This is a Van Heurck Model B compound monocular. William Watson & Sons designed the form in 1891 at the suggestion of Henri van Heurck, a noted Belgian microscopist, and sold it as suitable for photography and high-power work. It has coarse and fine adjustment, mechanical stage with centering screws, sub-stage mirror, tripod foot, wooden case, and several eyepieces and objectives. The inscription reads “W. WATSON & SONS / 313 HIGH HOLBORN / LONDON” and “3678.”
Julius F. Stone saw the Watson display at the Columbian Exposition held in Chicago in 1893 and bought this example soon thereafter. In 1943 he gave it to Thomas Henry Langlois, a biologist who would become director of the Franz Theodore Stone Laboratory on Gibraltar Island in Lake Erie. Dr. Langlois’ daughter, and her husband, gave it to the Smithsonian in 1975.
Ref: W. Watson & Sons, An Illustrated Catalogue of Microscopes (London, 1893), pp. 18-25.
Currently not on view
Object Name
date made
ca 1893
Watson, William
case: 15 3/4 in x 11 1/2 in x 11 1/8 in; 40.005 cm x 29.21 cm x 28.2575 cm
microscopes: 13 in x 9 in x 10 1/4 in; 33.02 cm x 22.86 cm x 26.035 cm
place made
United Kingdom: England, London
ID Number
accession number
catalog number
serial number
Science & Scientific Instruments
Science & Mathematics
See more items in
Medicine and Science: Medicine
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
Mr. & Mrs. Howard Conklin
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