Augustin Fresnel (1788-1827) shocked the scientific elite with his unique understanding of the physics of light. The lens he invented was a brilliant feat of engineering that made lighthouses blaze many times brighter, farther, and more efficiently. Battling the establishment, his own poor health, and the limited technology of the time, Fresnel was able to achieve his goal of illuminating the entire French coast. At first, the British sought to outdo...