Cracking the Code - da Vinci's trade secrets!

Inventors in most of the world have trademark laws and patents to protect their creations. But how did one of the most prolific inventors in history keep his secrets safe-with pirates and spies out to steal his secrets?

Mirror Writing

Before there were copyright laws, there were pirates who would steal the ideas and creations of inventors, artists and musicians and claim them for their own. In Leonardo’s time, there was no law against it—and no Internet to search for copycats.


To keep his discoveries, inventions and ideas secret, Leonardo developed a system of mirror writing—writing from right to left, and often with unusual marks and punctuation—to throw copycats off the mark. But there's another reason many experts think Leonardo adopted this reverse-writing system: he was left-handed. And as Charley, a leftie herself, notes, smudging is a common side effect. Before the invention of the ballpoint pen in the 20th century—and for an artist in particular—smudging one's sketches made of ink, charcoal and chalk would have been a serious hazard of the trade.

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