Fol. 2r

Codex on the Flight of Birds of Leonardo Reflections on the force of gravity.
The actual laws of gravitation would only be discovered a century and a half later by Newton.
Here Leonardo writes that if a body moves towards another it is because the matter in which it is found – that is, air – is not capable of providing sufficient resistance to keep the body from falling.

«gravità si causa dall'uno elemento situato nell'alto e si muove per la linea più breve verso il centro non per sua scelta né perché il centro a sé la attragga, ma perché il mezzo in cui si trova non gli oppone sufficiente resistenza»
(Gravity is caused by one element situated on high [above another] and moves along the shortest line towards the centre [of the other], not by choice nor because the centre is attractive in itself, but because the medium in which it is found does not pose sufficient resistance.)

NOTE. For each page of Leonardo’s Codex we provide a brief summary, with the quotation of one that page’s most significant passages edited in modern Italian, with an English translation.

translation by Kim Williams