Nearly five centuries ago，Leonardo da Vinci had notions.later proved correct.about fossils，about the circulation of theblood，about the Earth not being the center of the universe，aboutfalling bodies，and about anatomy. His close observation andamazing skill at drawing were such that his pictures of waves andbubbles in water could be improved on only by a slow-motioncamera.But his genius went for naught.He kept these ideas tohimself，writing them in code in voluminous notebooks，so thathis contemporaries knew little of his ideas and remained unin－fluenced by them. Most of these writings remained unpublisheduntil the nineteenth century.Two lost works were found in inthe National Library of Spain in Madrid.
将近个世纪前，列奥纳多·达·芬奇就有了许多后来被证明是正确的见解。比如关于化石，关于血液循环，关于地球不是宇宙中心，关于落体，关于解剖等。他极为细致的观察和令人惊异的画图技术使得他画的波浪及水中的气泡非常精确，只有快速摄影机拍的照片才能改进。可是，他的天才没有起作用。他从未把他的这些见解告诉过别人，而是用密码写在浩瀚的笔记中，因此他同时代的人很少知道他的想法，因而也没有受到他这些想法的影响。这些著作的大部分直到世纪才发表。两本失传的著作直到年才在马德里的西班牙国家图书馆中被发现。