1. A treatise on simple and compound ophthalmic lenses: their refraction and dioptric formulae, including tables of crossed cylinders and their sphero-cylindrical equivalents Author(s): Prentice, Charles F. (Charles Frederick), 1854- Publication: New York : J. Prentice & Son, opticians, [c1886] Subject(s): EyeglassesRefraction, Ocular