How to make pictures : easy lessons for the amateur photographer (1887)
Price, Henry Clay · New York : Scovill Manufacturing Co. · leaf 86
gs. 1 and 6.) The edge of the case fits in an angular groove cut in the inside surface of the back near its edge, for the purpose of making a light-tight joint, when the case is pressed home. The light metal frame supporting the working parts is held to the removable back by four spring bolts, one… … elevated or thrown back, the opposite set of bolts forming a pivot or hinge. In this position the back forms a base to sup¬ port the frame when placed upright. When the frame is dropped down, the spring bolts are again drawn inward, and in shooting back lock the frame to the back. Thus either end…
Photography
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.
