- A spherometer is a device used primarily for measuring the curvature of objects such as lenses and curved mirrors. For further information about spherometers, see object MA.315739.
- This spherometer was constructed by Allen L. Colton (1857-1950) while he was a student at the University of Michigan. He worked for the US Weather Bureau in the late 1800s, followed by five years as assistant astronomer at the Lick Observatory where he was a physicist, photographer, and instrument maker. Early in the 20th century, he joined the faculty at the University of Wisconsin as a physics instructor. This item was donated to the Smithsonian in Colton's memory by his cousin.
- To improve accuracy, a magnifying lever is mounted on the top of the micrometer disc. The two small arms would have pointed to a secondary scale that arched over the top of the device, but is now missing.
- Barton, Albert (ed.), The Wisconsin Alumni Magazine 5, no. 3 (December 1903): 82. http://www.digicoll.library.wisc.edu
- Currently not on view
- Object Name
- date made
- ca 1877
- Colton, Allen L.
- place made
- United States: Michigan, Ann Arbor
- Physical Description
- wood (overall material)
- glass (overall material)
- brass (overall material)
- overall: 14.5 cm x 14.5 cm x 14.5 cm; 5 23/32 in x 5 23/32 in x 5 23/32 in
- ID Number
- accession number
- catalog number
- Credit Line
- Gift of Martha Taylor
- Data Source
- National Museum of American History
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