Gurley Transit

Description
Gurley described this as a Surveyor's Transit with two verniers to the horizontal limb. The horizontal and vertical circles are silvered, graduated every 30 minutes of arc, and read by verniers to single minutes. There is a clamp and tangent to the telescope axis. A variation scale on the face of the compass extends 30 degrees either way; the double folded vernier reads to single minutes. The transit is easily detached from the leveling head, and the two are stored separately in the box. Since the "W. & L. E. Gurley, Troy, N.Y." signature was engraved by hand, this transit was made between 1852, when Gurley began in business, and 1876, when Gurley's new engraving machine was up and running.
Ref: W. & L. E. Gurley, Manual of the Principal Instruments used in American Engineering and Surveying (Troy, N.Y., 1871).
Location
Currently not on view
maker
W. & L. E. Gurley
place made
United States: New York, Troy
Measurements
overall: 12 in; 30.48 cm
horizontal circle: 6 3/4 in; 17.145 cm
needle: 5 in; 12.7 cm
vertical circle: 4 1/4 in; 10.795 cm
telescope: 11 in; 27.94 cm
hanging level: 5 1/2 in; 13.97 cm
overall in case: 13 in; 33.02 cm
ID Number
1982.0701.07
accession number
1982.0701
catalog number
1982.0701.07
Credit Line
UOP Inc.
See more items in
Medicine and Science: Physical Sciences
Measuring & Mapping
Surveying and Geodesy
Data Source
National Museum of American History, Kenneth E. Behring Center

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