Significance

• The Codex Leicester contains some of da Vinci's most important thoughts on astronomy and geology. The Codex describes da Vinci's theory that the moon reflects the light of the sun--an accurate observation--because its surface is covered with water--not accurate.
  
  

Identification

• The Codex was named after it was purchased by Thomas Coke in 1717. It was later briefly known as Codex Hammer after Armand Hammer, who bought it in 1980.
  
  

Style

• The Codex is written in Italian. Da Vinci's also made extensive use of his distinctive "mirror writing," and made numerous drawings in the margins.
  
  

Exhibits

• The Codex typically goes on display once a year, in a different city throughout the world. In 1997 it was displayed at the American Museum of Natural History in New York City.
  
  

Purchase Price

• The Codex Leicester is known as the worlds' most expensive book, after Bill Gates purchased it for over $30 million in 1994. Gates renamed it the Codex Leicester after his purchase.