When Isaac Newton was first developing the mathematical theories that would later form the foundations of Calculus, many of his drawings, equations and calculations found their way into an unassuming notebook (known at the time as a "waste book"), the original cover of which is pictured on the far left of the image up top.

That was over 400 years ago. But now, Newton's waste book is just one work in an extensive selection of scientific and mathematical manuscripts by the brilliant thinker that has just been made available online, free of charge, for all to see.

"Anyone, wherever they are, can see at the click of a mouse how Newton worked and how he went about developing his theories and experiments," said Grant Young, the library's digitization manager, in a press release. "Before today, anyone who wanted to see these things had to come to Cambridge. Now we're bringing Cambridge University Library to the world."

There are roughly 4,000 pages of material available right now, including Newton's annotated copy of *Philosophiæ naturalis principia mathematica*, as well as pages from his college notes.

Even to the untrained eye, the pages of Newton's notebooks belie an almost unbelievable intelligence. At one point, while flipping through this notebook from Newton's days as an undergraduate at Trinity College (the cover of which is featured at the center of the top image, along with the words "not fit to be printed"), I thought I'd happened upon a doodle of some clouds, only to realize that Newton had actually been musing on the nature of fluid dynamics (which, for most of us, is pretty dense subject matter as far as doodles are concerned). [Cambridge Digital Library via WIRED]

*All images via Cambridge Digital Library
The top image comprises the front page of Newton's "Waste Book," the first page of his Trinity College Notebook, and the front page of his annotated copy of Principia; the fluid dynamics figures are from page 199 of Newton's Trinity College Notebook*