Calcul du temps de Pose en Photographie
Paris: Gauthier-Villars et Files and G. Masson n.d. [c1896]. 214, [32-ads] pages. Publisher's light brown cloth with black printing. 4 1/2 x 7 3/8 inches. Advertisements in rear are heavily browned and brittle (several with old cellotape repairs and with some tearing/chipping). Otherwise textblock has only light browning. Ex-library Franklin Institute with spine label, rear pocket (removed affecting rear pastedown advertisements), and several embossed owner marks. Front pastedown endpaper advertisements. A sound reading or reference copy. Good. Cloth. 
The title translates roughly to: "Time Calculation Pose in Photography". Part of the "Encyclopedie Scientifique Des Aide-Memoire" series. Dated based on advertisements in the rear up through 1896. Chapters address optical factors, chemical factors, sources of light, factors affecting the sitter, etc. Today it is simply point and shoot. Back then it was important to have a handle on your equipment, chemicals, and environment to properly photograph subjects. Scarce, with just over a dozen copies noted in OCLC.