The Da Vinci Notebooks at sacred-texts.com
Which is the part in man, which, as he grows fatter, never gains flesh?
Or what part which as a man grows lean never falls away with a too perceptible diminution? And among the parts which grow fat which is that which grows fattest?
Among those which grow lean which is that which grows leanest?
In very strong men which are the muscles which are thickest and most prominent?
In your anatomy you must represent all the stages of the limbs from man's creation to his death, and then till the death of the bone; and which part of him is first decayed and which is preserved the longest.
And in the same way of extreme leanness and extreme fatness.