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Physical Sciences Collection - Surveying and Geodesy

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Surveyor's Vernier Compass - click to enlarge

Surveyor's Vernier Compass - click to enlarge

Click photos to enlarge.

Surveyor's Vernier Compass

Catalogue number:
1989.0403.10

Inscriptions:
"T. F. RANDOLPH CINCINNATI, O."and "1332" and "PATENTED JUNE 24 ‘79"

Dimensions:
needle 6 inches; telescope 7 inches

Discussion:

T. F. Randolph termed this a Patent Vernier Telescope Compass, referring to his 1879 patent (#216,769) for an Improvement in Surveying-Instruments. The raised rim is silvered and graduated to single minutes. The variation arc, located on the compass face, extends ± 20 degrees and reads by double vernier to single minutes. There are two level vials on the face. The telescope assembly is provided with two obviously later additions: a level vial marked "G. F. RICHARDSON, ATHOL, MASS." and a vertical arc marked "G. F. Richardson, Athol, Mass." and "PATENTED Aug. 16, 188x."

Ref: T. F. Randolph, Illustrated Catalogue and Price List (Cincinnati, 1892), p. 2.

Further Information:

Randolph
Compass

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