Abel Niépce de Saint-Victor

French photographic inventor, an army lieutenant and cousin of Nicéphore Niépce, he first experimented in 1847 with negatives made with albumen on glass, a method subsequently used by the Langenheim brothers for their lantern slides. At his laboratory near Paris, Niépce de Saint-Victor worked on the fixation of natural photographic colour as well as the perfection of his cousin's heliographic process for photomechanical printing. His method of photomechanical printing, called heliogravure, was published in 1856 in Traité pratique de gravure héliographique. In the 1850s he also published frequently in La Lumière. He died on 7 April 1870 in Paris at age 64.