Leonardo da Vinci, Codex Leicester (Sheet 1A, folio 1r), 1508–10, ink on paper, 11 2/3 x 8 1/2 in., Courtesy of Bill Gates, © bgC3

The North Carolina Museum of Art has an extraordinary treat for visitors beginning October 31: The Codex Leicester, a 500-year-old notebook of largely scientific writings by Leonardo da Vinci.

Named after Thomas Coke, (later the Earl of Leicester), who purchased it in 1719, it consists of 36 folios, each written with sketches of the topics Leonardo discusses. Of all of Leonardo’s 30 scientific journals, the Codex may be the most famous, holding the top sale price of any book when Bill Gates purchased it for US $30,802,500.

The manuscript is a mixture of Leonardo’s observations and theories on astronomy; the properties of water, rocks, and fossils; air, and celestial light.

The topics include:

• an explanation of why fossils can be found on mountains. Leonardo
believed that mountains had previously formed sea beds, which were
gradually lifted until they formed mountains.

• the movement of water. Leonardo wrote about the flow of water in rivers,
and how it is affected by different obstacles put in its way. From his
observations he made recommendations about bridge construction and
erosion.

• the luminosity of the moon. Leonardo speculated that the moon’s surface
is covered by water, which reflects light from the sun. In this model,
waves on the water’s surface cause the light to be reflected in many
directions, explaining why the moon is not as bright as the sun. He
described the phenomenon of planetshine one hundred years before
the German astronomer Johannes Kepler proved it.

The Codex consists of 18 sheets of paper, each folded in half and written on both sides, forming the complete 72-page document. At one time the sheets were bound together, but they are now displayed separately. It was handwritten in Italian by Leonardo, using his characteristic mirror writing, and supported by copious drawings and diagrams. An interactive display will allow visitors to explore a translation of the text on computer screens. Additionally, modern and contemporary works that complement the themes and ideas revealed in the Codex Leicester will be on view.