Vol. I: VII. On the Proportions and on the Movements of the Human Figure: 357.
The Da Vinci Notebooks
The loins or backbone being bent. The breasts are are always lower than the shoulderblades of the back.
If the breast bone is arched the breasts are higher than the shoulderblades.
If the loins are upright the breast will always be found at the same level as the shoulderblades.
188:175 : See Pl. XXII, No. 1.