Codex on the Flight of Birds

Overview

The Codex on the Flight of Birds is a small but extraordinarily focused manuscript of 18 folios dealing with the mechanics of bird flight and Leonardo's designs for human-powered flying machines. It represents one of the most concentrated examples of Leonardo's scientific method — careful observation of nature leading to engineering application.

A Stolen Manuscript

This codex was originally an appendix to Paris Manuscript B — described in Count Arconati's 1636 donation as having at the end a small "volumetto" of eighteen pages containing various mathematical figures and drawings of birds. It was abstracted at some time before 1848 by Count Guglielmo Libri, who frequently had access to the manuscripts in the Institut de France.

In 1868 it was sold by Libri to Count Giacomo Manzoni of Lugo. In 1892 it was acquired from Count Manzoni's heirs by M. Sabachnikoff, who published it in 1893 as Il Codice sul Volo degli Uccelli (edition by Piumati and Sabachnikoff, Paris). It was subsequently presented to the Royal Library at Turin.

Contents

Leonardo studies the flight of birds from multiple angles:

• The mechanics of wing movement — upstroke and downstroke
• How birds use wind currents and thermals
• The relationship between a bird's center of gravity and its wing movements
• Gliding versus powered flight
• The anatomy of bird wings
• Applications to human flight — the design of the "great bird"

The Great Bird

The codex contains Leonardo's famous prediction about human flight: "The great bird will take its first flight from the summit of Mount Cecero, filling the universe with amazement, filling all writings with its fame, and bringing eternal glory to the nest where it was born." Mount Cecero (Monte Ceceri) overlooks the town of Fiesole near Florence.