Bausch & Lomb designed the Model microscope (No. 520) “in compliance with a generally expressed demand for a simple, low-priced and well-made instrument, which is adapted to every grade of work.” The basic stand with wooden case cost $25; with two objectives and camera lucida it cost $45. This example is of that sort. It is a compound monocular with coarse and fine focus, triple nosepiece, curved arm, circular revolving mechanical stage, trunnion, sub-stage apparatus, sub-stage mirror, and tri-leg base. The inscription on the stage reads “Bausch & Lomb / Optical Co.” The inscription on the arm reads “PAT. OCT. 3, 1876 / PAT. OCT. 13, 1885.
Bausch & Lomb customized this instrument for petrographic work according to the designs of George H. Williams, professor of mineralogy and inorganic chemistry at The Johns Hopkins University. To that end, there are Nicol prisms below the stage and in a double chambered box in the tube that serve as polarizer and analyzer. An opening in the nosepiece, just above the objective, would hold a Bertrand lens. In the 1890s, this form was termed an American Type microscope, model FLD6.
Ref: Bausch & Lomb, Microscopes, Microtomes, Apparatus for Photo-Micrography, and Bacteriology (Rochester, N.Y., 1896), pp. 46-47.
George H. Williams, “On a new Petrographical Microscope of American Manufacture,” American Journal of Science (Feb. 1888): 114-117.
Currently not on view
date made
Bausch & Lomb
place made
United States: New York, Rochester
Physical Description
metal (overall material)
glass (overall material)
brass (overall material)
overall: 37.3 cm x 14.5 cm x 20.5 cm; 14 11/16 in x 5 11/16 in x 8 1/16 in
ID Number
accession number
catalog number
Credit Line
Bausch & Lomb Optical Company
Science & Scientific Instruments
See more items in
Medicine and Science: Medicine
Science & Mathematics
Data Source
National Museum of American History


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