaken. I am\nno longer contented. How I came into this state, I do not know. I am\ncertain that my present unrest was not produced by the force of arguments\nwhich I had heard. It seems to me as if it sprang up uncaused. The old\narguments which I have thought impregnable do not now satisfy me. Why, I\ncannot tell. I think this statement is due to you to explain my position\nin your Bible class, and also to prepare the way for a question which I\nwish very much to propose. I have no objections to make to the marks of\nwisdom and benevolent design seen in the works of creation which I cannot\nmyself answer and remove. Good-will and goodness to the inhabitants of the\nearth lie on the very surface of things; or, if I go beneath the surface,\nI find them no less manifest in the profoundest and subtlest arrangements\nof the universe. If I say, 'This is all the work of chance,' my very\nlanguage is self-contradictory and looks me out of countenance, for the\nvery idea of chance is the opposite of wise and orderly arrangement. The\ndifference between design and chance is that the one works by orderly\narrangements adapted to the accomplishment of a foreseen end, while the\nother shows itself in chaotic disorder, with no adaptation to the\naccomplishment of a purpose. To say that a universe like this, filled in\nevery part with order and beauty, with subtle and unseen elements and\nagencies working out into the boldest relief in the accomplishment of\nbeneficent ends, all minute elements blending in the sublime sweep of the\nuniversal plan,--to say that such a universe is the work of chance is to\nuse language without meaning.\n\n\"If I deny a providential plan in the creation and government of the\nworld, and attribute to brute matter a nature that, by its own inherent\nforce, spontaneously develops into all these contrivances of use and\nbeauty, I see that the wisdom of the whole universe is concentrated in the\nnature of matter, and, if it be possible, infinite subtlety of design is\ndoubly manifest. To create a machine which, upon its elements being thrown\ninto an indiscriminate pile, shall arrange itself, adapt part to part, and\nset itself in motion; which shall repair all its breaks, produce other\nmachines as curious as itself, and thus reproduce itself and perpetuate\nits existence for ever--that would certainly be the acme of intelligent\ndesign.\n\n\"Or if I go farther and deny a Creator, ascribing to the universe an\neternal, uncreated existence, I see that I only entangle myself in a\ncomplication of difficulties. I find myself standing face to face with the\nbest-established facts of geology. If the fact that the animal tribes\nwhich inhabit the earth, and especially the human race, had a beginning be\nnot well established, then no fact in geological science can be reckoned\nas fixed. Geology has overturned the idea of an infinite series of\ngenerations of animals and men. Nor do I see that I gain any advantage or\ngive any explanation of the universe by attributing to matter everything\nwhich others refer to an intelligent and almighty Creator. The distinction\nbetween mind and matter is that mind is endowed with intelligence and\nwill, while matter has neither intelligence nor will, but only blind\nforces, blind attractions and repulsions. If I attribute the order,\nbeauty, design, and benevolence of the universe to mere matter, I clothe\nmatter with the attributes of spirit. In fact, I only set up another God\nand ascribe to the universe a true divinity. I make myself a kind of\npantheist, investing all matter with the attributes of mind and spirit.\nAll this I have pondered over for many a day, and I cannot deny that a\nbelief in an intelligent Creator of the universe is logically more\nsatisfactory. But there is one question which confronts me at every turn.\nI suppose that I might at length work out an answer for myself and that I\nshould now see the explanation if all my thinking for so many years had\nnot been upon the other side.\"\n\n\"I am afraid that I shall not be able to give you satisfaction,\" replied\nMr. Wilton, \"but I shall be glad to hear your question. I can at least\nappreciate your state, and sympathize with you in your groping and\nstruggling. I am glad that you are walking the road you have just\ndescribed. You say that you do not know what has brought you to your\npresent state. I can easily tell you: your experience at this point is not\nsingular; I think the Holy Spirit of God has been leading you and has\nbrought you to your present position. I trust in God that he will lead you\nstill farther. You have great cause for thankfulness and great cause for\ntrembling. Let me caution you: be careful how you treat the divine Spirit;\nwalk softly; be honest, sincere, and simple-hearted as a little child.\n'Except a man become as a little child, he cannot see the kingdom of\nGod.' Above all things, be sincere and straightforward. Deal truly and\nfrankly with the Spirit. If you will only be honest and frank,--honest and\nfrank to yourself, honest and frank to all men, honest and frank with\nGod,--God will soon give you cause to praise him and love him for ever and\never. But what is the question which you wished to propose?\"\n\n\"My difficulty is this: Along with the many arrangements for conferring\nenjoyment and promoting the well-being of man are other arrangements for\nsuffering. Man is made as capable of suffering as of enjoyment, and there\nare appliances provided which are certain to inflict that pain of which\nman is capable. How is this provision for suffering in man and in all\nsentient creatures consistent with the benevolence elsewhere shown? How\nare we to combine these two sets of arrangements in our thinking?\"\n\n\"A full unfolding of the ministry of pain in the good providence of God\nwould lead us entirely aside from our course of study.\"\n\n\"But for me,\" said Mr. Hume, earnestly, \"it would be not at all aside; for\nif I can once see that the provision for suffering made in the\nconstitution of man and of Nature is not repugnant to the idea of a wise\nand good Creator and Disposer of human affairs, I will admit whatever you\nshall have to say afterward, and I shall feel that the gospel of Christ\ncomes to man and comes to me with a moral force which ought not to be\nresisted. I know that I have no right to come into your class and ask you\nto turn aside from your course of study, and the gospel certainly owes\nnothing to me, yet I do hope you will give the opinions which you hold\nupon this subject, if you have formed any positive opinions.\"\n\n\"I am sure,\" exclaimed Peter, \"that we shall all be very glad to have you\nspend the time of this lesson in speaking of this subject.\"\n\n\"But how would it please you if my talk upon the ministry of pain should\nprove to be very much like a sermon?\"\n\n\"I think we like your sermons. I know that we were never so much\ninterested in them as now.\"\n\n\"Very well, then; I will give you, as Mr. Hume says, some of my\nconclusions touching this matter of pain and suffering; and if my opinions\nare not satisfactory or do not cover the facts in the case, it will not\nbe because I have given the subject little thought or have had little\nexperience of suffering. The Lord has led me by a rugged road; he has\ngiven me tears to drink and mingled my cup with weeping. But for this I\nthank him, and I expect, when I shall look back from the life to come upon\nmy earthly course, to see my days of pain and grief shining more brightly\nthan the hours of radiant sunshine.\n\n\"First of all, then, I believe that with the clear exhibition of\nbenevolent design which we see in this world we ought not to doubt the\ngoodness of the Creator, even if we can give no rational explanation of\nthe suffering which abounds. We ought not to believe, we cannot believe,\nthat the Creator's own attributes are self-contradictory and antagonistic,\nthat the same infinite Being is both good and evil, partly benevolent and\npartly malignant. If God is good at all, he is wholly good. Nor can we\nbelieve that a good being and an evil being--God and Satan--hold joint\nsway over the universe and co-operated in the work of creation, and that\nthe good is to be ascribed to the one, and the pain and suffering to the\nother. Whether we can explain it or not, we must believe that there is a\ngood reason for the existence of suffering; unless, indeed, we count the\ninfliction of pain the chief end of the creation, and refer the happiness\nwhich men enjoy to some incidental arrangements not contemplated as\nimportant in the work of creation. But no sane man can think that this\nworld is the work of a demon seeking to fill the earth with groans and\nwretchedness. Our consciences and our reason alike require us to believe\nin the supremacy of goodness.\n\n\"In presenting my views, I of course cannot attempt to prove everything\nfrom the beginning: I must take some things for granted between us. We\nmust start with the admission that there is a God, and that he is a\nrighteous, moral governor. We must at least believe what Paul declares to\nbe needful: 'He that cometh to God must believe that he is, and that he is\na rewarder of them that diligently seek him.' We must also believe our own\nconsciences when they testify that men are responsible, free moral actors,\nand that sin and guilt are not false notions arising from diseased and\nmorbid mental conditions, but realities, true ideas which arise in the\nmind when it works as God designed. Do you freely admit these points of\nbelief, Mr. Hume?\"\n\n\"Yes, sir; I could not ask you to prove every point touched upon in the\nargument, for that would require half a score of volumes, nor will I deny\nthe testimony of my own conscience that there is a God, and that men are\nrightly responsible to him.\"\n\n\"Starting, then, with these fundamental principles, we will look first at\nthe provision made for physical pain. Men and, I suppose, all living\ncreatures are created with the capacity of suffering. The same nerves of\nsensation which if excited naturally give rise to pleasure may be excited\nunnaturally and inflict pain. But why not endow living creatures with\nnerves of sensation which could experience pleasure, but could not feel\npain? Is this possible? Perhaps so, but no man can affirm it with\ncertainty. I do not think that any man can clearly conceive such a thing.\nTo us the capacity of enjoying and that of suffering seem inseparable. But\nthere is no need of insisting upon this point, for the capacity of feeling\npain is a most benevolent provision of the Creator for the benefit of\nliving creatures. It is designed to save life and limb. Pain is the\nsentinel set to guard the outposts of the citadel of life. If there were\nno pain, men would thrust their hands into flames without knowing it. They\nwould indulge in all manner of destructive excesses, and no sufferings\nwould warn them of danger. They would drink poison, and no pain would bid\nthem make haste to take the antidote. Tear men limb from limb, hew them in\npieces with the sword, and no painful sensations would rouse them to\nself-defence. Without this benevolent provision of pain the race of man\ncould hardly be saved from extinction. How much more would this be true of\nthe animal tribes, which are wholly dependent on instinct for guidance and\nimpulse to action! We accordingly find pain possible in those parts of the\nbody where pain can subserve the purpose of protection; elsewhere no\nprovision is made for pain. Nerves of sensation abound in those parts\nwhich require especial care or are especially exposed. The skin is\nexposed, therefore the skin is well supplied with nerves. The parts\nbeneath the skin are less exposed, and are injured only by first wounding\nthe skin; they are therefore less sensitive. The heart, though so very\nimportant, is almost insensible to pain, because the capacity of\nsuffering at that point would confer no protection. The eye is delicate\nand requires the greatest care, and to secure that needed care the Creator\nhas made it delicately susceptible of pain. The sole of the foot, as its\nwork demanded, was made capable of bearing the roughest usage, and hence\nthe sole of the foot is but little supplied with nerves of sensation.\nStill farther, when on account of injury any part of the body requires\nunwonted care, provision is made that the injured part shall become\nespecially sensitive. A bone when well and sound may be cut or sawed\nalmost without pain, but when the bone is injured it becomes inflamed and\nfeels pain most keenly. When a limb for the sake of its own safety ought\nto be kept quiet, Nature makes it painful to move it. For the benevolent\nobject of preserving life and guarding the well-being of living creatures\npain is given. The provision for pain shows the presence of danger, the\nliability of receiving injury, and the kind design of putting men on their\nguard. It is the automatic guardian of our happiness. This is all that I\nhave to say about bodily pain.\n\n\"Mental suffering and pain of conscience are designed, first of all, to\nsubserve the same purpose. The sense of guilt when a man commits a wicked\nact is designed, first, to lead him to repentance. It is the divine alarum\nplaced within the soul to remind men that they have done evil and received\nmoral damage which must be repaired. It is the moral goad which pricks men\nto warn them to turn from wickedness. If evil-doing were as pleasant as\nwell-doing, men would see no difference between right and wrong; all moral\nideas would be subverted and the glory and beauty of man would be trailed\nin the dust.\n\n\"But a guilty conscience continues to trouble wicked men after the day of\nrepentance has passed; Remorse indeed seems to rise up with preternatural\npower when Mercy has withdrawn for ever from the sight of Hope. What is\nthe meaning of this? It means that which we admitted in the beginning,\nthat sinners are guilty in God's sight, that guilt is a real thing and\ndeserves punishment, and that God, the holy and righteous King of men,\ndoes actually punish the guilty. God is holy and abhors sin. Remorse of\nconscience is the shadow of the Creator's frown, the voice of his eternal\nindignation echoing and re-echoing in the soul of man. It is the divine\nwrath penetrating the human spirit and making itself felt. As the holy God\nabhors sin for ever, the wicked must expect to feel that abhorrence for\never. He who puts himself into a rebellious position toward his Creator\nmust stand in that unnatural attitude guilty and suffering. We can\nconceive that this should be otherwise only by subverting the foundations\nof the moral world. Beings created in the image of God, created with a\nconscience and moral affections, created with moral freedom, can attain\nblessedness only by aspiring to heavenly things and becoming God-like. If\nthey break away from the divine will and order, they must suffer the\ndivine frown, they must feel that frown. How can God make his frown felt\nexcept by looking pain, so to speak, into the sinner's conscience?\n\n\"But this whole subject of pain and suffering derives a double\nsignificance from the fact that the human race is a fallen race, alienated\nfrom God by wicked works, yet under a merciful dispensation in which they\nare called to return to obedience. There is no moral quality good and\nbeautiful to our eyes or pleasing to God in which men are not altogether\nlacking, and what is still worse, men grow in evil; their last state is\nworse than the first. There is no healing power in the man which can\nrenovate his heart and bring him back to holiness. It would seem as if\nsome satanic power were hurrying the human race along the road to ruin. If\nmen are to be saved, it must be by a force of renovation outside of\nthemselves, which shall reverse the evil bias of their nature. You say\nthat the world seems fitted to develop man's capacity for suffering, and\nthat this appears to be as much a part of the divine plan as the\nimpartation of happiness. What, think you, would be the result if the\nhuman race were planted in a world where nothing could give pain, where\neverything would afford gratification? What, Mr. Hume, do you think the\neffect would be upon creatures such as we all know men to be?\"\n\n\"I hardly dare answer with the little thought I have given to the subject.\nI would rather listen than speak.\"\n\n\"I have noticed,\" exclaimed Ansel, \"that those boys who have everything\ndone to suit them at home are the most unmanageable in school and the\nmost disagreeable to play with.\"\n\n\"Picture to yourselves,\" continued Mr. Wilton, \"a man who from childhood\nshould have nothing to suffer, no pain or weariness or hardness to bear.\nFrom childhood he has no bodily pain, and the comforts of life are so\ncarefully and bountifully provided that he receives no unpleasant\nsensation. Winter never chills him, summer never heats him. His slightest\nwants are all anticipated. All his sensations are pleasure. Let the same\nbe true of his mind. His will is never crossed; whatever he wishes is\ngiven him; there is no call for self-denial or self-control or abstinence\nor patience. He feels no pressure of need spurring him to exertion. His\nwhole life is enjoyment. His very body would grow up, not strengthened and\ncompacted for exertion, but fitted only for the softness of indolence and\nease. His will would be the selfishness of self-will rather than an\nintelligent, reasonable self-control. There would be no tenderness and\npower of love, no endurance and patience in labor, no strength of moral\npurpose under temptation, no self-denial and self-sacrifice of love for\nthe good of others or for the attainment of a higher blessedness, no\nfaith in God nurtured in darkness and trial. We should have a mushroom\ngrowth of luxurious tastes and indolent ease, impulsiveness and\nimpatience, strength only in selfish, passionate self-will and rampant,\nluxuriant vices. No other result would be possible with creatures like us.\nStrength is developed only under circumstances which call for the exercise\nof strength. A certain hardness and hardihood of living is needed to\ndevelop a manly body. Resolute intellectual exertion in the face of\ndifficulties is demanded to educate the mental faculties. An earthly life\nnot wholly satisfactory is needed to awaken in faithless men a longing for\na better land. We may look upon the sufferings of this world, taken as a\nwhole, as an expression of God's displeasure at sin. How very much is such\nan expression needed! If life were nothing but pleasure, how completely\nmen would forget sin and duty and God and heaven! All the varied\nexperiences of joy and sorrow, of good and ill, of trial and triumph, are\nneeded for man's spiritual discipline. I think you will bear me witness\nthat the noblest, sweetest, most beautiful characters are found in those\nwho have drunk the cup of sorrow to the dregs.\"\n\n\"I cannot deny it, Mr. Wilton. There is old Deacon Smith. We all know\nsomething of his history, I suppose. He was a poor boy; when he was twelve\nyears of age his father died, and his mother died four years later. But he\nworked his way, first to a good education, and then to an honorable\nposition and ample fortune. Then the dishonesty of a partner brought him\nback to poverty too late in life for him to recover himself. Now in his\nold age he works for a small salary in the office of another. But he is as\ncheerful and as grateful as if he had all that heart could wish, and had\nnever in his life suffered a pang. I think he verily believes that\neverything which has befallen him has been an expression of God's love for\nhim. He sheds no tears except for the griefs of others. I think he truly\nrejoices with those that rejoice and weeps with those that weep. As for\nfaith in God, I suppose he would go into a lion's den as calmly as did\nDaniel. If every professor of religion were like him, I am sure that\nnobody could say a word against the gospel. I freely confess that Deacon\nSmith's character has affected me more than all the arguments I have\nheard in favor of Christianity.\"\n\n\"As to that, Mr. Hume,\" replied Mr. Wilton, \"we have both of us,\ndoubtless, seen men who would hate a man the more bitterly in proportion\nas he should show himself Christlike. And as to every church-member being\nlike Deacon Smith, we could hardly expect such a character to be nurtured\nin a day or a year. Deacon Smith has become what he is by a lifetime of\nseverest spiritual discipline and patient endeavor. Such characters are\nwrought out only by a discipline of every form of trial. This world is\nconstituted as it is for the purpose of giving just such a discipline of\neffort and patience.\n\n\"This explanation brings us, however, only to the vestibule of the great\nmystery of suffering in the work of recovering man from the Fall. The\nCaptain of our salvation, who put himself in man's place and took upon\nhimself all human conditions, was made perfect through suffering. The full\npreparation for his work as the Saviour of man called for a discipline of\npain. I shall not attempt to explain this experience of Christ, but\nsalvation brings the believer into a state of profoundest and most\nmysterious union with Christ. The believer must walk in the footsteps of\nJesus. As Christ first came into a condition of sympathy with man, so must\nman come into a condition of sympathy with him. The believer must share\nand repeat, in a feebler way, of course, the experiences of the Lord\nJesus. He must fill up that which is behind of the sufferings of his\nSaviour. By this union with Christ in the discipline of pain the Christian\nis prepared for a union of blessedness. 'If we suffer, we shall also reign\nwith him.' How broad and deep this union of the believer with Christ may\nbe, I cannot tell. I am not able to measure this idea. It seems to me like\none of God's infinite thoughts, revealed in its dimness to overawe the\nsouls of men by its shadowy sublimity--seen only enough to suggest how\nmuch vaster is that which remains unseen--an iceberg, one part standing\nout and nine parts sunk in the unfathomed sea. It is a thought to be felt\nand experienced rather than weighed and measured by human logic. This is\nall that I have to say upon this subject. Do these views commend\nthemselves to you, Mr. Hume?\"\n\n\"I do not know,\" was the reply; \"I want to revolve the subject in my own\nmind. I have received some new ideas, but I judge that a man needs\nexperience in this matter as well as thinking. If I had Deacon Smith's\nexperience of life, I could form a better opinion. As much as this I can\nsee to be true--that provision for bodily pain is a safeguard to the\nhappiness and life of men, and that a world which should anticipate every\nhuman want, leaving nothing to be struggled after and nothing to be\nendured, would have a disastrous influence upon human character. I will\nadmit that the provision for pain is wise and good.\"\n\n\"One other point,\" continued Mr. Wilton, \"we ought to notice before\nleaving this subject. The word of God says, 'We know that all things work\ntogether for good to them which love God,' but it says no such thing of\nthose who do not love him. The afflictions of this life work out for the\nrighteous 'a far more exceeding and eternal weight of glory.' The ministry\nof pain is a ministry of love only to those who submit to Christ. To those\nwho kick at God's mercies the best blessings turn to evils and curses; to\nthe faithful in Christ the greatest griefs and calamities become choice\nblessings. A submissive heart and the agency of the Holy Spirit are\nneeded to sanctify pain. It is a great mistake to think that all men are\nmade better by afflictions. Only the few get good from the discipline of\nlife. With many persons troubles only stir up the worst passions till they\nrage like caged tigers.\"\n\n\"This last remark, Mr. Wilton, has thrown a flood of light upon this\nsubject. But it seems strange to me to find myself saying this. I see how\nit is that so large a part of the pains of life is found in the end to\naccomplish no good. The evil remains evil. Do you think that my long trial\nof doubt and unrest and pain of heart can ever be blessed to my good?\"\n\n\"That it can be so blessed to your good and to the good of many others I\nhave no doubt; but whether it will be, I cannot tell. That depends upon\nyourself, upon your coming through Christ to God as your heavenly Father.\nIt is my earnest prayer that from your unrest of spirit deep peace in\nChrist may break forth; and many others unite in the same.\"\n\n\"I certainly hope,\" said Mr. Hume, \"that my life may not come to nothing.\nIt seems as if something better than a few years of mingled pain and\npleasure, overshadowed by most painful doubt and darkness and followed by\na plunge into nothingness, must be possible for me.\"\n\n\"God give you grace,\" said Mr. Wilton, earnestly, \"to forget the things\nwhich are behind, and reach out your hands toward the worthiest destiny!\nBut remember that there is a destiny more terrible than to cease to be,\nthere is a death deeper and darker than the grave.\n\n    'There is a death whose pang\n      Outlasts the fleeting breath;\n    Oh, what eternal terrors hang\n      Around the second death!'\"\n\nMr. Wilton did not think it best to attempt to draw out Mr. Hume farther\nat that time. He saw that he appeared to be under the guidance of the Holy\nSpirit, and hoped that he would soon experience the new birth by which old\nthings pass away and all things become new. He knew that time is an\nelement even in the operations of the Spirit, and he feared to shake the\nbough too roughly lest the fruit should fall untimely only to wither in\nhis hand. Happily, the superintendent's bell brought the conversation at\nthat point to a natural conclusion.\n\n\n\n\nCHAPTER X.\n\nTRANSPORTATION OF HEAT.\n\n\n\"To-day we come to that subject which we should have looked at a week ago,\nif that I hope not unprofitable discussion of the uses of trials and the\nministry of pain had not prevented. We must now examine the arrangement\nfor softening the rigors of winter and toning down the heat of summer. The\ngeneral principle is that in summer the earth receives an excess of heat,\nwhile in winter the opposite is true. These extremes are mitigated by\ntransferring heat from summer to winter. How is this accomplished? Any one\nwho has thoughts upon this subject may answer.\"\n\n\"I have some thoughts,\" said Ansel, \"but whether right or wrong, I cannot\ntell. I should think heat might be carried from summer to winter in the\nsame way as from day to night.\"\n\n\"What are some of those means for transferring heat which seem to you to\noperate the same in the annual as in the daily changes of temperature?\"\n\n\"One is the absorption and radiation of heat, and another is the\nevaporation of water and the condensation of vapor.\"\n\n\"You are right,\" said Mr. Wilton. \"The effect of these operations in the\nequalization of the annual extremes of heat is in no wise different from\ntheir effect upon the temperature of day and night, but from summer to\nwinter their effect is vaster and more impressive. During the summer, sea\nand land, and 'all that in them is,' are receiving heat and rising in\ntemperature. The heat of summer penetrates and warms the earth nearly a\nhundred feet in depth. Into the sea heat penetrates still deeper. How vast\nthe amount of heat required to warm the whole surface of the earth and sea\nto such depths! By withdrawing so much heat from active use the intensity\nof the summer temperature is softened. During the colder months the land\nand sea slowly radiate their heat. We can hardly over-estimate the effect\nof this alternate absorption and radiation of heat. So great is the\neffect of this stored up heat that the sea and the great lakes never\nfreeze even in the coldest winter weather, except in the polar regions,\nand the temperature must fall far below freezing and continue for a long\ntime below the freezing point before the earth begins to freeze. The great\nbodies of water, remaining always at a temperature above thirty-two\ndegrees, are especially important in warming the wintry air. In the\ncoldest weather they seem like steaming caldrons throwing up their warm\nvapor. It is the absorption and radiation of heat alone which prevent the\ntemperature of the atmosphere from rising or falling suddenly to the\nhighest or lowest point possible. The sun breaks forth in all its splendor\nat noonday in summer: what if the sun were to remain stationary, shining\nthus in his strength for days and months? Everything would be consumed\nwith heat. But why do not the glowing rays of the sun raise the\ntemperature at once to the highest possible point? Because the earth and\nsea and every object upon the earth absorb the heat, storing it up and\nholding it in reserve. On the other hand, when the sun sets and his heat\nis withdrawn, why does not the temperature fall suddenly to the lowest\npossible point? Because the heat held in store is slowly radiated and the\nchange of temperature rendered gradual.\n\n\"In this work of absorbing and radiating heat every object, earth, air,\nand sea, does its appropriate share. But water stands chief, and performs\nthe largest service. Its high specific heat enables it to hold in store\nthe largest calorific treasure, and causes it to change its temperature\nmore slowly.\n\n\"The formation and condensation of vapor also operate in the same manner\nas in the transitions of day and night. During the summer the higher\naverage temperature makes it possible for a much larger amount of vapor to\nbe formed than in winter. You remember that at eighty degrees vapor equal\nto thirteen inches of water can sustain itself, while at thirty-six\ndegrees the elastic force of vapor is equal to the pressure of only two\ninches and two-fifths of water, and at four degrees to three-fifths of an\ninch. If the mean summer temperature at any place were eighty degrees, it\nwould be possible for more than one foot of water to be held in the form\nof vapor. In the formation of this vapor heat would be consumed\nsufficient to boil more than five and a half feet of ice water. If the\nmean winter temperature at the same place be thirty-six degrees, more than\nthree-fourths of this vapor must be condensed and give out its latent heat\nto warm the air. It is not to be supposed that the full amount of vapor\nwhich can support itself does commonly exist, but the difference between\nthe average amount of vapor in summer and in winter must be very great. I\nsuppose this difference often amounts to four or six inches of water. If\nwe suppose it to be four inches, an amount of heat is transferred from\nsummer to winter sufficient to boil twenty-two inches of ice water. In\nestimating the effect of this we must consider that this heat is not given\nout gradually and regularly for three months, but whenever there is a\nsudden fall of temperature vapor is condensed, latent heat becomes\nsensible, and the suddenness and intensity of the fall are diminished. We\nneed also to bear in mind that every open body of water is sending up its\nclouds of vapor constantly. The open lakes, and especially the sea, are\nlike a seething caldron; and thus immensely more vapor is condensed during\nthe winter months than is brought over from summer to winter. Much of the\nvapor formed in winter is to be set to the account of summer, for it is\nthe summer's heat absorbed by the water, which maintains its temperature\nand enables it to throw up such clouds of vapor, even in midwinter. But\nthis comes in more properly at another place, and we will leave it for the\npresent.\n\n\"There is another transition experienced by water by which heat treasured\nup in summer is made available for softening the rigors of winter. Who\nwill suggest it?\"\n\n\"It is the freezing of water,\" said Mr. Hume. \"In the process of\ncrystallization one hundred and forty degrees of latent heat become\nsensible.\"\n\n\"And this,\" continued Mr. Wilton, \"is no inconsiderable matter. Every\npound of water frozen upon the surface of our lakes and rivers, every\npound of water frozen in the wet earth, every pound of water frozen as\nsnow or sleet in the air, gives out as much heat as would boil an equal\namount of water at seventy-two degrees. Have you never heard of setting\ntubs of water in cellars to keep vegetables from freezing?\"\n\n\"I have,\" replied Peter. \"I visited my grandfather two years ago, and his\ncellar sometimes froze. I asked him why he put tubs of water in his\ncellar, but he could not tell me, only he said that he knew that tubs of\nwater in his cellar did keep his vegetables from being nipped with the\nfrost.\"\n\n\"Can you tell us, Peter, why tubs of water set in a cellar should have\nthis effect?\"\n\n\"I suppose that when the water begins to freeze it begins to give out its\nlatent heat.\"\n\n\"That is one part of the reason. The water is drawn from the well at\nperhaps fifty degrees; it must lose eighteen degrees of heat before it\nbegins to freeze, and all the heat which the water loses the air of the\ncellar gains. And then, as you said, as soon as the water begins to freeze\nlatent heat begins to become sensible. Every pound of water frozen sets\nfree heat enough to raise a pound of water through one hundred and forty\ndegrees. But why do not the vegetables begin to freeze as soon as the\nwater?\"\n\n\"I don't know.\"\n\n\"Water holding salt or other minerals in solution freezes at a lower\ntemperature than pure water. For this reason the juices of vegetables and\nfruits and the sap of trees may be cooled below thirty-two degrees\nwithout freezing. On this account the water set in cellars tends to\nprevent vegetables from freezing; the water begins to freeze at thirty-two\ndegrees, while potatoes and turnips may be cooled a little lower than\nthirty-two degrees without harm. In this manner the buds of trees are\nsometimes warmed and protected by the coating of ice which forms around\nthem. The drops of water, falling through the sleety air, touch upon the\ntwigs of trees and freeze upon them, an icy coat embracing them all\naround. In freezing, the water gives out one hundred and forty degrees of\nheat, a part of which goes to the air and a part to the twig.\"\n\n\"This reminds me,\" said Ansel, \"of what the Irishman said on being told\nthat snow contains heat, that 'it would be a blessed thing for the poor if\none could tell how many snowballs it would take to boil a tea-kettle.'\"\n\n\"It might be difficult to use snowballs to boil the tea-kettle, but the\nheat given out in the formation of the snowflakes is doubtless employed\nquite as usefully for the poor as if used in preparing their tea. You have\nall noticed that before a snow-storm, or perhaps during the early part of\nthe storm, the temperature generally becomes milder, and you have often\nheard the remark, 'It is too cold to snow.' Men have learned that the\ncoming of a snow-storm is attended by a warming of the air. This popular\nimpression is philosophical, yet few understand its philosophy. A foot of\nsnow falls, equal to two or three inches of water. In the condensation of\nthe vapor which formed this snow one thousand degrees of latent heat\nbecome sensible, and then in the congelation of the clouds into snowflakes\none hundred and forty degrees of heat are evolved. This softening of the\nrigors of winter is, I think, as great a blessing to the poor as the\nheating of the tea-kettle. Let us make an estimate of the amount of heat\nset free in the production of one great snow-storm. Two feet of snow\nfalls, equal, we will suppose, to five inches of water. In the\ncondensation of the watery vapor one thousand degrees of heat are evolved,\nand in the congelation one hundred and forty degrees--an amount of heat\nwhich would boil three feet of cold spring water. In every square mile\nthere are 27,878,400 square feet, and a square mile of water three feet in\ndepth would contain 83,625,200 cubic feet. The production of such a\nsnow-storm sets free for every square mile of surface heat which would\nboil more than 80,000,000 of cubic feet of spring water. Such a storm\nsometimes extends over a region of country a thousand miles square, that\nis, over a million of square miles. In the production of one such storm--a\nvery heavy and extensive storm, I have supposed--heat is generated which\nwould boil eighty millions of millions (80,000,000,000,000) of cubic feet\nof spring water--an amount altogether too vast for our comprehension. To\naccomplish this result by combustion would require more than 500,000,000\nof tons of anthracite coal--an amount at least three times as great as the\nyearly product of all the coal-mines of the world. And this is but one\nheavy storm. The amount of rainfall in the United States may be thirty-six\ninches or forty or forty-five inches. Supposing the average rainfall of\nthe whole earth to be twenty-four inches--an estimate very far below the\ntruth--we have this result: There are, in round numbers, two hundred\nmillions of square miles of surface, more than five and a half\nquadrillions (5,575,680,000,000,000) of square feet and more than eleven\nquadrillions of cubic feet of water. The condensation of this amount of\nvapor would boil more than sixty quadrillions of cubic feet of ice water.\nOne pound of anthracite coal burned under the most favorable circumstances\nwill boil sixty pounds of ice water. To boil sixty quadrillions of cubic\nfeet of ice water would require sixty quadrillions of pounds of\ncoal--thirty billions of tons--not less than twenty-five tons to every\ninhabitant of the globe. At this rate a very few years would exhaust the\ncoal-fields of the world. Calculations like these are useful in showing\nupon how stupendous a scale the Creator carries on his operations. But we\nmust remember that these works are carried on, not to amaze men, but to\nbenefit them. The works go on silently and unseen, challenging no\nattention from fools, receiving no thought except from the patient student\nof Nature, and eliciting no thankful recognition save from a few reverent\nworshipers.\n\n\"But I have been led away from a point which I had in mind. While\nconsidering the effect of heat in expanding bodies, I reminded you that\nwater presents a marked peculiarity, and promised to speak of it more\nfully. This is the place for us to look at this singular and beautiful\npeculiarity of water. What is the general principle touching the effect of\nheat upon bodies?\"\n\n\"Heat expands bodies and cold contracts them,\" answered Ansel.\n\n\"Water both illustrates this rule and presents some very interesting\napparent exceptions. It contracts by cold like other bodies till it\nreaches the temperature of thirty-nine and a half degrees; it then begins\nto expand, and expands regularly till it falls to thirty-two degrees; at\nthat point it freezes, and in freezing it expands at once about one-ninth\nof its bulk. If the cooling process be continued, the ice produced\ncontracts like any other solid. This peculiarity of the interrupted and\nunequal expansion of water is of the utmost importance in the affairs of\nour world. Consider the result if the water were to contract by cold as do\nother bodies down to the freezing point and below it. Water is cooled from\nthe top by contact with the cold air. As the upper film of water cooled it\nwould sink and a new stratum be brought to the surface; that in turn would\nbe cooled and sink, and thus the cooling process would go on with the\nutmost rapidity till the whole body of water should be reduced to the\nfreezing temperature. Then congelation would begin, and the first\nparticles of ice formed would sink to the bottom, and as fast as the water\nbecame frozen at the top the ice would sink. In this manner a solid body\nof ice would be formed at the bottom of our lakes and rivers, while the\nsurface would remain unfrozen in contact with the cold air till the whole\nbody of water became a compact mass of ice. Great lakes turned to solid\nice would not be thawed during the whole of the summer, for the water\nwarmed from the top would not sink, but would form a warm stratum of water\nupon the surface, while, below, the solid ice would lie hardly feeling the\nsummer heat. Nay, more; in the higher latitudes it would seem as if the\nvery ocean must be turned to solid ice, never to be melted till the end of\ntime. By the singular expansion of water below thirty-nine and half\ndegrees and its great expansion in congelation, these disastrous\nconsequences are prevented. Our lakes are cooled even in winter only to\nthirty-nine and a half degrees; below this temperature the colder water is\nlighter and remains upon the surface; ice floats upon the surface. The top\nbecomes ice, but the great mass of the water remains at thirty-nine\ndegrees, and the inhabitants of the waters live on unharmed. Spring comes,\nand the ice, being upon the surface, is soon melted, and the unbound waves\nbegin again to ripple forth their unconscious joy.\"\n\n\"Do you look upon this irregular expansion and contraction of water,\"\nasked Mr. Hume, \"as a real exception to the rule that heat expands\nbodies?\"\n\n\"Not at all. In freezing, a new force comes in and asserts itself--the\nforce of crystallization; or, more exactly, as the force of heat\ndiminishes the force of crystallization becomes predominant, and throws\nthe atoms into new positions and new relationships. To this new\narrangement of atoms is due the expansion in freezing. Ice contracts and\nexpands by cold and heat the same as any other solid. The attraction of\ncrystallization begins, doubtless, to throw the atoms into their new and\ncrystalline arrangement at the temperature of thirty-nine and a half\ndegrees.\n\n\"We must remember that the heat which is set free in the condensation of\nvapor and in the freezing of water is absorbed in the formation of vapor\nand the melting of water. As much heat is taken from summer as is\nconferred upon winter. The summer is cooled as much as winter is warmed.\nThe formation of vapor is a cooling process. Water is prevented from\nrising above the boiling point by the formation of vapor. Perspiration\ncools us by the evaporation to which it gives rise from the whole surface\nof our bodies. And the higher the temperature, the more rapid the\nevaporation, and the more vigorous the cooling process.\n\n\"We might look at other appliances for transferring heat from summer to\nwinter, but they belong in principle to another department. We have now\nlooked at some of the means for transferring heat in time. The heat is\ntreasured up at the heated noonday, to be brought out for use during the\ncool hours of night; it is garnered from the excessive heats of summer to\nsupply the deficiencies of winter. It is laid up in store to-day to be\nexpended at any future time when needed. The transfer is a transfer not in\nspace, but in time. We must hereafter examine those arrangements by which\nheat is transported through space. Some of these arrangements exert an\ninfluence upon day and night and upon summer and winter, and thus throw\nfurther light upon the subjects already discussed. Already more than once\ntopics have been suggested and their full consideration put off till some\nmore fitting time. In our next lesson we must begin the examination of\nthese new principles. We have before spoken of the vicissitudes of days\nand seasons and years. We shall now have to do with the vicissitudes of\nzones and lands and seas, of deserts and mountain ranges. The elements\nbecome vaster, the stage is broader, and the movements more sublime.\n\n\"I am glad that you are so well interested in these great and beautiful\nworks of God's wisdom and power, but I hope that you do not forget that\nthe crucified Christ is pre-eminently the power of God and the wisdom of\nGod. These natural works are but the husk of which salvation from sin by\nChrist is the kernel. These outward things are wonderful and beautiful for\nthe setting, but the gem, the royal precious stone, the Koh-i-noor, the\n'mountain of light,' for which the setting was made, is the true knowledge\nof the true God and of his Son Jesus Christ. During the past few weeks you\nhave heard others asking, 'What shall we do to be saved?' I should be\ngreatly guilty if I allowed you to think earth, air, and sea, with all\ntheir silent and solemn movements, more important than our spiritual\nattitude toward God the Father and Christ the Saviour. Are you, Samuel, in\nyour interest in studying Nature, forgetting Christ and the souls of men?\"\n\n\"I hope not, and I think not. During the three years since my baptism I\nhave never felt so much my obligation to Christ as now. I never felt\nbefore so deep a desire that my friends should repent and believe in\nJesus. I think the love of Christ constrains me. I have not felt before\nthat my work was very important; I have been expecting to work more\nearnestly by and by; but lately I have felt that Christ gives me something\nto do now for which he holds me responsible.\"\n\n\"What have you tried to do for Christ?\"\n\n\"I have been praying for some of my young friends, and especially for\nAnsel and Peter. And then I felt that I must talk with them as well as\npray for them.\"\n\n\"And can you, my young friends, be careless about your own salvation while\nSamuel is so anxious for you? Are you contented to live 'having no hope\nand without God in the world'? Is your happiness here and hereafter more\nimportant to Samuel than to yourselves?\"\n\n\"We are interested,\" said Ansel. \"We have been talking together about\nbeing Christians, but we don't know what to do.\"\n\n\"They said,\" broke in Samuel, \"that they wished I would ask you to preach\na sermon and tell them what they must do to be saved. They wished to go on\nwith these lessons, but they thought that perhaps you would be willing to\npreach a sermon just upon that subject.\"\n\n\"You know that I often speak of that subject, and when persons have come\nto the inquiry-meeting I have told them what they must do. But I know that\nthere must needs be 'line upon line.' If Ansel and Peter wish it, I will\ndevote a sermon to the subject, and make it as plain as I can. Hardly\nanything gives me more pleasure than to explain the way of salvation when\nI know that my hearers are interested.\"\n\n\"We do wish to have you preach upon that subject, and I am sure that you\nwill have a great many interested hearers besides Ansel and myself.\"\n\n\"But, Samuel, did you not pray for Mr. Hume also, and talk with him?\"\n\n\"I prayed for him, but I was afraid to speak with him. I have tried to\npray for him a double portion because I could not speak with him.\"\n\nTears gathered in Mr. Hume's eyes; the thought came to him that his\nunbelief had raised a barrier between himself and both God and his people.\nThis pious young man was afraid to come to him lest he should meet the\nscornful arguments and cold derision of a proud unbeliever. He felt\nhumbled--he, a subtle, well-read unbeliever, and Samuel a pious lad\nyearning for the salvation of his soul, but daring only to pray in secret\nfor him.\n\n\"Have not you, Mr. Hume, been treating Christ and the Holy Spirit as\nSamuel feared that you would treat him?\"\n\n\"Perhaps so,\" he answered. \"I am sorry that Samuel did not come to me\nfreely. I think he need not be afraid of me now. I also hope you will\npreach the sermon which Ansel and Peter wish to hear.\"\n\nMr. Wilton assured them that he would do as they wished unless the Spirit\nclearly drew him to some other subject. \"I always look,\" he said, \"to the\nHoly Spirit for direction in my preaching. 'When he, the Spirit of truth,\nis come,' said Jesus, 'he will lead you into all truth.' This was\nfulfilled pre-eminently, I suppose, in the inspired men who laid the\nfoundation of the Church, but the Spirit still dwells in believers and\nleads those who love and follow Christ. The preacher of the gospel can do\nnothing without the power of the Spirit of God.\"\n\nAnd I, kind reader, will give you the outline of the sermon if the Spirit\nbids him preach it.\n\n\n\n\nCHAPTER XI.\n\nAN EFFECTIVE SERMON.\n\n\nMr. Wilton preached the sermon spoken of at the close of the last chapter\nthe next Lord's Day morning. The more he thought upon the matter and\ninquired the mind of the Spirit, the more he felt that for a purpose the\nSpirit was calling him to unfold again the authority of God and the\nconditions of salvation. He gave notice of his subject, and invited all\ngood men to pray that he might be able, like a good and wise steward of\nthe mysteries of grace, to bring forth out of the treasure-house things\nnew and old, and that the word might prove as a nail fastened in a sure\nplace by the Master of assemblies. Much prayer was offered, and the people\ncame together in a spirit of unwonted solemnity and earnestness.\n\nMr. Wilton prayed to the glorified Redeemer for his blessing: \"O thou\nexalted Christ, we assemble in thy name and by thine authority. Thou hast\nbidden us not forsake the assembling of ourselves together for thy worship\nand the preaching of thy gospel. By thy grace we enjoy another of these\nsacred days. By thy death thou didst purchase for thy people eternal\nredemption. Thou hast wrought out for them a great and glorious salvation.\nFor thy great love wherewith thou hast loved us thou didst empty thyself\nof divine glories, and madest thyself a servant among servants, and didst\nsuffer in the garden, and die upon the cross, and enter the grave. Now\nthou art exalted at the right hand of the Father, a Prince and a Saviour,\nto give repentance and remission of sins. O thou that judgest men, thy\njustice is great and glorious as thy mercies. Years ago we tested thy\nlove, years ago we felt the shadow of thy wrath; our guilt made us afraid\nand we cried unto thee, and thou forgavest our sins, and didst shed abroad\nthy peace in our hearts. In these recent days thou hast brought other\nsinners to feel their guilt. They have seen thee upon the cross, and have\nbeen smitten with anguish, and have repented, and thou hast received\nthem. Others are bowed down; they mourn; they feel themselves poor and\nneedy; they confess thy justice; they feel the need of thy salvation; they\nwalk in darkness; they grope and find no light; they look unto thee from a\ndistance; but they do not come to thee, they do not follow thee. Wilt thou\nnot draw them to thyself? Wilt thou not bow their pride of heart and turn\ntheir wills and make their hearts tender, gentle, and believing? Wilt thou\nnot smite the rock, and cause the waters of penitent grief to flow? Lay\nthy cross, O Jesus, upon their shoulders and upon their hearts, that they\nmay bear it after thee and share thy glory. Open thou their eyes that they\nmay see eternal destinies and look upon thy divine glories, thy beauty,\nand thy tenderness. Let them follow thee and trust in thee, strengthened\nand comforted by thy rod and thy staff. O Christ, for thine eternal love\nwith which thou hast loved us, reach down thine arm mighty to save and\nlift us up. Lord, save or we perish. And speak thou by thy servant to-day,\nand cause all that hear to recognize the message not as his, but as\nthine.\"\n\nHe read as his text Acts xvi. 30: \"Sirs, what must I do to be saved?\"\n\nHe briefly recited the arrest, imprisonment, and release of Paul and\nSilas. \"The salvation for which the jailer cried out was not deliverance\nfrom the dangers of the earthquake, nor from the displeasure of the Roman\ngovernor. This was the bitter cry of a soul sinking under a load of guilt\nand trembling at the thought of God's impending wrath. Some of you can\nappreciate his feelings and his fears. Your sins against God and Christ\nand the Holy Spirit have risen up before you; they stare you in the face;\nthey condemn you. You feel your guilt--not a light and trifling fault, but\nguilt deep and dark, such as creatures made in the image of God incur by\nrebellion against the blessed and holy Creator. The Holy Spirit has\nrecited the divine law in your ears. Your consciences have heard that\nvoice and echoed its condemnation. You desire to escape that divine\ndispleasure; you desire to have the fires of guilt that burn in your\nconsciences quenched. You cry out, 'Men and brethren, what shall we do?'\nThe answer must be drawn from many parts of the Holy Scriptures.\n\n\"Understand, in the first place, that you are not to be saved by searching\nout some plan of salvation for yourselves. Ask for the old paths. 'He that\nentereth not by the door, but climbeth up some other way, the same is a\nthief and a robber.' 'Other foundation can no man lay than that is laid.'\n'There is but one name given under heaven among men by which we must be\nsaved.'\n\n\"Understand also that it is useless to attempt to save yourselves by\nmaking yourselves righteous. You have tried, I doubt not, to make\nyourselves better. Perhaps you have resolved that you would not come to\nChrist till you can present yourselves in some degree worthy of his care.\nHave you succeeded in getting rid of your sins? Can you blot out your past\nsins? Can you erase the record which stands written in the book of\nremembrance on high? The law of God written in this Bible condemns you;\nGod condemns you; you are condemned already for not believing in the name\nof God's only begotten Son, the Lord Jesus from heaven. Can you change\nthat condemnation by your feeble, fickle resolutions to reform? 'Can the\nEthiopian change his skin or the leopard his spots? then may ye also do\ngood that are accustomed to do evil.'\n\n\"Be assured also that it does not belong to you to change your own hearts.\n'Ye must be born again;' 'except a man be born again he cannot see the\nkingdom of God.' But that second birth comes not of blood, nor of the will\nof the flesh, nor of the will of man, but of God. 'Ye must be born again,\nbut ye must be born of the Spirit.' Notice that the word _saved_ is in the\npassive voice. Sinners do not save themselves; they must be saved by\nanother; they must be saved by one able to save, by one almighty to save,\nfrom the wrath of God and from sin, by one able to do for those who trust\nin him all that they need to have done in order to make their salvation\ncomplete and glorious. Christ is able to do this. The crucified and risen\nChrist is exalted a Prince and Saviour, to give repentance and remission\nof sins. The word of God says, 'To give,' and he rejoices to give.\n\n\"On one point we must pause and dwell with special clearness. Every\nanxious sinner must not only feel his guilty and lost condition, but he\nshould also thoroughly understand what he means when he asks what he must\ndo to be saved. He should see to it that he wants that salvation which\nJesus gives.\n\n\"In the Scriptures the sinner who would be saved is called upon to return\nto God. He has gone astray. He must retrace his steps. What is meant by\nthis? I mean that man's sin consisted at first and consists to-day in\nsaying, 'I will,' and 'I will not,' in opposition to the will and command\nof God. God said, 'Thou shalt not;' man said, 'I will.' God says, 'Thou\nshalt;' sinners say, 'I will not.' If a sinner is to be saved from sin,\nthis opposition must cease. When God says, 'Thou shalt not,' the sinner\nmust reply, 'I will not,' and when God says, 'Thou shalt,' the sinner must\nanswer, 'I will.' The sinner's 'will' and 'will not' must agree with God's\n'shall' and 'shall not.' In place of your self-will you must put God's\nwill; that is, repentance, a turning about, a returning to God. But\nremember, salvation, if it be real and thorough, is not submission for an\nhour, a day, or a year, but submission for ever and ever. It is submission\nwithout condition and without limits.\n\n\"The sinner says, 'This is a hard saying,' this utter and boundless denial\nof self-will and selfishness. But is it hard that the creature should\nyield to the Creator, that ignorance should yield to wisdom, that\nselfishness should yield to love, that sin should yield to holiness, that\npoor, lost, wretched, fallen man should yield to the eternal and\never-blessed God? It is only by yielding that his will is brought into\nsweet harmony with the will of God, and that he can be a sharer of the\ndivine blessedness.\n\n\"Your views on this point should be clear and distinct. If you wish only\nto be saved from the penalty of your sins, you do not desire the salvation\nwhich Jesus gives. He saves his people, not in their sins, but from their\nsins. If, however, you really wish for his full and glorious salvation,\nyou will desire that your will may be wholly subdued to the will of God.\nYou will be found ready to unite in the memorable prayer of the Lord\nJesus, 'Not my will but thine be done.' Salvation implies the giving up of\nself-will and a reverent submission to the will of God.\n\n\"Other sinful passions oppose the grace of God, but chiefly as helpers and\nsupporters of self-will. Pride and vanity strengthen self-will. Turbulent\nfleshly lusts urge on and back up self-will. Fear of man, fear of danger,\nand unbelief are but props of self-will. When 'my Lord Will-be-will'\nsubmits, the town of Mansoul returns to her rightful allegiance.\n\n\"The question at issue between God and the sinner, the question of\nself-will or submission, is often contested around the performance of some\nsingle definite duty. The Holy Spirit often presents to the convicted\nsinner's conscience some single duty and presses its performance. That\nduty is a test of the feelings and desires of the sinner's heart. So the\nSpirit understands it, so the sinner often understands it. As, in the\ngarden of Eden, God gave to Adam a test command, so does he now press upon\nthe conscience of convicted sinners test duties to show them what they\nare. That which is required may be important, exceedingly important, in\nand of itself, or it may be in itself of very little consequence, but in\nevery case the duty is all-important and its performance absolutely\nessential, because the Spirit has laid it upon the sinner's conscience. It\nwill show whether he wishes for salvation from sin or not.\n\n\"I used to hear a Christian relate an experience like this. While the\nSpirit of God was striving with him and conviction of sin was heavy upon\nhim, he felt a clear impression that he ought to go to his barn, and there\nat one certain place upon the hay-mow kneel and pray. His self-will rose\nin rebellion, chiefly, it would seem, because it was laid upon his\nconscience as a duty. But his distress grew upon him. He went to his barn\nand stood at another place and tried to pray, but no light or peace came;\nhis sense of his sins grew heavier. How could it be otherwise? He went to\nthe spot where he thought that he ought to go, and stood and prayed. Still\nno peace came, but increasing sense of sin. At length he thought, 'Why\nshould I not? Why not give up my own will? Why not pray that God's will\nmay be done?' He yielded, he kneeled at the place where he had thought he\nought to kneel, and there he first felt peace before God. This was a\nsingular experience. Perhaps a man more intelligent and better taught in\nthe Sacred Scriptures would never have such a thing pressed upon his\nconscience. But the battle of self-will is commonly fought around some\nsingle definite duty. That duty may be a confession of wrong done to a\nneighbor, or conversation with an impenitent associate, or a public\nconfession of sin before the great congregation. Whatever it may be, it\nshows the sinner his heart and leads him to decide to follow his own will\njust as he had always been accustomed to do, or it will lead him to pray\nearnestly that he may be enabled in everything to bow his will to the will\nof God. He will want the full salvation which Jesus in his grace brings\nmen--salvation from the penalty of sin and deliverance from its power.\n\n\"I draw no bow at a venture and speak not doubtfully when I say some of\nyou are standing face to face with duties pressed upon you by the Holy\nSpirit. Your self-will, supported by pride, and fear of man, and unbelief,\nand Satanic temptation, refuses to yield. The yoke of Christ seems to you\nlike bondage. The cross is supremely heavy. You draw back from it, and\nrefuse to bear it. I cannot take away the cross which the Spirit bids you\nbear. I dare not do it; I will not do it. As the messenger of Christ, I\nrepeat the voice of the Spirit and lay the duty, whatsoever it may be,\nupon your consciences. Do you really and honestly wish to be saved from\nsin? Then you will yield to the Spirit's kind and gracious movings; you\nwill yield humbly but heartily. If, however, you want something else than\nthe salvation which Jesus gives, what can you expect but perplexity,\ndifficulty, darkness? I beseech of you, deal truly and faithfully with\nyourselves on this point.\n\n\"To those who wish really to be saved I have good news to proclaim. There\nis a Saviour such as you need. Trust in Jesus as your Saviour. Place the\nwhole work of your salvation in his gracious hands. Christ saves sinners\njust such as you are. The faith which you are but to exercise is nothing\nelse than your confidence, by which you entrust yourselves to him. Faith\nhas no saving virtue in itself, but it is the hand by which the sinner\ntakes hold of Christ. With this duty few of you will have any great\ndifficulty. When once you wish to be saved from sin and are ready to\nsubmit to the will of Christ, you will have no reluctance to take him for\nyour Saviour. You believe that Christ is a divine Saviour. If saved at\nall, you expect to be saved by him who died on Calvary. Hardly for the\nworld would you resign your opportunity of coming to Christ and receiving\nhis grace. You believe that Jesus is the Christ, the Son of the living\nGod, the great sacrifice for sin. It remains that you should gladly accept\nwhat he offers and follow him as loving, trusting disciples.\n\n\"Follow the Spirit, and you will be led to Jesus and will come speedily to\nthe joy of salvation; resist the Spirit, and you grope in boundless\ndarkness and fall upon the dark mountains.\n\n\"In the Holy Scriptures the question of the text is asked and answered\nmany times. Hardly any two answers are alike. Are there different\nconditions and different duties required of different men? By no means.\nBut the Holy Spirit adapted the answer to the different spiritual states\nof the various inquirers. The answer is made to each questioner's heart. A\nself-righteous young man came to Jesus asking, 'Good Master, what good\nthing shall I do that I may inherit everlasting life?' Jesus answered,\n'Keep the commandments: thou shalt do no murder; thou shalt not commit\nadultery; thou shalt not steal; thou shalt not bear false witness; honor\nthy father and thy mother; and thou shalt love thy neighbor as thyself.'\nThe young man answered, 'All these have I kept from my youth up; what lack\nI yet?' Jesus said, 'If thou wilt be perfect, go sell that thou hast, and\ngive to the poor, and thou shalt have treasure in heaven, and come,\nfollow me.' The young man went away sorrowful. Jesus knew his\nself-righteousness, and gave him answers which opened that young man's\neyes to see himself. He gave him a test command, and the young man's\nrevulsion from that duty showed that, notwithstanding his self-confident\nclaim to righteousness, his riches filled all his heart. If your hearts\nare filled with the love of the world, you must put your possessions out\nof your hearts and follow Jesus.\n\n\"Nicodemus also came making the same inquiry. He must have asked something\nlike this, for Jesus answered such a question. 'Ye must be born again; ye\nmust be born of the Spirit,' said Jesus. Nicodemus was looking for a legal\nsalvation by outward formal services, but Christ gave him to understand\nthat salvation involves a great spiritual renovation wrought by the Holy\nSpirit, by which men old in sin become new creatures and enter the kingdom\nof God as little children. He taught him thus that salvation was only from\nGod. If any of you are looking for a cloak of self-righteous religious\nduties which you can put on, be assured that true religion springs from a\nwork of God wrought in the heart. You must be born again by the power of\nthe Holy Spirit. You must become new creatures in Christ Jesus.\n\n\"On the day of Pentecost the great company of men 'out of every country\nunder the whole heaven,' while listening to Peter's pungent address, cried\nout, 'Men and brethren, what shall we do?' 'Repent and be baptized, every\none of you, in the name of the Lord Jesus, for the remission of sins,'\nanswered Peter. Here were men who had a hand in crucifying Christ, or if\nthey had no active share in that deed of darkness, they had consented to\nhis death; they were partakers of the crime; very likely they had cried,\n'Crucify him, crucify him.' They saw their sin, and were pricked in the\nheart. Well might they repent of their rejection and crucifixion of their\npromised Saviour, the Son of God, from heaven. Others were devout men who\nhad come to Jerusalem to worship. Like Simeon they may have waited long\nfor the consolation of Israel. How easy for them to enroll themselves\namong the followers of Christ! All alike are commanded after repentance to\nput on Christ by baptism. That burial with Christ was the symbol of their\ndying and living again--of their dying unto sin and living again unto God.\nThe same duties are enjoined upon you. Repent of your long rejection of\nthe grace of God and his Son Jesus Christ, and before God and men devote\nyourselves to his service by a public confession of Christ in baptism.\n\n\"The jailer of Philippi was taken in the midst of his sins. He was holding\nthe servants of Christ in his dungeon. He knew for what offence they had\nbeen seized, and he made himself a partner in the crime of persecuting\nthem by the zest with which he thrust them into the inner prison and made\ntheir feet fast in the stocks. His conscience was ill at ease. Then came\nthe earthquake's shock, and he felt as if called to stand face to face\nwith his Judge. His soul was pierced through and through with a sense of\nguilt. 'What must I do to be saved?' he cried in the bitterness of his\nconviction. 'Believe on the Lord Jesus Christ, and thou shalt be saved,'\nanswered Paul. This is the answer to all of you who are well convicted of\nsin and have given up all self-righteous hopes. Christ saves you. Look to\nChrist, ask Christ; whosoever comes to him he will in no wise cast out.\nWill you not come to him? Will you not trust his promises and commit\nyourselves to his hands to be saved? He waits to bless you. He delights\nto be gracious. To save sinners he lived among men, and died and has\nascended. His hands are full of gifts. He comes to you, and stands and\nknocks at the door of your hearts. Will you bolt the door? There is joy in\nheaven over repenting sinners. This alone of all earthly transactions\ncarries joy to Christ and the angels. Accept of Christ, and earth and\nheaven will throb with a common joy.\"\n\nThese words were listened to with most earnest attention, for at that time\nChrist and heaven were realities in the minds of men, and salvation was a\nliving issue. Mr. Wilton spoke as an earnest man, without cant or\ncircumlocution, pressing upon men of thought and conscience the great\nconcerns of eternity. The full result of this discourse will be known only\nwhen the opening of the books at the last day shall reveal it, but the\nbeginning of the result was seen in the evening prayer-meeting. When the\ninvitation was given for anxious persons to make known their feelings,\nboth Ansel and Peter arose, and confessing in few words that the Spirit of\nGod had been striving with them, and that they had been resisting the\nSpirit, said that now they were determined to resist no more, and asked\nChristians to pray for them that they might be able to submit fully to the\nLord Jesus and trust entirely in him. Then there was a pause. Mr. Wilton\nwas just on the point of rising to close the meeting when Mr. Hume rose to\nhis feet. After a sudden start of surprise, a deep hush passed over the\ncongregation, and in the midst of deepest silence Mr. Hume said:\n\n\"I have been more than merely an impenitent man: I have been an\nunbeliever; I have been an infidel. I have not only tried to disbelieve\nthe Holy Scripture, but I have actually disbelieved. I have thought myself\nwiser than the word of God. I do not mean that I have enjoyed peace, that\nmy conscience has been at rest, and that I have been happy in my unbelief.\nThree months ago I began to grow more than usually discontented with\nmyself. Questions which I counted settled and put to rest for ever came\nback to trouble me. A hundred times a day the questions came, What if\nthere be a God who holds me responsible? What if there be a future life\nand a judgment day? What if Christ be the Son of God? Why such questions\nshould haunt me day and night I could not tell. I have learned to believe\nthat the Spirit of God was speaking to me. This restlessness brought me to\nthe church for half a day. If my object was to gain rest in unbelief, I\ncould not have done worse. My old arguments were unavailing to break the\nforce of the truths preached. The questions which had been sounding in my\nears and echoing in my heart began to change to solemn affirmations:\n'There is a God;' 'There is a day of judgment;' 'Appointed unto man once\nto die, and after that the judgment;' 'Christ is risen.' Texts of\nScripture learned in my boyhood and forgotten long years ago came back\nfresh to my memory. But I will not stop to rehearse to you all my\nstruggles of mind for two months past. For a few weeks you have seen me\nhere. I determined that I would try to find Christ if he manifests himself\nto men in these latter days. For two weeks I have tried to pray, but I\nhave found no satisfaction. Christ has not manifested himself. My darkness\nhas grown deeper and deeper. I have sometimes almost determined to abandon\nall thought of Christ and throw myself back again upon my former\nunbelief. But I could not lay down the subject.\n\n\"Since I began to try to pray I have felt, faintly at first, like the\nwhisper of a suggestion, but becoming clearer and stronger, like a voice\nfrom heaven, that I must in this congregation confess my former state and\nthe feelings which I have had. It seemed to me that I could not do this.\nIt seemed easier to die than to stand up here and confess that my belief,\nwhich I had pressed upon others and had boasted of as better than the\ngospel, had given me no peace. To-day I have been made to understand that\nthe Spirit of God has set me face to face with this confession. I have\nseen what it means to be saved--that my self-will must die or I must bid\nadieu to Christ and hope. I cannot live and die hopeless. I cannot rest my\nhead upon unbelief. I confess to you that all my thoughts have been wrong.\nMy beliefs and my unbelief have done me no good. My whole life has been\nenmity and opposition to the Holy Spirit. I will try to oppose the Spirit\nno more. I know not what the Spirit may lay upon me, I know not how soon I\nmay break my resolution, but I now feel that I want to be saved from sin,\nand cannot do otherwise than follow the Spirit though I dwell in darkness\nfor ever. If Christ reject me I cannot complain, but if you think there is\nhope for one who has so despised the grace of God, I entreat you to pray\nfor me.\"\n\nIt is needless to say that from scores of family altars and closets\nsupplications went up to God that night for the salvation of Mr. Hume and\nAnsel and Peter, and men prayed especially that Mr. Hume, who for years\nhad been such a tower of strength to the ungodly and the dread of\nChristians, might be saved for the glory of Christ and the confounding of\nunbelievers. Those prayers were heard. When the report of that meeting and\nthat confession went out through the community, unbelievers were silent.\nIt was as if the God of battles had emptied his quiver into the hearts of\nhis enemies.\n\n\n\n\nCHAPTER XII.\n\nTRANSFER OF HEAT IN SPACE.\n\n\n\"We now turn our attention,\" said Mr. Wilton, \"to a new theme. In the\nvicissitudes of day and night and of summer and winter heat is transferred\n_in time_. We now are to look at the arrangements by which heat is\ntransferred _in space_. But since the transfer of heat in space requires\nmore or less of time, the means employed are such as suffice to accomplish\nboth objects. Heat is treasured up and carried away to distant regions,\nand delivered up for use as occasion demands.\n\n\"In a previous lesson the inclination of the earth's axis was spoken of.\nBy this means the northern hemisphere of the earth is turned somewhat\ntoward the sun during one half of the year, and receives a correspondingly\nlarger portion of heat, while during the other half of the year the\nsouthern hemisphere is turned toward the sun and is warmed. This\ninclination of the earth's axis to the plane of its orbit gives us the\nchange of seasons.\n\n\"The change of seasons is manifestly designed for the welfare of man.\nAlong with the genial warmth of summer, fruits and grains and the comforts\nof life are carried far toward the poles, into regions which otherwise\nwould be desolate with perpetual frost. But these extremes need to be\nsoftened; otherwise, the violence of the changes would prove destructive\nrather than beneficent. The severity of these annual changes of\ntemperature is ameliorated by some of the grandest movements and\narrangements upon our globe. These arrangements we have in a very\nimperfect way already examined.\n\n\"But there are other inequalities of temperature besides those of day and\nnight, summer and winter. Passing from the equator toward the poles, every\ndegree of the earth's surface passed over causes the sun to sink one\ndegree from the zenith toward the horizon, and gives a corresponding lower\ntemperature, till within the polar circles for a part of the year the sun\nis entirely hidden and winter reigns without a rival. The temperature of\nthe sea differs from the temperature of the land; the sun comes nearer to\none hemisphere than the other, and remains longer north of the equator\nthan south. These and many other differences upon the earth give to\ndifferent parts of the world every possible variety of temperature and\nclimate. These differences of temperature upon sea and land, from zone to\nzone and from hemisphere to hemisphere, are equalized or ameliorated by\nmany agencies, but chiefly by a transfer of heat in space, a transfer of\nheat from place to place.\n\n\"I do not need to tell you that while we in the northern hemisphere are\nenjoying the warmth of summer the southern hemisphere is enduring the\nseverities of winter, and in turn, when winter comes to us, summer smiles\nupon the nations that live south of the equator. You also remember that\nthe orbit of the earth is not an exact circle, but an ellipse, that is,\nwhat is sometimes called in common language a long circle. For this reason\nthe earth is three millions of miles nearer the sun in one part of its\norbit than when in another part. Can you tell us, Peter, at what season of\nyear the earth is nearer the sun?\"\n\n\"In midwinter, or about the first of January. I have always remembered it\nbecause it seemed so strange to me, when I learned it, that the sun should\nbe nearest the earth at the coldest season of the year.\"\n\n\"Yes, one is reminded by it of the humorous argument that the sun must\nemit cold instead of heat, because when we are at the point of the earth's\norbit which is nearest the sun it is winter, and the higher one ascends\nupon mountains toward the sun, the colder he finds it. But this nearness\nof the sun while south of the equator would naturally give the southern\nhemisphere a warmer summer than the northern. For this there is a\nbeautiful compensation. The earth passes through her orbit more rapidly\nwhen nearer the sun, and that half of her orbit is also smaller, so that,\nas the result of this, the sun remains north of the equator about eight\ndays longer than in the southern hemisphere. The sun is nearer while in\nthe southern hemisphere, but the summer is shorter. That which the\nsouthern hemisphere gains in distance it loses in time, and that which the\nnorthern loses in distance it gains in time.\n\n\"The nearness of the sun while south of the equator, the shortness of the\nsummer, and the corresponding distance of the sun and length of the\nwinter would tend to give the southern hemisphere great extremes of heat\nand cold, a short and hot summer and a long and cold winter. For this also\nthere is a most interesting compensation in the comparative amount of land\nand water north and south of the equator. Much more than one-half of the\ndry land lies in the northern hemisphere. This would tend to give the\nnorthern hemisphere extremes of heat and cold. South of the equator there\nis comparatively little land and much water, which tends to give the\nsouthern hemisphere evenness of temperature. The inequalities of the\nearth's orbit and the earth's motion in its orbit we find counterbalanced\nby the arrangement of land and water upon the earth's surface.\n\n\"In connection with this we may notice still another compensation in the\nelevation of the lands by which the burning heat of the torrid zone and\nthe rigors of the colder zones are more or less diminished. The greater\nthe elevation of any region of country, the cooler must be its climate.\nPhysical geographers like Baron von Humboldt and Guyot have made\ncalculations which show that those grand divisions of the earth which lie\nin the hot regions of the earth are most elevated above the sea level.\nSouth America lies higher than North America, Asia is more elevated than\nEurope, and Africa is more elevated than Asia. The continents rise as they\napproach the equator and sink toward the sea level as they come nearer the\npoles. As these colder lands approach the water level their valleys sink\nbeneath the sea, their coast lines become deeply indented with bays and\ngulfs, and lakes abound. Thus the warmer waters of the sea are\ninterspersed among the cooler lands, and the temperature of the lands is\nraised. The very elevation of the continents and the configuration of the\nlands have a providential relation to the temperature and climate of the\nworld. We cannot suppose that arrangements like these, so aptly fitted to\nthe needs of man, came by chance. In the unmeasured ages past, while this\nearth was in preparation for man, God had the beneficent _end_ in view;\nnay, in the very beginning, the whole plan and its beautiful completion\nwas had clearly in mind. Millions of ages ago the great Creator tenderly\nconsidered the comfort and well-being of the human race, the latest born\nof his creatures, in these last ages.\n\n\"As a general statement, the torrid zone receives an excess of heat, while\nthe frigid zones receive too little, and the temperate zones, lying\nbetween, receive, at different times and places, sometimes too little and\nsometimes too much. The providential arrangements for equalizing\ntemperature are, then, chiefly arrangements for conveying heat from the\noverheated tropical regions and scattering it over the temperate and polar\nregions. First among these means we will notice the _trade-winds_, or, as\nfor the sake of brevity they are often called, 'the trades.' Will you tell\nus, Samuel, how winds are caused?\"\n\n\"The air is heated at some place and expands; it becomes lighter and\nrises, while the colder air around rushes in to fill its place.\"\n\n\"You use the words which are commonly employed in explaining the origin of\nwinds, and very likely your idea is right, but the language needs a little\ncorrection. The warm air does not rise of its own accord, so to speak, but\nis pressed upward. The warm air is expanded; it presses outward and\nupward; the same weight of warm air occupies more space than cold air;\nthe warm air rises and overtops the surrounding air, and then flows off in\norder to reach the common level. The column of warm air is lighter than\nthe cooler air, and cannot balance it; consequently, the cold air sinks\ndown, pressing the warm air upward. In this manner an ascending current of\nwarm air is formed, and also currents of cold air flowing from every\ndirection toward the warm centre. These currents continue until the\ntemperature of the air is equalized.\n\n\"The atmosphere is commonly believed to be forty-five or fifty miles in\nheight, though some men have estimated its height as very much less than\nthis, while others believe it to be six or seven hundred miles in height.\nAre we to suppose that the column of heated air reaches to the top of the\natmosphere?\"\n\n\"I think not,\" answered Mr. Hume. \"The rarefaction of the lower part of\nthe column renders the whole column lighter than the air around, and the\nwarm air, as we know by the movements of the clouds, after rising a little\nway, spreads off in every direction, forming upper currents corresponding\nto the currents below, but moving in the opposite direction.\"\n\n\"Only a few days ago,\" remarked Peter, \"I saw in the same part of the sky\nclouds moving in exactly opposite directions, and others which seemed to\nbe standing still. I knew how one layer of clouds might be moving north\nand another layer moving south, but I did not understand why some should\nbe standing still.\"\n\n\"Do you imagine, Peter, that the upper and lower currents of air, moving\nin opposite directions, come sharply together, the one sliding against the\nother?\"\n\n\"I think not,\" said Peter.\n\n\"Supposing, then, as is certainly true, that a stratum of still air lies\nbetween the upper and lower winds, does not that explain how certain\nclouds might be standing still while the others were moving?\"\n\n\"I might have thought of that myself.\"\n\n\"But how does this carry heat from the warmer region to the colder regions\naround?\" asked Ansel. \"I see how the colder air coming in would cool the\nwarm region, and how the warm ascending air would carry away the excess of\nheat, but how do the cooler regions get the advantage of this heat?\"\n\n\"That is just what I was on the point of explaining. Do you remember what\nwas said about the production of cold by expansion and of heat by\ncompression?\"\n\n\"I remember that if air be rarefied by removing pressure from it, its\ntemperature falls: I think you said that a part of its sensible heat\nbecomes latent; and if air be compressed, its temperature rises. I have\nseen experiments with the air pump and condenser to prove this.\"\n\n\"That principle explains the transfer of heat by winds. If the heated air\nrose to the upper regions, and there radiated its heat, nothing would be\ngained; the heat would be simply radiated into space. But as the warm air\nrises pressure is more and more removed from it; it expands; its sensible\nheat becomes latent and is thus kept from radiation; its temperature\nfalls, but not from loss of heat. This rarefied air forms the upper\ncurrent flowing away from the heated centre. In due time this air must\ncome to the surface of the earth again. Whenever this takes place the air\nis brought again under pressure; it is compressed, and its latent heat\nbecomes again sensible. Heat is thus transferred from the warmer region to\nthe colder in a latent condition, so that it cannot be lost. We must now\napply this to the trade-winds. What are the trade-winds, Mr. Hume?\"\n\n\"They are regular winds blowing from a little north and south of the\ntropics of Cancer and Capricorn south-west and north-west toward the\nequator.\"\n\n\"These winds are called _trade-winds_,\" continued Mr. Wilton, \"on account\nof their great advantage to trade or commerce. The regular and steady\nsweep of these winds bears the merchantmen rapidly and safely on their\nway. The formation of 'the trades' is easily explained. By the intense\nheat of the sun under the equator the air is greatly expanded and\nrarefied; the heated air rises along the whole line of the equator; from\nboth sides the cooler air presses in, is heated, and rises; thus steady\nwinds are formed from the tropics, or a little beyond the tropics, toward\nthe equator. If the earth had no rotation upon its axis, these winds would\nblow directly toward the equator, exactly south and north. The rotation of\nthe earth gives the trade-winds their oblique, south-west and north-west\ndirection. Suppose that a single particle of air at the tropic of Cancer\nstarts upon its journey toward the equator. At its starting it has the\nsame motion eastward as the surface of the earth at that place, that is,\nabout nine hundred and fifty miles per hour. But as it moves on southward\nthe degrees of longitude become longer and the motion of the earth's\nsurface becomes more rapid, till at the equator its motion is one thousand\nand forty miles per hour. But the particle of air we are watching is not\nfastened to the earth's surface, and as the earth moves more rapidly the\nnearer we come to the equator, the particle of air falls behind, that is,\nthe air moves southward and eastward, but the earth moves eastward more\nrapidly than the air, so that the air falls behind and seems to be moving\nwestward. The result is that the air upon the earth's surface moves\nsouth-west. That which takes place with a single particle takes place with\nthe whole body of the air, and that which takes place north of the equator\ntakes place south of it also, producing north-west winds. On reaching the\nequator the winds from the north and the south meet and stop, forming the\nequatorial calms, and mingling together, they rise into the higher\nregions. In rising, the air bears away heat from the torrid zone, and this\nheat, rendered latent by the expansion of the air, is carried north and\nsouth by the upper currents as far as the limits of 'the trades.' In due\ntime these upper currents descend and their latent becomes sensible heat,\nand is used in raising the temperature. Mr. Hume, can you suggest any\nmethod by which we can estimate the amount of heat which is carried north\nand south by the return trades?\"\n\n\"I know of no method, except to estimate the amount of heat necessary to\nraise that flood of air which pours in from the temperate zones to the\nequatorial heat. That immense amount of heat must, nearly all of it, be\ncarried away to the temperate regions.\"\n\n\"This is the general explanation of the trade-winds. You must understand,\nhowever, that, in certain regions and under certain conditions, the trades\nare liable to interruption or change of direction. Desert regions within\nor near the tropics give rise to local winds which overpower the trades.\nIn Southern Asia, while the sun is north of the equator, the land becomes\nso much hotter than the sea under the equator that the trade-wind is\noverpowered and reversed, forming a wind which blows to the north-east\ninstead of the south-west. But this is only a beautiful flexure, so to\nspeak, of a general arrangement for the greater advantage of a particular\nregion. By this means the summer winds of Southern Asia come from the sea.\nNorthern winds would have been dry. Prevailing northern winds would have\nmade the whole of Southern Asia a desert; but the south-west monsoons come\nfrom the Indian Ocean laden with vapor, and render Southern Asia a very\ngarden for fertility.\n\n\"The next great agency for equalizing temperature between the torrid and\ntemperature zones is the formation and condensation of vapor. This comes\nin here, because it depends for its efficiency upon the agency of winds.\nMore than once this method of conveying heat from place to place has been\nhinted at, but deferred till we came to the proper place to speak of\nwinds.\n\n\"The trade-winds, passing over from a colder to a warmer climate, are\nconstantly accumulating vapor. Under the equator the annual evaporation\nfrom the surface of the ocean is set down at fifteen feet, or half an inch\ndaily. The formation of this vapor consumes heat which would boil more\nthan eighty feet of ice water. The vapor thus formed is borne upward by\nthe ascending current of heated air. On reaching the higher regions a\nportion of it is condensed and forms a belt of clouds around the earth.\nThis belt of clouds along the equator is known as the 'cloud-ring.' This\ncloud-ring shields the belt of calms from the burning rays of the sun and\nsends down almost incessant rains. But does not that condensation which\nforms the cloud-ring set free latent heat, and thus intensify the great\nheat of the equator? Latent heat becomes sensible, but it is given out\ninto the ascending current of air, and serves only to give it another lift\ntill by expansion of the air it again becomes latent. The heat is simply\ntransferred from the vapor to the air. The vapor which remains uncondensed\nis borne away on the wings of the return 'trades' to the south and to the\nnorth, and in due time is condensed and returns to the earth as rain; the\nheat which is given out by its condensation, wherever and whenever it is\ncondensed, is given over as latent heat to the keeping of the air, and is\npassed back for use whenever the air descends to the earth.\n\n\"Vapor gathered from sea or land is everywhere exerting this equalizing\ninfluence upon temperature. Does the temperature rise in any place? Vapor\nis formed. Every moist body begins to give up its moisture, and the excess\nof heat is employed in turning this water into vapor. This is the method\nby which perspiration cools man or beast; whether it be insensible\nperspiration from the invisible pores of the skin, or perspiration\nstanding in beady drops upon the face of the toiling laborer, vapor is\nformed and heat is carried away. Have you not noticed on close, muggy days\nwhen nothing dries, showing that very little vapor is forming, that\nperspiration seems to have no cooling effect? It oozes from the skin, but\ndoes not evaporate, and hence does not carry off the surplus heat. Animals\nlike dogs and oxen, that do not become wet with perspiration, do not bear\nheat well; they soon pant and loll, attempting to get rid of the excessive\nheat through the moist breath and open mouth.\n\n\"The sum-total of heat transferred by this agency is too great for\ncomprehension. Look at the Amazon rolling to the ocean a flood broad as an\narm of the sea. That great river is brought from the Atlantic Ocean on the\nshoulders of the trade-wind. As the vapor is slowly lifted by the rise of\nthe land from the sea level to the summits of the Andes, it is condensed,\nand falls as rain. Well is it for South America that the Andes were thrown\nup on the western coast, for the winds west of the mountains are dry as a\npressed sponge, and the most of that narrow slope is barren and desolate.\nSouth America would be a desert if the Andes ran along the eastern coast.\nLook at the Mississippi, and the great rivers of Europe, and the matchless\nrivers of Southern Asia. All the rivers of the world represent only the\n_wastage_ of the rain which falls upon the land after supplying the wants\nof the vegetable kingdom and keeping the lands moist. All this water is\nlifted into the air by heat, and every movement of vapor is a movement of\nheat. Every particle of vapor goes freighted with heat. Every cloud driven\nacross the sky represents the transfer of heat, and every transfer is in\nthe direction of equalization. Everywhere the tendency is to equilibrium.\nNature has no processes for transferring heat from colder to warmer\nregions.\n\n\"We may form a conception of the amount of heat transferred by the agency\nof vapor by estimating the amount of heat-force required to evaporate the\nwater which forms our rain-clouds and lift them into the upper regions.\nAccording to a calculation of Mr. Allen, late of Providence, to evaporate\none-eighth of an inch of water daily from that belt of the surface of the\nearth lying within the tropics, and raise it five thousand feet high,\nrequires 4,700,000,000 horse-power, or one hundred and thirty times the\neffective force of the whole human race, reckoning it at 250,000,000\nable-bodied men. But the actual evaporation from the sea within the\ntropics is believed to be about half an inch daily--four times as great as\nMr. Allen's supposition.\n\n\"I see, however, that our time is nearly exhausted, and I wish before\nclosing to revert to that more important theme upon which I spoke this\nforenoon. I do not know how the truths preached interested or affected\nyou, nor do I now wish to have you tell me. I wish only to say that, as\nthe sermon was preached at your request, I hope it proved applicable to\nyou, and that you will give the truths presented earnest attention.\nConsider them well, and make your conclusions known this evening.\"\n\nThe conclusion which the evening made known, you, reader, have already\nlearned.\n\n\n\n\nCHAPTER XIII.\n\nOCEAN CURRENTS AND ICEBERGS.\n\n\nA week has passed since Mr. Hume made his frank confession. He went home\nno lighter of heart than before, yet he felt in some respects different,\nfor he had attempted to do what was right in the sight of God. But he did\nnot feel the joy of sins forgiven. He had not looked upon Christ as a\nSaviour for himself. He felt that God had distinctly set life and death\nbefore him. His doubts were gone; the spiritual world was a reality;\nChrist stood at his right hand and Satan at his left; he stood where the\npath of destiny divided, the one path leading up to heavenly seats with\nChrist, the other leading down to darkness and despair. A voice seemed to\nbe whispering in his ears, \"This is the last call.\" He went to his chamber\ndetermined, if possible, to settle the question of life or death before\nhe left the place and before he slept. He took his Bible, and on his knees\nturned and read the Psalms at random. But the cloud of darkness only\ngathered deeper. The words of David's penitential Psalm caught his eye:\n\"Against thee, thee only, have I sinned, and done this evil in thy sight.\"\nHe felt that these words of David were true in his case also. All his long\nimpenitence and bold unbelief had been against God. By night and by day,\nfor many a long year, before the sleepless eye of God, he had lifted up\nhis hand, almost defying the holy One, yet the lightning of God had not\nsmitten him. He wondered as much at the long-suffering of God as at his\nown dreadful daring of the divine wrath. He had been taught better things;\nhe was trained to know the Scriptures and to go reverently to the house of\nGod, but he had turned from Christ and hope. He read on: \"Deliver me from\nblood-guiltiness, O God, thou God of my salvation.\" He felt that this\nbelonged to himself more than to David. David had shed the blood of\nnatural life, but he had destroyed the souls of men. He had stood chief\namong unbelievers. He had led young men into infidelity. He had seen them\ndrink in his unbelief like water, throw off all restraint, and rush\nheadlong to ruin. He had wrought a work of evil which he could never undo,\nand for which he could make no atonement. What was a confession in\ncomparison with the ruin he had caused? What could his confession do for\nthe young men already, perhaps, among the lost through his influence?\nCould his late repentance call them back to life and hope? Would God\nforgive and raise to heavenly heights a man who had dragged others down to\nhell? Would it be possible that Christ should fill his soul with\nblessedness while his victims were drinking the wine of the wrath of God?\nA deep horror seized him. The darkness of eternal death seemed to enfold\nhim. Must he, then, after having caught a glimpse of life and joy, be cut\noff from hope and be driven from God for ever? This would be just, but he\nfelt that he could not endure it. \"O thou great and holy God,\" he prayed,\n\"I will ascribe righteousness to thee though thy righteous wrath shall\nsink me to hell; but, O thou merciful God, my soul cannot endure thy\njustice. The foretaste of thy wrath fills me with the pangs of eternal\ndeath. O God, have mercy upon me. O God, blot out my transgressions.\nCreate in me a clean heart, and renew a right spirit within me. O Christ,\nwhom I have despised, cast me not from thy presence. Help me to submit to\nthee. Help me to follow thee. Spare me that I may undo something of that\nwhich I have done against thy glory and the souls of men. O Jesus, I can\ndo nothing to save myself. O Lord, have mercy on me, the chief of\nsinners.\"\n\nHe read the invitations and promises of Christ, and prayed again. Again he\nread and again he prayed. Little by little the promises of Christ stirred\na feeble faith in his heart; he felt that there was still hope for him,\nand with the determination to cast himself upon the sure mercies of Christ\nand to devote himself to his service, he threw himself upon his bed, and\nbeing wearied almost to exhaustion, soon fell asleep. When he awoke it was\nbroad daylight. He had slept a sweet, refreshing sleep. But he was\nrefreshed not merely in body. He woke to a new world. His heart was filled\nwith sweet thankfulness. \"How beautiful,\" he said, \"is God's world! I\nnever saw it so before, but the earth and sky seem clothed in glory. But\nmost wonderful of all is God's goodness to me. I have rebelled against him\nall my life, yet he has loved me and sought for my salvation, and now the\nsunlight of his love has broken through the thick clouds of my sin, and a\nday of hope and joy has dawned upon my life. Christ has indeed revealed\nhimself. Blessed be his holy name for ever and ever! What shall I render\nunto the Lord for all his benefits? I will take the cup of salvation and\ncall upon the name of the Lord. I will pay my vows now in presence of all\nhis people. I will teach transgressors thy ways, and sinners shall be\nconverted unto thee.\"\n\nAll this was known to the people, for during the week Mr. Hume had spoken\nof it in private and in public. He had told it to Mr. Wilton, and they had\nrejoiced together.\n\nAnsel and Peter had also regularly presented themselves at every meeting\nas anxious inquirers desiring the grace of God. Peter had also on his\nknees said from the heart, \"Here, Lord, I give myself away,\" and had\nreceived the assurance that his sins were forgiven. The Spirit of God\nwitnessed with his spirit that he was born of God. He began at once to\nuse all his influence to bring his young friends to Jesus. The addition of\ntwo such workers as Mr. Hume and Peter, each moving in his own circle of\nacquaintances, gave a fresh impulse to the religious interest, which was\nnow becoming deep and pervasive. Especially had Mr. Hume's conversion, so\nclear and positive, confounded those who had sat \"in the seat of the\nscornful,\" and many came in now for the first time to see for themselves\nwhat it could be that had mastered their cold, clear-headed leader in\nunbelief.\n\nBut Ansel still walked in darkness. He had talked with Mr. Wilton, but no\nlight had entered his mind. He said that he thought he had submitted in\nall things to the will of God. He was becoming impatient that Christ had\nnot come to him as to others. This was their condition as they came\ntogether upon the Lord's Day. They all understood each other, and had no\nneed now to ask questions or make explanations. Mr. Wilton believed that\nthe study of God's works would not interrupt the working of the Holy\nSpirit, and therefore went on with his lesson as usual.\n\n\"We have already spoken of the transfer of heat from the torrid to the\ntemperate and frigid zones by the agency of winds and watery vapor. These\ncarry heat chiefly in a latent condition. But great movements of heat take\nplace in a sensible state. In this transfer of heat, also, water is the\ngreat carrier. The winds and vapor go freighted with latent heat above,\nand the waters and wind go freighted with sensible heat below. We will\nfirst examine the operation of the ocean currents.\n\n\"Not only do rivers run through the lands and hasten to the sea, but in\nthe midst of the oceans rivers are flowing in comparison with which the\nMississippi, the Amazon, and the Yang-tse-kiang are rippling brooklets.\nThe earth is belted by these ocean streams traversing the seas. An ocean\ncurrent, called the Gulf Stream, issues from the Gulf of Mexico between\nthe Florida coast and the Bahama islands. It flows northward off the coast\nof the United States, gradually increasing in breadth and spreading over\nthe Atlantic Ocean. It is deflected by the New England coast and the great\nshoals off Newfoundland, called the Grand Banks, or else by another\ncurrent flowing southward from Baffin's Bay, and strikes across the North\nAtlantic, bathing the shores of the British islands and reaching even to\nIceland.\n\n\"The general outline of the ocean currents is this: issuing from the South\nPacific, a current flowing eastward splits upon Cape Horn. The western\nportion, called Humboldt's current, flows northward along the western\ncoast of South America, and is swallowed up and lost in the great\nequatorial current of the Pacific. This is a broad current flowing\nwestward and covering the entire space between the tropics. Striking upon\nthe eastern shores of Asia, this equatorial current divides, one part\nflowing northward along the coast of Asia, the other finding its way\nthrough the many islands, sweeping across the Indian Ocean, and flowing\ndown the eastern shore of Africa on each side of Madagascar. Doubling the\nCape of Good Hope, the current continues in a north-westerly direction\nacross the Atlantic. Striking upon Cape St. Roque, this current again\ndivides; a part flows south and a part pours into the Caribbean Sea. From\nthe Caribbean Sea it issues as the Gulf Stream, of which I have already\nspoken. This Gulf Stream impinges upon the western coast of Europe, and\npours partly into the North Sea and partly flows south off the western\ncoast of Africa, completing thus the circuit of the Atlantic. The currents\nof the Indian and of the great Southern Oceans are as yet very imperfectly\nunderstood. Of all the ocean streams the Gulf Stream is most famous and\nbest understood. I shall therefore use this as an illustration of the\nagency of ocean currents in conveying heat and modifying climate.\n\n\"The waters of the Caribbean Sea are heated by the tropic sun to\neighty-eight degrees. From these heated waters the Gulf Stream issues\nsalter and warmer, and of a deeper blue, than the waters of the\nsurrounding sea. Its greatest velocity as it issues from the gulf is a\nlittle more than three miles per hour. As it flows northward its velocity\ndiminishes, its breadth becomes greater, and its depth less. It covers\nthus with its warm waters a broad belt of the Atlantic Ocean, and extends\nits influence to the most northern part of Europe. You can judge of the\namount of heat which is removed from the tropics when I tell you that the\nunmeasured flood of the Gulf Stream would swallow up three thousand rivers\nlike the Mississippi. This one ocean stream is many times greater than\nall the rivers of the world. We feel the warmth of the Gulf Stream with\nevery wind that blows from the sea. To this the British isles owe their\nmild, moist climate and perennial greenness, and by its influence a winter\nin Iceland, upon the Arctic circle, is no more rigorous than a winter in\nMontreal, twenty-one degrees nearer the equator. But what is the Gulf\nStream, though it be fifty fold greater than all the rivers of the world,\nin comparison with the whole sum of the ocean streams? Upper currents and\nunder currents fill the sea. They meet the explorers of the sea\neverywhere. The navigator drops his measuring line, and finds it swept\naway and drawn out by unseen currents. All these movements of the waters\nare in favor of the equalization of temperature. The cooler waters of the\nfrigid and temperate zones are mingled with the heated waters of the\ntropics and exchanged for the equatorial waters. The transfer of heat\nwould not be greater if broad rivers of molten lava were flowing from the\nequator to the poles.\n\n\"Another agency for the transfer of heat is the movement of ice, and\nespecially of icebergs.\"\n\n\"Will you not tell us,\" said Samuel, \"how these ocean currents are\nproduced? I can understand how winds are formed, but I do not see that\nthese streams in the sea could be formed in the same way.\"\n\n\"I designed to speak of this, but for the moment it had slipped from my\nmind: I am glad that you called my attention to it. I do not expect,\nhowever, to give a full and satisfactory account of their origin. If I\nshould do this, I should succeed where every other man has failed. I shall\nnot attempt a full explanation. By some means or other, the waters of the\nocean are thrown out of equilibrium, and these currents are plainly an\neffort to restore the balance or equilibrium of the waters. Many\ninfluences and agencies conspire to disturb the equilibrium of the sea.\nThe attractions of the sun and moon are constantly counteracting the\nattraction of the earth and lifting the waters, so to speak, above their\nnatural level. The tides produced by these attractions of the sun and moon\nare the immediate cause of some of the minor local currents. The winds set\nthe waters in motion, tending to pile them up in one place and leave the\nsea below its natural level at another. The effect of strong winds in\npiling up the waters, even upon our great lakes, is very considerable. A\nheavy east wind upon Lake Erie has been known to drive the waters toward\nthe western end of the lake so much as to leave Niagara River above the\nfalls almost dry. On the other hand, a heavy west wind drives the waters\neastward, and produces almost a flood in the river. The influence of\nconstant winds like the 'trades' acting upon an immense expanse of water\nmust be very much greater. Unequal evaporation tends to destroy the\nbalance of the waters. In the colder regions the evaporation is very\nlittle, while within the tropics it amounts to about half an inch daily,\nor fifteen feet per annum. The head of the Red Sea is two feet lower than\nits mouth on account of evaporation. This unequal evaporation causes also\nan unequal saltness, and consequently an unequal weight. The fresher and\nlighter water cannot balance an equal bulk of salter and heavier water.\nWhen once currents are started the revolution of the earth upon its axis\nwould affect them, just as the rotation of the earth affects the\ntrade-winds. Now, all these various agencies, and perhaps many others,\ncombine their influence to destroy the equilibrium of the waters of the\nocean. They unite and interweave their influence in a thousand ways beyond\nall human calculation. The result is the ocean currents. But how much is\ndue to one cause and how much to another in the present state of knowledge\nno man can tell. Only for a few years have the phenomena of ocean currents\nbeen made the object of scientific observation and research. But the\neffect of ocean currents in modifying climate is well understood, and the\nmodification of climate means nothing else than the transfer of heat. This\nis all that I have to say of the rivers of the sea, and if there are no\nmore questions, we will now look at the movement of heat caused by\nicebergs.\"\n\nNo question was asked, and Mr. Wilton continued:\n\n\"In polar regions there must be an immense formation of ice. Except in the\noceans, the movements of water are chiefly movements of water in the\ncondition of ice. Only for a small part of the year could water exist\nunfrozen. Immense regions of the Antarctic continent seem to be covered\nwith one broad glacier. The ice pushes down into the sea until,\nundermined by the dashing of the waves, it breaks off, and enormous\nfragments are launched upon the deep waters. Sir James Ross saw in the\nsouthern ocean a chain of such icebergs extending as far as the eye could\nreach from the mast-head, many of them from one hundred feet to one\nhundred and eighty feet in height and miles across. Captain d'Urville saw\none thirteen miles long and one hundred feet high. Its bulk was so vast\nthat though the waves were dashing against it not a tremor was\nperceptible. Astronomic observations could be made from it as if it were\nsolid rock rooted in the heart of the earth. In the same manner icebergs\nare formed in the northern ocean also. How much heat is given out in the\nfreezing of water?\"\n\n\"About one hundred and forty degrees,\" answered Peter.\n\n\"In the formation of icebergs, then, heat is given out nearly sufficient\nto boil an equal quantity of cold water. The icebergs float away toward\nthe equator. They come down from Baffin's Bay till they meet the Gulf\nStream off Newfoundland. In the southern hemisphere they come ten degrees\nnearer the equator. As they float toward the tropics they slowly melt, and\nin their melting they exact from the air and the sea where they melt the\nsame amount of heat which they gave up in their freezing. If they melted\nat the same place where they froze, there would be no transfer of heat.\nBut they are formed in the polar regions; they give out their heat in the\nfrigid zone, while they melt and absorb a like amount of heat from the\ntemperate zones. In this manner the polar regions are exchanging with the\ntemperate zones ice for water. They borrow water, rob it of its latent\nheat, and send it back in the form of ice. The temperate zones supply the\nneeded heat and bring the ice back to the form of water, when the polar\nregions again borrow it, seize upon its heat, and again send it back in\nthe form of ice mountains. The effect is the same as if thousands of\nrailroad trains were transporting water to the frigid zones, leaving it\nthere to freeze and give up its one hundred and forty degrees of latent\nheat, and bringing it back in the form of ice. Let us estimate the bulk of\none such iceberg as that seen by Captain d'Urville. It was thirteen miles\nlong and one hundred feet high, and we will suppose that it was four miles\nbroad. Standing out from the water one hundred feet, it must have sunk at\nleast eight hundred feet below the surface. This would give us the\nenormous bulk of (1,304,709,120,000) one trillion three hundred and four\nbillions seven hundred and nine millions one hundred and twenty thousand\ncubic feet of ice. The burning of one pound of coal will generate heat\nsufficient to melt about five and a half cubic feet of ice. To melt one\nsuch iceberg would require more than one hundred and eighteen millions of\ntons of anthracite coal. This is the amount of heat given out in the polar\nregion by its freezing. This is the amount of heat transported from the\nwarmer to the colder regions. But what is one iceberg to the thousands\nwhich drift yearly from the frigid zones toward the tropics?\n\n\"But even this hardly represents the entire transfer of heat by the agency\nof icebergs. The icebergs are formed from the snows of polar storms, and\nthese are formed from the condensation and freezing of vapors. In the\nprocess of condensation one thousand degrees of heat are given out. Every\niceberg _represents_ a transfer of heat sufficient to boil more than six\ntimes its weight of ice water.\n\n\"One marked illustration of the effect of icebergs we ought to notice.\nDown through Baffin's Bay icebergs are constantly floating. They are borne\non southward till, in the still waters of the Grand Banks, between the\npolar current and the Gulf Stream, they float around and melt and\ndisappear. To these melting icebergs the chilliness and unfailing fogs of\nthe Grand Banks are due; and not only this, but the very existence of the\nBanks is supposed to be due to the deposit of sediment, sand, earth, and\nstone brought by polar ice.\n\n\"I have spoken only of the polar glaciers and the icebergs formed by their\npushing off into the sea. But the same transfer of heat is taking place,\non a very much smaller scale and within narrow limits, by the glaciers of\nthe Alps and every other mountain glacier. The glaciers are nothing else\nthan rivers of ice. Snow falls upon the mountain tops and valleys of the\nmountain sides from age to age. The snow slowly changes to the structure\nof ice, and by its enormous weight flows down through the gorges of the\nmountain sides, till in the warmer vales below it melts and disappears.\nWe have not time to go into a full examination of all the interesting\nphenomena of glaciers, but this one point you will notice and remember:\nthese rivers of ice--for they flow like rivers--cool the valleys and tend\nto warm the mountain tops; of course upon the tops of the mountains there\ncan be no accumulation of heat, because, standing out into the eternal\ncoldness of space, and swept by winds for ever, and exposed by the\nthinness of the air to a rapidity of evaporation unknown at the sea level,\nheat is caught up and borne away in a moment.\n\n\n[Illustration: TRANSPORTATION of HEAT.\n\nPage 288.]\n\n\n\"This closes this department of our theme. I might have gone much more\ninto details and given you great stores of particular facts and figures,\nbut they would have added nothing to your understanding of the subject,\nand we can hardly afford to devote our Lord's Day to mastering the details\nof the natural sciences. We have now looked at some of the methods by\nwhich the extremes of heat and cold, in day and night, in summer and\nwinter, and in the tropics and polar regions, are mitigated. The same\nprinciples operate upon the smallest and upon the largest scale. If there\nis need for me to attempt in a formal way to awaken in you admiration for\nthe wisdom and goodness of God shown in all these beneficent arrangements\nfor equalizing temperature, our study has been largely in vain. We have\nonly to remember that all these contrivances are the Lord's designs. He\ncreated the world; he endowed matter with its qualities and forces, and he\ngave it these qualities and forces for the purpose of using it as he has\nused it. He planned all those contrivances by which he secures the comfort\nand the good of man, and the fact that these natural agencies are fitted\nfor moral uses in recovering sinners to holiness and blessedness is but\nthe culmination of its adaptation to the uses of man.\n\n\"This, however, does not complete our course of study. A few other points\nwill demand our attention for two or three more lessons. But while we go\non with our studies of Nature, remember that the physical was created for\nthe sake of the spiritual; the spiritual is more important. Let us not\nsubvert the divine order and sink the high purpose of the creation to mere\nmaterial agencies and contrivances. To know God is greater and better than\nto understand Nature. That we might know and enjoy and glorify the\nCreator was the object of our creation. We cannot express it in better\nlanguage than that employed in the old catechism: 'The chief end of man is\nto glorify God and enjoy him for ever.' That term 'for ever' includes the\npresent life as well as the future. We ought to know, enjoy, and glorify\nGod to-day. I hope that another week may find Ansel with some happy\nexperience in this matter.\"\n\n\n\n\nCHAPTER XIV.\n\nCOMBUSTION.--COAL-BEDS.\n\n\nAnother Lord's Day comes, and no change has taken place with the class\nwhich calls for mention. Ansel still walks in darkness, ready indeed on\nevery occasion to manifest his concern for the salvation of his soul,\ndiligent in reading the Scriptures, frequent in prayer, and giving yet no\nindication of a flagging of his avowed purpose to follow Christ, but he\nreceives no comfort and peace. A painful and distressed interest is\nbecoming more and more concentrated upon him. What will be the end of his\ngroping in darkness? This cannot last always. Unless the hindrance,\nwhatever it be, which prevents the exercise of faith, be seen and removed,\nAnsel will probably soon go back to his former careless state, and, it may\nbe, become tenfold more obdurate than before. He will be likely, on the\none hand, to become self-righteous from his supposed effort to come to\nJesus, and, on the other, discouraged and despairing, feeling that for him\neffort is vain and salvation unattainable. While he remains in this state\nthe very lapse of time is dangerous. All feel concerned for him, but no\nquestions are asked, and the lesson goes on as usual.\n\n\"The method of transferring heat which we are now to examine is wholly\ndifferent in principle from any which we have as yet considered. I refer\nto the production of heat by combustion. The transfer of heat by\ncombustion cannot be compared for vastness with those great movements of\nheat which have before claimed our attention, yet for the comfort and\nwell-being of the human race combustion is exceedingly important. Without\nthat command of heat which combustion gives, man could not rise at best\nabove the savage state, and in fact could hardly exist upon the earth. We\nsmile at the Grecian myth that Prometheus stole fire from the gods and\nbrought it to men in his reed staff, but fire is certainly worthy of being\ncounted one of God's great gifts. But whence comes the heat of combustion?\nIs it a new and original generation of heat, or is it merely a transfer?\nWill some one explain this?\"\n\n\"I don't think that I can tell,\" said Samuel. \"I remember the principles\nyou have given us about the nature and production of heat, but I do not\nknow how to apply them to combustion.\"\n\n\"I did not suppose that you would be able to explain all the phenomena of\nNature at sight, yet the production of heat by combustion is not difficult\nto be understood. The burning of wood and coal is chiefly the union of\noxygen with carbon. The oxygen of the air unites with the carbon of the\ncombustible. The attractive force between oxygen and carbon is very\nstrong. When they unite, the atoms of oxygen dash against the atoms of\ncarbon with great violence. As they dash one upon another their motion is\nlost, but by the laws of transmutation of forces that lost motion\nreappears as heat; that is, the motion of the atoms as they fall the one\nagainst the other is changed to that vibration of the atoms which we call\nheat. The atoms of carbon, in their separation from oxygen, may be\ncompared to weights suspended, ready to fall. Let once the cord be cut,\nand the weight falls and dashes against the earth; its motion in falling\nis lost, and reappears as heat. So carbon is suspended, so to speak,\nwaiting to unite with oxygen. But how is the weight raised? How is carbon\nbrought into this state of suspense, waiting to dash upon oxygen and\ndevelop heat? That is not its natural state.\n\n\"Carbonic acid is found everywhere mingled in small proportions with the\natmosphere. This carbonic acid is nothing else than carbon and oxygen\nunited in the proportion of one atom of carbon to two atoms of oxygen.\nThis is the natural state of carbon. This carbonic acid is the food of\nplants; it is this which supports all vegetable growth. The carbonic acid\nis absorbed by the leaves of plants and trees, and in the hidden\nlaboratory of the leaf, by what process is one of the undiscovered secrets\nof Nature, the carbon is separated from the oxygen, the oxygen is\ndischarged through the pores of the leaf, and the carbon is carried into\nthe circulation to build up the fabric of the woody fibre. That which the\nmost skillful chemist in the world cannot do, except by indirect processes\nand at a high temperature, the leaves are doing directly at the ordinary\ntemperature. Vegetable growth is a deoxidizing process. To accomplish this\nan enormous force is requisite. To separate carbon and oxygen, a force is\ndemanded which is able to overcome their powerful attraction. How shall we\nestimate the strength of this force? In order that they may unite, as in\nthe explosion of gunpowder, solid rocks are torn asunder. The attraction\nof carbon and oxygen is strong enough to tear great rocks in twain. It is\nthis attraction which sends the cannon ball and the shell like meteors of\ndeath upon their errands of destruction. This great force must be\novercome; carbon must be separated from oxygen and built into trees. This\nis the lifting up of the weight. But whence comes the force necessary to\naccomplish this? From the sunbeam. The heat of the summer's sun, employed\nas force, is used to deoxidize carbonic acid. Heat is used, and used up,\nin lifting the weight which in its fall shall generate again a like amount\nof heat. The combustion of wood produces the same amount of heat as was\nneedful to separate its carbon from the carbonic acid of the air.\nVegetable growth is thus a cooling process; heat is withdrawn from use as\nheat, and is employed as force. As force it has nothing to do with\ntemperature. The summer's heat, employed in vegetable growth, reappears\nin the blazing billets of the kitchen fire. Heat is condensed and\nsolidified, so to speak, and placed under man's control. In this\nsolidified form heat may be laid up in store or transported at pleasure.\n\n\"The grandest application of this principle is seen in the formation of\nthe coal-beds. At some early period in the unmeasured ages past, the\ntemperature of the earth must have been much higher than it now is; the\nair was filled with moisture, and carbonic acid abounded. As a\nconsequence, there was an enormous vegetable growth. This, as we have\nseen, is a heat-consuming process. The heat is withdrawn from the air and\nemployed in deoxidizing the carbonic acid. This vast vegetable\ngrowth--enormous ferns and coniferous trees--fell, and was swept by rivers\nor by floods into valleys, or the beds of lakes, or the sea; the sediment\nof the waters covered it, and there, shut up from the air and subjected to\na heavy pressure, this vegetable mass underwent a slow transformation.\nPeter, have you ever seen a coal-pit? I do not mean a coal _mine_, but\nthat which charcoal-burners call a coal-pit.\"\n\n\"I have seen them many a time.\"\n\n\"Tell us, then, how wood is burned to coal without being burned up.\"\n\n\"The wood is set on end, closely packed in the shape of a mound, and then\ncovered with earth. Fire is kindled in the middle of the pile, and just\nenough air admitted through air-holes at the bottom to keep up a slow\nburning. It burns just fast enough to heat and dry the wood without\nburning it up.\"\n\n\"The same process,\" said Mr. Wilton, \"went on in the formation of the\ncoal-beds, but very much more slowly. Under the pressure of earth and\nwater the vegetable deposits lie smouldering, not for a few days, but\nprobably for ages, till nothing but the carbon remains, and that pressed\ninto a solid mass heavy as stone. Veins of coal are found interspersed\nwith layers of earth and rock, layer above layer, and these layers are\ncommonly not level, but more or less inclined and sometimes broken. This\nshows that a deposit of driftwood was made, then a deposit of sand or\nclay, then another deposit of vegetable material and another layer of\nearth. At length, by internal convulsions, the whole surface was raised\nfrom beneath the waters, and in due time the coal-veins were laid open,\nand the coal brought out for the use of man. Then the force so long pent\nup and held in suspense is set free; the stored-up heat of the geologic\nages is brought out for use. The excess of heat in that ancient period is\nhanded down to these later times. How sublime this transfer of heat! It\ncarries us back, in imagination, to the 'heroic ages,' so to speak, of the\nhistory of creation. By other methods heat is treasured up for a day or a\nyear: by this method it is kept in store for myriads of ages. We see that\nthe same natural forces were working in those early ages as to-day, and\nthe same benevolent Creator was arranging the affairs of the world for\nman's advantage. The sunbeam which streamed upon the earth long ages\nbefore man was created is to-day smelting ores, driving machinery,\ndragging ponderous trains of loaded cars, and ploughing the seas with\nfreighted keels. This seems like a fairy-story or a dream, but instead of\nthat it is the soberest of philosophic and scientific truth.\n\n\"We ought also to notice the internal heat of the earth. This has been\nhanded down from the day of creation, it would seem, till the present. No\nnew principle is seen in the earth's internal fires, but a sublime\nillustration of the storing up of heat in a hot body and its slow\nradiation.\n\n\"The origin of the internal heat of the earth we can only conjecture.\nPerhaps God created the various elements separate, uncombined, and allowed\nthem then to combine according to their natural affinities. This sublime\nconflagration of all the elements of the earth would generate the highest\ntemperature which could be produced by combustion. The elements would melt\nwith fervent heat; everything which could be vaporized by heat would be\nturned to vapor. Then radiation of heat would begin. Vapors would sink to\nfluids and fluids turn to solids; a hard crust would be formed on the\nsurface of the globe through which the heat of the still molten mass\nwithin would be slowly conducted and escape. Upon this internal heat the\nearth depends in no small degree for its temperature. The heat generated\nperhaps upon the day of creation helps now to render the earth habitable.\n\n\"That the earth was once in a fluid state and has lost a portion of its\nheat by radiation is indicated by several facts. It is one of the received\nbeliefs among geologists that at some period in the past the temperature\nof the earth was much higher than it now is. The animals and plants which\nflourished during the ages when the coal-fields were deposited show that\nsea and land were warmer than at present. It is believed that the change\nof temperature has taken place on account of the cooling of the earth from\nradiation. The rate of radiation is so slow, however, that no farther\nsensible change of temperature can take place for thousands of\ngenerations.\n\n\"The form of the earth also indicates that it was once fluid. The earth is\nan oblate spheroid, a flattened sphere, and has that degree of flatness\nwhich a fluid mass would assume if revolving at its present rate. The\nearth swells at the equator and rises thirteen or fourteen miles above the\nsea level at the poles. The waters of the ocean move freely and take the\nsame form as if the whole globe were fluid, and the solid parts of the\nearth have the same degree of convexity, which shows that it took its form\nfrom its own rotation upon its axis while in a fluid state. This would\nalso show that in the primal ages, when the earth was in a plastic or\nfluid state, it had the same rate of rotation as at present.\n\n\"The lifting up of the mountain ranges also is best explained by\nsupposing that the earth was once molten. The earth cooled, a crust was\nformed, and by farther cooling and contraction of the molten mass within\nthe crust wrinkled and formed mountain chains. Thus the higher temperature\nof the geologic ages, the form of the earth as if it were a revolving\nfluid mass, and the corrugation of its surface--these, joined with its\npresent internal heat, point to the fact that it was once molten and fluid\nto its surface. The benefits of this heat laid up in store on the day of\ncreation we still enjoy.\"\n\n\"Before the class is dismissed,\" said Mr. Hume, \"I should like to say a\nfew words.\"\n\n\"I have nothing farther to say to-day,\" answered Mr. Wilton, \"and we\nshould be glad to hear you now. Say on.\"\n\n\"I wish only to say that these lessons have led me to such thoughts of\nGod's wisdom and goodness as I never had before. Of course it is not\nstrange that this should be the case with me. I now look at everything\nwith new eyes. It is not merely this one element of heat in Nature that\nmoves my admiration, but I have been led to consider a thousand things in\nwhich the goodness of God is shown. My thoughts of the divine goodness\nare as fresh and interesting to me as my impressions of his righteousness\nand holiness are startling. For years I have tried with might and main to\nlook upon the dark side of the world and to exaggerate its physical evils.\nI have searched for disorder and want of adaptation. As long as I\nmisunderstood the purpose of the creation, I thought I was successful in\nimpugning the wisdom of the arrangements of this physical world. While I\nsupposed that the earth must needs be the Creator's masterpiece in beauty\nand pleasantness and all manner of perfections, designed just to give\nsensual pleasure to its inhabitants, I could find, or thought I found,\nmany faults in the Creator's work. Now I withdraw all my former charges.\nMy eyes are opened. The rougher elements of man's life will henceforth\nhave a new meaning to me. I see that God seeks not so much present\npleasure for men as their holiness. He lays a solid foundation for their\nhappiness. He seeks to render men blessed by bringing them into likeness\nand union with himself. These are new views to me, and I thank my heavenly\nFather that this new light has dawned upon me. I feel now that I can bear\nthe ills of this life cheerfully, understanding that the Lord is using\nthem as a means of spiritual discipline. It seems to me as if this lower\nworld and man's lowly life were already glorified by a beam of light\nfalling from heaven. I hope that my young friends have been as much\nprofited as I have been.\"\n\n\"I rejoice with you, Mr. Hume. 'We know that all things work together for\ngood to them that love God.' This light has shone upon me for many\nyears.\"\n\n\n\n\nCHAPTER XV.\n\nECONOMY OF HEAT.\n\n\n\"In this final lesson I wish,\" said Mr. Wilton, \"to bring before you some\ngeneral views of the whole subject of the agency and management of heat.\n\n\"When Jesus had fed the five thousand men upon the mountain side by the\nSea of Galilee, he said to his disciples, 'Gather up the fragments that\nremain, that nothing be lost.' The Christ who spoke these words was the\nsame Christ by whom 'all things were created that are in heaven and that\nare in the earth, visible and invisible.' These words inculcate the\npropriety of saving, the very opposite of extravagance and wastefulness.\nThe same prudent economy we find in all God's works. Nothing is wasted.\nGod provides bountifully; he is not stinted in his works; we find nothing\nnarrow or mean; his resources are ample for all his undertakings. Perhaps\na careless observer might charge him with prodigality and wastefulness.\nThe wilderness rejoices in beauty and fertility upon which no human eye\ngazes, and which supplies no human want.\n\n    'Full many a gem of purest ray serene\n      The dark unfathomed caves of ocean bear;\n    Full many a flower is born to blush unseen,\n      And waste its sweetness on the desert air.'\n\nRich fruit grows ruddy and golden in the autumnal sun only to fall and\ndecay. How small a part of the seeds which might germinate and reproduce\nthe parent plant ever fulfill this their legitimate object! But this is\nnot waste. As for the beauty with which the unpeopled wastes are smiling,\nwe know not what other beings besides man 'grow glad at the sight.' Fruits\nand grains and seeds were appointed as much to nourish the animal kingdom\nas to reproduce plants and trees. And that which decays is not wasted. The\noak lifts high its leafy arms and does battle with the tempests for a\ncentury, and then having served its purpose in Nature, if man does not\ncall it to the higher mission of serving his purposes, Nature begins to\npull down the structure she has reared and rebuild the elements in other\nforms--such forms as man perchance may need. The fruit that falls and\ndecays is not wasted; it shall blush with golden tints in other forms and\nin other years. God pulls down the old that he may build the new. The same\nelements appear and reappear in a thousand shapes. There is endless\nchange, but no waste. This sentiment, 'Gather up the fragments, that\nnothing be lost,' which is proclaimed throughout all Nature, is uttered\nmost emphatically in the management of heat. God has provided most\nbountiful stores of heat, but has left no heat to go to waste. Will you,\nMr. Hume, suggest one of the general arrangements for the economical use\nof heat?\"\n\n\"I think that the arrangement for economizing heat which ought to be\nmentioned first is the confinement of heat to the locality where it is\nneeded.\"\n\n\"Will you explain that a little farther, Mr. Hume?\"\n\n\"All living creatures are confined near the surface of the earth. They\npenetrate only a few feet into the earth and soar a few hundred feet above\nit. Heat is therefore confined to the region of the earth's surface. It\npenetrates but a little way below the surface, and when warm air rises\ninto the higher regions, heat becomes latent. The higher parts of the\natmosphere are cold, and in the empty spaces of the heavens the\ntemperature is we know not how low. God has provided for heating only that\npart of the world which needs to be heated. I think you spoke of this in\nsome one of the earlier lessons.\"\n\n\"Perhaps I did. But I refer to it again to call especial attention to the\nidea of the economical use of heat. Who will mention another method by\nwhich heat is economized?\"\n\nNo one answered.\n\n\"I asked the question, but did not expect an answer. God shows economy in\nthe use of heat by accomplishing many different results by its agency. I\ndo not mean that the same identical heat accomplishes different results at\nthe same time. The same force cannot accomplish two works. As man cannot\nspend his money and at the same time keep it, no more can heat be used and\nnot used up in that form. The heat which raises the temperature can do\nnothing else at the same time, and when it is employed as force it ceases\nto affect temperature. But by this one agency of heat the Creator brings\nvery various works to pass. Heat expands bodies, relaxes cohesive\nattraction, and brings the chemical affinities into activity. By this\nmeans the elements of Nature are subdued to human uses, seeds germinate,\nall the processes of vegetable life go on, and digestion and nutrition are\ncarried forward in the bodies of animals. By the agency of heat the winds\nblow, the deep waters of the ocean circulate, clouds are formed, dew and\nrain refresh the earth, rivers flow, and all the activities of life fill\nthe world. The employment of one agency for the accomplishment of so many\nworks indicates economy in the expenditure of force and means. Moreover,\nthe same heat appears and reappears again and again, passing from the\nsensible to the latent form and back again, asserting itself alternately\nin raising the temperature and as active force. A beam of heat falls upon\nour world: it is partly absorbed by the earth, and warms it. A part of\nthat warmth is used in setting the chemical affinities in action in the\nsprouting of seeds; a part warms the air by conduction; a part is\nradiated, and being stopped by the vapor in the air, warms it; the heat\nof the air is partly used in the evaporation of water: the vapor formed is\ncondensed and waters the earth, and gives out the heat by which it was\nformed; that raises the temperature of the air; a part of it is used in\ndeoxidizing carbonic acid and building up the forests; the forest tree\nfalls by the woodman's axe, is burned for fuel, and gives out its heat\nagain, or if it falls and decays, the result is the same; the heat given\nout by combustion cooks the laborer's dinner and warms his room, or it\ngoes out again, and is used in preparing food for the growing wheat; that\nwheat is used for food, and by slow combustion in the blood the heat is\nagain evolved, the body is warmed, and the chemical operations of\ndigestion and nutrition are maintained; the heat is radiated or conducted\nfrom the body into the atmosphere, and again raises the temperature and\ngoes to do other work. At last, so far as our earth is concerned, it\nescapes into the stellar spaces, and goes to bless other worlds. In all\nthese operations no heat-force is frittered away and wasted and lost. This\nis one of the accepted doctrines of physical science. Heat is used\nbountifully, but economically and without waste.\n\n\"Even the inequalities and variations of temperature must be counted\neconomy in the use of heat. The heat of midday is not needed at all hours,\nand therefore it is not always provided; the heat of summer is not always\nuseful, and is therefore not given; a higher temperature for a part of the\nyear and a part of the day is necessary, and is bestowed. The smallest\namount of heat is so disposed as to accomplish the largest result. Keep in\nmind, then, the economical aspect of God's management of heat.\n\n\"I would also have you remember how few are the principles involved in all\nthe ways and means for transporting heat and equalizing temperature. All\nthe various phenomena which we have examined can be brought under two\ngeneral principles. The first principle or method is the heating and\ncooling of bodies. Bodies absorb heat; they part with their heat by\nconduction or radiation. If they are heated and cooled without change of\nplace, heat is transported in time, but not in place. If the body be\nremoved from one place to another between the heating and the cooling or\nbetween the cooling and the heating, heat is transported in both time and\nspace. This applies alike to solids, liquids, and gases; each one is a\ncarrier of heat in proportion to its specific heat.\n\n\"The second principle or method is the transportation of heat by the\nchange of sensible to latent heat and its restoration to a sensible state.\nUnder this principle there are four cases:\n\n\"1. Heat is employed in the evaporation of liquids, and is restored again\nto use as affecting temperature by the condensation of the vapor.\n\n\"2. Heat is employed in liquifying solids, and becomes latent thereby, and\nreturns to the sensible state when the liquid solidifies. These two\nprinciples find their grandest application in the changes of water: of\nthis application I have chiefly spoken; but they apply also to other\nbodies--to metals as well as to liquids.\n\n\"3. Heat is rendered latent in the expansion of gases from removal of\npressure, and latent heat becomes sensible by the compression of gases.\n\n\"4. Heat is employed in the deoxidation of carbonic acid or other\ncombinations of oxygen, and is evolved in combustion. While in the latent\ncondition, heat may be kept without loss for an unlimited period of time\nor transported from equator to pole. By the various applications of these\ntwo general principles, all the different methods of equalizing\ntemperature are determined.\n\n\"I would have you remember also that these processes for transporting heat\nand modifying temperature are not confined to the regular changes of days\nand seasons and the permanent differences of zones, but apply to every\npossible difference of temperature. One minute the sun shines out in full\nsplendor; the next, a cloud hides his face and cuts off his fervent beams;\nthe methods employed to soften the heat of the one minute and the chill of\nthe next are the same which equalize the temperature of the seasons.\nEvaporation carries off the heat from the seething tropics, evaporation\ncarries off the excess of heat from the bodies of animals and men. The\nsame methods are equally efficient upon the grandest and upon the smallest\nscale.\n\n\"In this connection let me give one or two illustrations of the delicacy\nwith which general principles adapt themselves to the minutest\ncircumstances. When the earth is wet, it is fitting that evaporation\nshould go on rapidly and remove the excess of water, but when the ground\nis drier, it is fitting that evaporation should be checked and the\nremaining moisture spared. This result is secured not merely by the lack\nof moisture at the surface, but also by the decreased capacity of the\nearth for absorbing heat. A dark color absorbs heat more readily than a\nlighter color, and the earth becomes, as a general rule, darker when wet;\nand lighter when dry. Moist earth, therefore, receives heat more readily\nthan dry earth, and the excessive moisture is the more rapidly carried off\nby evaporation.\n\n\"Another more interesting illustration is presented by the odor of\nflowers. In its place I told you that watery vapor hinders the radiation\nof heat from the earth. Dark heat is absorbed by it. The same is true of\nother gases, and also of the odors of fragrant substances. A bed of\nflowers fills the air around with odors. By these odors much of the heat\nradiated by the earth is stopped. By this means the air around the\nblooming flowers is warmed. The invisible fragrance raises the temperature\nand secures for the blooming plants a more genial atmosphere. The Lord\nprovides for the flowers when most of all they need to be cherished by a\ncongenial warmth.\n\n\"This completes what I have to say to you upon the subject of heat. I\nmight have gone far more into particulars, and extended these lessons over\nsix months instead of three. We started with the design of finding out\nwhether the works of Nature have anything to say about a wise and good\nCreator. We could not examine the whole circle of God's works, and\ntherefore chose a single department--that of heat. I will leave yourselves\nto decide whether we have found marks of divine wisdom and goodness,\nwhether Nature has had anything to say to _us_ about a Creator.\"\n\n\"It seems to me,\" said Samuel, \"that if the works of Nature do not show\nGod's goodness and wisdom, it would be hard to tell what works would show\nthem. I think I shall always, after this, look upon the earth and sky with\nmore interest than I have ever felt in them before; I shall always look\nupon them as having something to do with God.\"\n\n\"We certainly ought,\" said Mr. Wilton, \"to study Nature in such a manner\nand with such a spirit that we shall be led to reverence and worship the\nCreator. Some very good men are afraid of scientific study, as if there\nwere something in it to draw men from belief in the Scriptures and the\nJehovah revealed in them; and it cannot be denied that not a few\nunbelievers have tried to find a foundation and a defence for their\ninfidelity in scientific studies; but such men are not made skeptics by\nearnest and reverent study of God's works: they were unbelievers before\nand aside from physical studies, and they only try to glorify their\nrejection of the Bible and Christ by deifying science and the creation and\nholding them up in opposition to inspired revelations. If ever you find\nthe works of God separating you from God, you may know at once that you\nmisunderstand those works or come to them with a wrong spirit. 'The\nundevout astronomer,' it has been said, 'is mad,' and the same might, with\ngood reason, be said of every undevout student of physical science.\n\n\"In selecting heat for our examination, I did not take the only rich\ndepartment of Nature's works. The practical chemist would find a richer\nand broader field of research, and so would the anatomist and animal\nphysiologist, the geologist, or the physical geographer. I purposely chose\na comparatively narrow field, in order that our course of study might not\nbecome wearisome by its length. You will find ample scope in the fields of\nnatural science for your largest powers, and enough to carry your thoughts\nreverently to the great Creator and Governor.\n\n\"In one respect the study of Nature resembles the study of the Sacred\nScriptures. It is a revelation; it is an embodiment of God's thoughts; in\nit God has expressed himself; and Nature, by most suggestive symbols and\ntypes, teaches much more moral truth and spiritual sentiment than some men\nthink. In the brute creation it gives us, in pantomime, all the virtues\nand graces and all repulsive vices and cruel passions. To this book of\nNature we ought to come without prejudice, reverently inquiring what is\nwritten therein. We must study it thoroughly and interpret it as we\ninterpret the written word, comparing Scripture with Scripture. It is a\ngreat attainment to be able to read and understand the thoughts of God\nembodied in his works.\n\n\"In another respect, the book of Nature and the Sacred Scriptures have\nvery little in common. The Bible is occupied pre-eminently with moral\nduties and spiritual relationship. Its great themes are sin and salvation.\nChrist is the great central truth. One might compare the Scriptures to a\npicture in which one central figure seizes every eye, and by whose\nradiance the whole picture is filled with light, and that central figure\nis Christ; or we might compare the Bible to a sublime oratorio, the\nglorious symphony of the ages; through it all is heard one strain, sweetly\nexultant as angel voices, faintly heard at first amid the sadness of the\nfall, but rising still above the terrific bass of Sinai and its\never-repeating echoes, growing more clear and strong upon the harps of the\nprophets, till its rapturous beauty pours itself triumphant along the\nplains of Bethlehem. In this revelation of salvation from the guilt and\nruin of sin the Bible stands alone. Upon this subject Nature is silent.\nSalvation by Christ is the gem enshrined in the Scriptures. But what is\nthe setting for this gem? The works of God on the earth and in the\nheavens. The prophets were men in sympathy with Nature. How David sung the\npraises of the divine handiwork!--'O Lord, how manifold are thy works; in\nwisdom hast thou made them all.' 'The heavens declare the glory of God\nand the firmament showeth his handiwork. Day unto day uttereth speech, and\nnight unto night showeth knowledge. There is no speech nor language where\ntheir voice is not heard.' How Christ unfolded the deepest spiritual\ntruths by the symbols of Nature! But if the casket be so worthy, what\nshall be said of the gem which is enshrined within? That is the pearl of\ngreat price. To that book which speaks in no doubtful voice of deliverance\nfrom sin let us turn with increasing reverence; and above all, let us come\nto him who came to reveal our God, who came to be as well as to make a\nrevelation of God, being himself 'the brightness of his glory and the\nexpress image of his person.' I am glad that you all now feel that you\nknow him whom to know is everlasting life.\"\n\nFrom these words of Mr. Wilton you will conclude that Ansel has at length\nfound rest in Christ. In another brief chapter I will tell you of his\nexperience, and then bid you adieu.\n\n\n\n\nCHAPTER XVI.\n\nA DAY OF JOY AND GLADNESS.\n\n\nThe reader has already learned that after Ansel had confessed himself an\nanxious inquirer and professed himself willing to obey Christ, he remained\nthree or four weeks still in darkness. Others found peace in believing,\nbut he felt no joyful confidence that Christ had received him and forgiven\nhis sins. He sometimes felt almost discouraged, and sometimes was tempted\nto complain of God for not treating him as favorably as others, or to feel\nchagrined because others were rejoicing, while he found no light. But he\nfought against these evil thoughts and insinuations of Satan, and did not\nflag in his private devotions or cease to confess himself, always and\neverywhere, an anxious inquirer, still in darkness, but desiring to find\nthe grace of God. If ever he was tempted to push away all concern about\nsalvation and return by force to his former careless state, the words of\nChrist would come to his mind: \"Will ye also go away?\" and Peter's answer,\n\"Lord, to whom shall we go? for thou hast the words of eternal life.\" The\nalternative, salvation by Christ or the loss of his soul, stared him in\nthe face.\n\n    \"I can but perish if I go;\n      I am resolved to try;\n    For if I stay away, I know,\n      I must for ever die.\"\n\nGreat interest was felt for him and much prayer was offered in his behalf,\nbut he seemed to make no progress toward a better state. Mr. Wilton had\ntalked with him, but had failed to discover what it was that hindered his\nhumble acceptance of the grace of Christ. After long and anxious musing\nupon Ansel's character and surroundings and the previous conversations\nwhich he had had with him, Mr. Wilton determined to probe him more fully.\nFor this reason he invited Ansel to his study, where the following\nconversation transpired:\n\n\"Good-morning, my young friend; how do you find yourself to-day?\"\n\n\"I am feeling, I think, very much as when I was here a week ago.\"\n\n\"Are you becoming discouraged and almost ready to give up all effort to\nfollow Christ?\"\n\n\"I do sometimes feel very much discouraged, but I am not ready to give up\nmy interest in religion.\"\n\n\"Have you no more enjoyment in reading the Scriptures and in your prayer\nin secret than you had a week ago?\"\n\n\"I think that I am trying to do right in doing these things, and I enjoy\nthem better than I should if I felt that I was doing something wrong, but\nI do not feel as I think a Christian ought to feel.\"\n\n\"Are your thoughts and feelings and opinions about Christ and salvation\nthe same as they were six weeks ago?\"\n\n\"I think they are very different.\"\n\n\"I am glad to hear that; but can you tell how they are different?\"\n\n\"At that time I felt that I was a sinner, but was fighting against that\nfeeling. I wished that Christ would let me alone, and that the Holy Spirit\nwould not trouble me. But now I very much wish that I may feel my sins,\nand that Christ may come to me and save me. I wish to follow the Spirit.\"\n\n\"Did you expect a month ago that at this time you would be feeling and\nacting as you now feel and act?\"\n\n\"No, sir; I meant then to fight it through, and not let anybody know how I\nfelt.\"\n\n\"Do you wish now that you had fought it through, as you proposed, and kept\nall your feelings to yourself?\"\n\n\"I am very thankful that I did not keep on hiding my feelings. I almost\ntremble to think what the result would have been.\"\n\n\"You have said that you wish to spend your life in serving Christ. Does it\nseem to you a hard and painful work--a work that you would get rid of if\nyou could--or does working for Christ and confessing Christ before men\nseem attractive?\"\n\n\"I think his service seems pleasant; there is no other life that seems\nhalf as pleasant.\"\n\n\"Do you believe that Christ is able to save you?\"\n\n\"I suppose he is. If he cannot save me, there is no hope for me, for I\ncannot save myself.\"\n\n\"Do you believe that he is willing to save you?\"\n\n\"I think he is, if I come to him and trust in him. I suppose he is willing\nto save all who come to him.\"\n\n\"Are you unwilling to come to him--to trust him and submit to him?\"\n\n\"I don't know; I have tried to come to Christ, but I have met with no such\nchange as I have always supposed that a Christian ought to have.\"\n\n\"What do you think it is that hinders your coming into light and joy as\nothers have done?\"\n\n\"I cannot tell. I suppose it must be something or other in myself, but I\ncannot guess what it is.\"\n\n\"I would like to ask you a few questions which you may think rather close\nand personal, and which you may find it hard to answer frankly. You know\nthe spiritual adviser, as well as the physician, must first of all find\nout the condition of the patient.\"\n\n\"I am willing to have you ask any questions you please, and I will try to\nanswer them as well as I can.\"\n\n\"Did you ever think, Ansel, that you were very ambitious?\"\n\n\"I knew that, like many others, I was a little ambitious, but I never\nthought that I was very much so.\"\n\n\"Perhaps you were more ambitious than you thought. You know that you would\nwork day and night rather than not stand at the head of every class you\nwere in. On the play-ground you asserted your position as leader in every\ngame. Did you not carry the same idea of being chief into your plans and\nexpectations for the future? You were ambitious of standing the very first\nwhatever course of life you might follow. Was not this so?\"\n\n\"I don't know: I can't deny it; I think it was.\"\n\n\"It is possible, Ansel, that you are trying to carry the same ambition\ninto the kingdom of Christ. Perhaps you have wished in conversion some\nbrilliant experience which would draw attention to you. Tell me how this\nis. Would you be satisfied to have a commonplace experience, such as\nthousands of others have, which would attract no special notice? Have you\nnot formed an idea of the great and brilliant change you must pass\nthrough, and are you not refusing to take anything else from the Lord's\nhands?\"\n\nTears gathered in Ansel's eyes, and his face worked painfully. At length\nhe answered: \"Your question is a hard one to answer, but I cannot deny it;\nI am afraid it is so. I have heard persons tell of the great load of sin\nlike a pack on their shoulders, and of the earth seeming as if it would\nopen and swallow them up, of sleepless nights and unspeakable anguish, and\nthen of light and joy, so that they could never doubt that they were\nconverted. I have been expecting that I was to have such an experience,\nbut I have not seen it. Is it wrong to wish for such an experience?\"\n\n\"It is certainly wrong to _insist_ upon such an experience. God leads each\none to himself in his own chosen way. There was but one Saul, whom Christ\nmet and blinded with the dazzling light. As a general rule, when a sinner\nmakes up his mind in what way he will be converted, the Lord will\ndisappoint him. If he fixes in his mind that he will not come to an\nanxious-seat, or will not confess his feelings till he can say that his\nsins are pardoned, or will not do anything else, the Lord will very\nlikely bring him to do the very thing he resolved that he would not do.\nIf he attempts to bring his ambitious aspirations into Christ's kingdom,\nhe will be disappointed. 'The first shall be last and the last first.' Men\nbecome great in Christian service by counting themselves the least of all,\nand humbling themselves to become the servants of all. You need to examine\nyourself in this matter. If you have looked for something great and\nstartling, be contented with something small and commonplace. It is an\nunspeakable privilege to be brought into Christ's kingdom in any manner.\nIt is sometimes a great blessing to have a very unmarked and plain style\nof conversion. Such a convert is compelled to look to the truly scriptural\nevidences of a change of heart instead of resting upon the evidence, often\ndeceptive, of a great and sudden illumination or a fancied voice from\nheaven. Some of the greatest and best of men have been unable to tell at\nall the time of their conversion. Richard Baxter could not tell even the\nyear of his change. The best experiences I have known have been those\nwhere the converts could tell very little about themselves; they had been\ndoing something else besides looking into themselves to watch the motions\nof their own thoughts.\"\n\n\"I will try to do as you say. But what kind of evidence am I to look for?\"\n\n\"The same kind of evidence which you now look for in me or any other\nChristian. It is not one thing to come to Christ and another thing to\nfollow Christ. The best evidence that a sinner has come to Christ is that\nhe actually follows Christ and serves him. 'By their fruits ye shall know\nthem.' 'Bring forth fruits meet for repentance,' said John the Baptist.\nBring forth fruits that show that your thoughts about sin, and about\nChrist, and about the service of Christ have been changed. Look for the\nsame kind of evidence in yourself that you would look for in any stranger\nwhom you should meet. But above all things take the words of Jesus as true\nand rest on them; consecrate yourself to Jesus with all the heart; with\nlowliness of mind hold yourself ready for any work or any sacrifice; you\nwill find that evidences will take care of themselves. When men come into\nsympathy with Christ, when they believe his words, walk with him, and talk\nwith him, and bear the cross with him, when they enter into a partnership\nof service and suffering with Christ,--the Spirit bears witness with their\nspirits that they are born of God.\"\n\n\"I will try to follow your advice, and am very thankful that you have\nspoken about my ambitious spirit.\"\n\n\"Another caution I wish to give you. Do not think that you, by any methods\nor by cherishing any spirit, are to make yourself fit to be saved. If you\nare saved at all, Christ must take you as a sinner, and a great sinner. If\nyou get rid of your spirit of pride, it will be by Christ's saving you\nfrom it. Let me also suggest to you that which a consideration of your\nassociations suggested to me, that you may have stumbled at the idea of\nbaptism. You must have heard baptism spoken of very disrespectfully, and\nit is possible that you may have learned to look upon it as a humiliation\nand a reproach. You may have recoiled from the thought of submitting to\nit.\"\n\n\"That was my feeling once, but since I have been willing to have my\nfeelings known I have ceased to be afraid of what those who despise\nreligion may say.\"\n\n\"Be careful now, since you feel that your sympathies are with the\nChristian band, that your love of greatness does not lead you to resist\nthe Spirit. Be willing to be small. Be thankful for small gifts. I trust\nthat your present feelings will before long give place to a humble trust,\na childlike confidence, and a holy boldness in Christ, and that your\nusefulness in the kingdom of God will be all the greater because he now\nrequires you in the beginning to trample under foot your budding pride and\ndie to all human ambitions.\"\n\nWhen Ansel gave up the idea of a wonderful conversion, a sudden\nillumination which should bring with it something of eclat, he found that\nhe could understand the Scriptures better and have more enjoyment in his\nreligious duties. While he humbled himself, hoping for little, he found\nhis soul soon filled with a deep, quiet joy.\n\nThe next Saturday afternoon was the regular time for the covenant-meeting,\nand also, according to custom, for hearing the experiences of any who\nwished to unite with the church by baptism. Ansel, Peter, and Mr. Hume\ncame, along with others, to present themselves to the church. In regard to\nMr. Hume there had been much speculation among his former comrades as to\nwhat course he would take. Some said: \"Mr. Hume will never wet the sole\nof his foot in that river. Don't you remember how he used to laugh at the\nidea of being plunged in the river in honor of a dead man? He may talk in\nmeeting, but it is a very different thing to go down into the river with\nthe whole hillside covered with people.\" Others said: \"We can't tell what\nhas come over him, but he will not go back now. He has gone too far to\nretreat.\"\n\nSome even ventured to approach Mr. Hume himself with their raillery:\n\n\"What do you think now of being dipped in the river in honor of a dead\nman?\"\n\n\"I think that I would be willing to be baptized a thousand times if I\ncould recall by that means what I have spoken against baptism.\"\n\n\"And what, Mr. Hume, about the ice water?\"\n\n\"You know and I know,\" he answered, \"that we always respected those who\ndid not shrink from cold water for Christ's sake. What effeminacy, what\nmore than effeminacy, for a resolute man to hesitate and tremble at\nbaptism! We should be ashamed of such weakness in any worldly matter. I\nhave given you occasion for all your raillery, but as I once was a leader\nin evil, so I wish that I might lead you to better things.\"\n\nAnsel, Peter, and the rest gave an account of their religious experiences,\nand last of all Mr. Hume.\n\n\"What leads you,\" asked Mr. Wilton, \"to present yourself to the church,\nasking for baptism?\"\n\n\"I think that the love of Christ leads me. I have done a great deal\nagainst Christ, and now I wish, if possible, to do something to show my\nlove for him. I come to obey the word and example of Christ by being\nburied with him in baptism.\"\n\nThey were received for baptism, and the time of administration fixed at\nhalf-past twelve o'clock the next day.\n\nThe Lord's Day was cold and blustering. Many were disappointed, for they\nhoped that the day would prove warm and sunny. But the blustering day did\nnot prevent the gathering of a great company by the riverside. As the\ncongregations left the churches they turned their steps toward the place\nof baptism. Ungodly men turned out, and those who never came to hear the\npreaching of the gospel flocked together to see the gospel preached by\nthis symbolic service. The word had gone out that Mr. Hume was to be\nbaptized, and this drew together his former associates. At the place\nchosen the river swept around in a gentle curve and the bank rose up like\na magnificent amphitheatre; while just above, the land put out into the\nwater and threw the current upon the opposite side. Here gathered almost\nthe entire population of the village to witness that simple and solemn\nservice which from the days of John the Baptist has thrilled so many\nhearts. The candidates came warmly clad, brought from their own homes in a\nclose carriage. Gathered there, the little band of Christians, surrounded\nby so great a cloud of witnesses, first sang the hymn commencing:\n\n    \"Thou hast said, exalted Jesus,\n      Take thy cross and follow me;\n    Shall the word with terror seize us?\n      Shall we from the burden flee?\n          Lord, I'll take it,\n      And rejoicing follow thee.\"\n\nThen Mr. Wilton read with a voice that reached all the company a few\npassages from the New Testament which authorized and commanded that\nservice. After that he prayed that the joyful presence of Christ might\nattend those about to follow him in baptism, that believers might be\nencouraged, and careless sinners awakened. One by one the converts were\nburied with Christ, and one by one they came up out of the water,\nforgetting all else in the joy of obedience. They sang the words\nconsecrated by use at so many riversides:\n\n        \"Oh how happy are they\n        Who their Saviour obey,\n    And have laid up their treasure above!\n        Tongue can never express\n        The sweet comfort and peace\n    Of a soul in its earliest love.\"\n\nThese words found a response in many hearts.\n\nHigh up upon the river bank were gathered a little knot of mocking\nunbelievers. One among them, seven years before, had publicly professed\nhis faith in Christ. For a little time he seemed to be treading in the\nLord's ways, but falling among evil associates, he not only neglected\nChristian duties, but became a professed unbeliever. He read infidel books\nand loaned them to others. He sought to sow the seeds of unbelief wherever\nhe went. Upon this Lord's Day he stood with others profanely mocking at\nthe sacred service. With shivering, tremulous accents he exclaimed, \"Poor\nHarry Gill is very cold; I would not go into the water to please any\nChrist for five hundred dollars.\" That young man went home with deep\nconviction of sin upon him. Two days after, Mr. Wilton was called at ten\no'clock at night to visit him. He was trembling like an aspen leaf with\nhis deep anguish of conscience, and for two days and nights his body shook\nunder his fear. Then little by little faith took the place of fear, and\nhope smiled upon him. He was the next person whom Mr. Wilton baptized.\n\nLook in upon the Christian band assembled that Lord's Day evening. Upon\nthe faces of those who had been baptized there was no sign that the\nservice of that day had been painful; if they had done the duty as a\ncross, the cross must have been quickly followed by a crown of joy, for\nevery face was radiant with light. Among them was one little girl twelve\nyears of age whose face, as she rose from the water, shone like the face\nof an angel, and the transfiguration of that moment had hardly begun to\nfade away. Ansel was peacefully happy, and from the face of Mr. Hume the\nold look of dissatisfaction was all gone; his soul had entered into rest,\nand he felt at home. Every one of them testified that it had been the\nhappiest day of his life. They declared themselves willing for Christ's\nsake to be baptized a hundred times if he commanded. They had already\nfound that \"in keeping his commandments there is great reward.\"\n\nI should be glad, kind reader, to trace with you the Christian course of\nthese disciples through the years that follow. But we must leave them. I\nam sure, however, that their course will be upward. Their experience was\nnot the mere effervescence of fickle feeling. The word of God germinated\nin their hearts; they had root in themselves. They believed, they believed\nthe truths of the gospel, and therefore they felt, and therefore they\nacted. \"Whatsoever is born of God overcometh the world,\" and believing\nthat they were truly born of the Spirit, we are confident that \"he which\nhath begun a good work in them will perform it until the day of Jesus\nChrist.\"","title":"Curiosities of Heat","tradition":"scripture-revelation","translated_text":null,"word_count":65883}