Fol. 10v

The flight of Leonardo Leonardo observes how birds exploit rising currents to gain altitude, following trajectories that are circular and, in cases where they find themselves against the wind, linear as well.
This is an important page for the history of science: the scientist from Vinci comprehends and describes precisely the techniques of flight that are used today by gliders.

«Se l'uccello vorrà voltarsi rapidamente su uno dei due lati e continuare il suo movimento circolare, esso batterà due volte le ali su quel lato remando le ali all'indietro e mantenendo ferma l'ala opposta, ovvero con un solo battere contro due dell'ala opposta»
(If the bird wants to turn rapidly over onto one of its two sides and continue its circular movement, it flaps its wing on that side twice, putting its wings back, and keeping the opposite wing still, or with a single flap against two flaps of the opposite wing.)

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