This is a substantial compound monocular with coarse and fine focus, trunnion, mechanical stage, sub-stage mount, and accessories for petrographic work. The wooden case is lined with purple silk and velour. The “NACHET / 17 Rue St. Séverin / Paris” inscription refers to an important French optical firm that was begun by Camille Sebastien Nachet in 1839. The firm became Nachet et Fils around mid-century, moved to this address in the early 1860s, and began making petrographic microscopes around 1880.
This belonged to Kenneth E. Lohman (b. 1897), a geologist with the U.S. Geological Survey who was particularly interested in diatoms.
Ref: Albert Johannsen, Manual of Petrographic
Currently not on view
Object Name
date made
after 1890
Nachet et Fils
Physical Description
brass (overall material)
glass (overall material)
case: 6 1/2 in x 19 1/2 in x 11 1/2 in; 16.51 cm x 49.53 cm x 29.21 cm
overall: 14 7/8 in x 4 1/4 in x 6 1/8 in; 37.7825 cm x 10.795 cm x 15.5575 cm
place made
France: Île-de-France, Paris
ID Number
catalog number
accession number
Science & Mathematics
Science & Scientific Instruments
See more items in
Medicine and Science: Medicine
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
Kenneth E. Lohman
Additional Media

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