PREFACE

What was the cause of this reluctance to paint? Why was it that Leonardo did not satisfy the requests of a refined princess, nor the general expectations of his native city? A few dates will provide a clear answer. The Codex on the Flight of Birds Original Italian: Codice sul volo degli uccelli. This notebook, now in Turin, contains Leonardo’s most advanced theories on aerodynamics and his designs for a flying machine. dates back to 1504 (V. U., 5 r.); “V. U.” refers to Volo degli Uccelli (Flight of Birds), folio 5 recto. his mathematical work regarding spherical sections dates to 1505. (R., § 1374.) “R.” likely refers to Jean Paul Richter’s seminal 1883 compilation of Leonardo’s literary works. His research into perspective, which began even before 1482; his studies of anatomy, conducted systematically since 1489; and those of mechanics, which kept him occupied before 1497, all continued in Florence after 1500. These were joined by his studies on the canalization of the Arno River, which gave birth and life to the modern principles of hydraulics and terrestrial dynamics. Leonardo proposed a massive engineering project to make the Arno navigable between Florence and the sea, bypassing its more treacherous stretches. On May 22, 1508, as if crowning a long period of tireless scientific activity, an idea emerged in Leonardo’s mind for a temporary general reorganization of his manuscript notes:

“And this shall be a collection without order,” he writes as he begins the British Museum Codex, Now known as the Codex Arundel, held by the British Library. It is a dense collection of notes on various subjects including physics and geometry. “drawn from...”