The name "Leicester" comes from a later owner, the Earl of Leicester, who bought it in 1717. But its most famous modern owner? .
Leonardo said: No.
And it just so happens to be one of the most expensive books on planet Earth. Despite the fancy name, this isn't a dusty medieval poem. It is a 72-page scientific notebook written entirely by Leonardo between 1506 and 1510. It is a firehose of genius, covering geology, astronomy, optics, hydrodynamics, and paleontology. the codex leicester
In 1994, the Microsoft founder paid for the manuscript at a Christie’s auction. That’s roughly $500,000 per page. At the time, it was the most expensive book ever sold. (Gates later had it scanned into a digital format for Windows 95 CD-ROMs—a perfect marriage of Renaissance curiosity and digital futurism). Water: The Star of the Show What did Leonardo obsess over in these 72 pages? Water.
But there is another Leonardo. A Leonardo of obsessive curiosity, of messy reverse-script handwriting, and of questions so vast they stretched the limits of 16th-century science. The name "Leicester" comes from a later owner,
Why does water swirl down a drain? Why do mountains look blue in the distance? Why is the sky blue?
That Leonardo lives in the Codex Leicester . Leonardo said: No
He argued that the fossils were proof that the mountains had once been the beds of ancient seas, lifted up over incredibly long periods of time. He realized the Earth was ancient, shaped by slow, relentless processes like water erosion—not a single catastrophe. This put him centuries ahead of modern geology. If you ever get the chance to see the Codex in person (it travels occasionally), you’ll notice something odd. The text is written in Italian, but it’s backwards—from right to left.