Augustin Fresnel (17881827) 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 the new Fresnel-equipped lighthouses as a matter of national pride. Americans, too, resisted abandoning their primitive lamps, but the superiority of the Fresnel lens could not be?denied for long. Soon, from?Dunkirk to Saigon, shores were brightened with it.? The Fresnel legacy played an important role in geopolitical events, including the American Civil War. No sooner were Fresnel lenses finally installed along U.S. shores than they were drafted: the Union blockaded the Confederate coast; the Confederacy set about thwarting it by dismantling and hiding or destroying the powerful new lights.It is rare that we see a lighthouse-related book, historical in nature, with the level of research that was put into?With his frantic pace of invention and early death, hes just like those romantic heroines of 1830s Paris burning themselves up through their passions, said the historian Theresa Levitt, whose new book isFresnel indeed lit up his country and the world.[F]ascinating book&Levitts writing captures the mix of scientific rigor and cultural shifts in a way that mirrors the sea voyages of the daya journey fraught with uncertainty, but in the end, guided to success by Fresnels lighthouse lenses.Theresa Levitt interweaves the personal triumph of the French physicist Augustin Fresnel with his pathbreaking work on the nature of light in her fascinating recounting of how the coasts of the world were made safe for the worlds seafaring vessels through a mix of genius, ingenuity, and perseverance. The story has a fascinalc(