Thanks to Cambridge University and its digital library, six books of Sir Isaac Newton's work on gravity and calculus — including Newton's personal annotated copy of the seminal Philosophiæ Naturalis Principia Mathematica — are sitting on digital shelves, ready for your perusal. The one-of-a-kind 17th century books and diaries are provided in their original, tattered form and are read (if you're comfortable with old English or Latin) in an online viewer. Cambridge says it'll be bringing the majority of its (world's largest) Newton collection and more books representing the foundations of science and faith soon. Thankfully, there's no login required, so check the source link and take a look at some of the most important works in the history of science.

Lead Image Credit: ben.gallagher (Flickr)