Codex on the Flight of Birds is a relatively short codex

Codex

A codex is a book in the format used for modern books, with multiple quires or gatherings typically bound together and given a cover.Developed by the Romans from wooden writing tablets, its gradual replacement...

 of circa 1505 by Leonardo da Vinci

Leonardo da Vinci

Leonardo di ser Piero da Vinci was an Italian Renaissance polymath: painter, sculptor, architect, musician, scientist, mathematician, engineer, inventor, anatomist, geologist, cartographer, botanist and writer whose genius, perhaps more than that of any other figure, epitomized the Renaissance...

. It comprises 18 folios and measures 21 × 15 centimetres. Now held at the Biblioteca Reale in Turin

Turin

Turin is a city and major business and cultural centre in northern Italy, capital of the Piedmont region, located mainly on the left bank of the Po River and surrounded by the Alpine arch. The population of the city proper is 909,193 while the population of the urban area is estimated by Eurostat...

, Italy, the codex begins with an examination of the flight

Bird flight

Flight is the main mode of locomotion used by most of the world's bird species. Flight assists birds while feeding, breeding and avoiding predators....

 behavior of bird

Bird

Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...

s and proposes mechanisms for flight by machines. Da Vinci constructed a number of these machines, and attempted to launch them from a hill near Florence

Florence

Florence is the capital city of the Italian region of Tuscany and of the province of Florence. It is the most populous city in Tuscany, with approximately 370,000 inhabitants, expanding to over 1.5 million in the metropolitan area....

. However, his efforts failed.

In the codex, Da Vinci notes for the first time that the center of gravity

Center of gravity

In physics, a center of gravity of a material body is a point that may be used for a summary description of gravitational interactions. In a uniform gravitational field, the center of mass serves as the center of gravity...

 of a flying bird does not coincide with its center of pressure

Center of pressure

The center of pressure is the point on a body where the total sum of a pressure field acts, causing a force and no moment about that point. The total force vector acting at the center of pressure is the value of the integrated vectorial pressure field. The resultant force and center of pressure...

.

Sources

• Cremante, Simona. "Leonardo Da Vinci". Giunti, 1698.
• Crispino, Enrica; Pedretti, Carlo; Frost, Catherine. "Leonardo: Art and Science". Giunti, 2001. ISBN 8-8090-1511-8
• Pedretti, Carlo. "A Chronology of Leonardo Da Vinci's Architectural Studies after 1500". Geneva: E. Droz, 1962.