Caption:
Leonhard Euler (1707-1783), Swiss mathematician and physicist who made discoveries in a wide range of fields, including geometry, infinitesimal calculus, trigonometry, algebra, number theory, continuum physics, lunar theory, and graph theory, to name a few. His eyesight grew worse over his career, and by 1735 he was nearly blind in his right eye. He believed his cartography work for the St. Petersburg Academy caused this blindness.