Margherita Cole writes: “Painter, inventor, and scientist Leonardo da Vinci paved the way in many fields during his lifetime. One of the reasons why historians know so much about the Renaissance man is because of the numerous notebooks he kept from the 1480s until his death in 1519. During his lifetime, da Vinci accumulated more than 13,000 pages of notes and drawings. While not all of these have been translated or digitized yet, a select few have, and they can be viewed online for free.”