The stupendous character of the natural convulsion that took place about 80,000 years ago, will be apparent from the fourth map. Daitya, the smaller and more southerly of the islands, has almost entirely disappeared, while of Ruta there only remains the relatively small island of Poseidonis. This map was compiled about 75,000 years ago, and it no doubt fairly represents the land surface of the earth from that period onwards till the final submergence of Poseidonis in 9564 B.C., though during…