Troughton & Simms Geodetic Transit

This instrument, which the U. S. War Department transferred to the Smithsonian in 1933, was probably used by the Army Topographical Engineers.It is marked "Troughton & Simms, London 2" and was made perhaps as early as the 1840s. It has a double-cone horizontal axis, a lamp for illuminating this axis, a large striding level, a small vertical circle at one end of the horizontal axis, and an iron base.
Currently not on view
Troughton and Simms
place made
United Kingdom: England, London
telescope: 31 in; 78.74 cm
aperture: 2 3/8 in; 6.0325 cm
striding level: 18 in; 45.72 cm
vertical circle: 5 in; 12.7 cm
ID Number
accession number
catalog number
Credit Line
War Department
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Medicine and Science: Physical Sciences
Measuring & Mapping
Surveying and Geodesy
Data Source
National Museum of American History