Antique 19th-century Darlot portrait Petzval lens from the collection of Otto Berg, size 1-2, 2.25″ diameter, 7″ focus, engraved on the barrel, "A. T. Thompson & Co., Importers, Boston," and marked on the lenses, "12 3044 2866 Darlot, Paris." In very good to fine condition, with general overall wear; the rack and pinion mechanism works smoothly. A handsome and well-crafted lens, perhaps used by Berg in some of his optical experiments.
From the collection of Dr. Otto Berg.
