Black and white albertype in the frontispiece of C.F. Prentice's, "Dioptric formulae for combined cylindrical lenses." As described in his book, the image features, "Dr. Swan M. Burnett's models, demonstrative of cylindrical refraction, as contructed, by the author, in accordance with the "Formulae for congeneric cylindrical lenses."".
Copyright:
The National Library of Medicine believes this item to be in the public domain. (More information)