photography related industry in Rochester (New York)
American Camera | Bausch & Lomb | Blair | Century | Crown Optical Co. | Elgeet | Folmer & Schwing | Gassner and Marx | Graflex | Gundlach | Ilex | JML | Kodak | Milburn | Monroe | PMC | Ray | Reichenbach, Morey and Will | Rochester Camera and Supply Co. | Rochester Optical Co. | Seneca | Sunart | Walker | Wollensak
and in Rochester (Minnesota)
external links - Rudolf Kingslake's
"Optical industry in Rochester (N.Y.)"

Gassner and Marx was founded by Benjamin Marx, James Rothschild and Henry Gassner. They manufactured the Day Plate Camera on which they had received a patent in 1898. It had to be loaded with a set of 3¼ x 4¼-inch glass plates which were packaged in a strip of black paper, thus allowing daylight loading of the camera.