Gurley Transit

This is marked "W. & L. E. Gurley, Troy, N.Y." Gurley described it 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. A clamp and tangent to the telescope axis are present, as well as a gradienter attachment for determining gradients, distances, and differences of level. A variation scale on the face of the compass extends 35 degrees either way; the vernier reads to single minutes. The telescope has a fitting for a solar attachment. It was made after 1886, when Gurley introduced the bent standards, and before the introduction of serial numbers in 1908.
Ref: W. & L. E. Gurley, Manual of the Principal Instruments used in American Engineering and Surveying (Troy, N.Y., 1904), pp. 33-36 and 259.
Currently not on view
Object Name
date made
W. & L. E. Gurley
overall: 15 in; 38.1 cm
horizontal circle: 7 in; 17.78 cm
needle: 4 1/2 in; 11.43 cm
vertical circle: 4 1/2 in; 11.43 cm
telescope: 11 1/2 in; 29.21 cm
hanging level: 6 in; 15.24 cm
place made
United States: New York, Troy
ID Number
accession number
catalog number
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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