Surveyor's Transit

This is a Standard Precise Transit, Reconnaissance Model (#112-T), with a telescopic solar unit attached to one standard "as constructed for the Bureau of Land Management." It can be used for standard surveys, as well as for determining the solar meridian quickly and efficiently. Inscriptions read "W. & L. E. Gurley Troy, N.Y., U.S.A." and "461261."

Gurley produced its first example of this form in June 1946, basing it on specifications that the General Land Office (the predecessor of the Bureau of Land Management) had published in June 1944. The "Jos. C. Thoma” inscription on this example refers to a General Land Office surveyor who made substantial contributions to its design. Thoma’s widow transferred it to Clyde N. Eldridge, a surveyor and aerial photogrammetrist in Barnesville, Ga., and Eldridge’s brother donated it to the Smithsonian in his memory.

Ref: W. & L. E. Gurley, The Gurley Telescopic Solar Transit (Troy, N.Y., 1959).

W. & L. E. Gurley, Manual of Surveying Instruments (Troy, N.Y., 1951), p. 123.

“Joseph C. Thoma, Government Surveyor” Washington Post (Feb. 1, 1967), p. C6.

Currently not on view