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Physical Sciences Collection - Surveying and Geodesy

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Theodolite

Catalogue number:
PH*316510

Dimensions:
telescope 2.375 aperture, 30 inches long; vertical circle 5.5 inches diameter; trunions 12.5 inches wide

Discussion:

This 30-inch theodolite was made by Troughton & Simms in London for the United States Coast Survey, probably in the late 1840s. Only the unusually short trunions, telescope, small vertical circle, and micrometer eyepiece remain; the standards, graduated horizontal circle, and tripod base are missing.

Ref: C. A. Schott, "Determination of the Astronomical Azimuth of a Direction," United States Coast Survey Annual Report (1866), Appendix No. 11.

Further Information:

Theodolite
Troughton & Simms

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