W. & L. E. Gurley termed this a Surveyor's Transit with two verniers to the horizontal limb. The inscription on this example reads "W. & L. E. Gurley, Troy, N.Y. 9296." The horizontal circle is silvered, graduated every 30 minutes of arc, and read by opposite verniers to single minutes. There is a clamp and a tangent to the telescope axis. With tripod, this transit sold for $148. The serial number indicates that it was the 296th instrument that Gurley made in 1909.
Ref: W. & L. E. Gurley, Manual of the Principal Instruments used in American Engineering and Surveying (Troy, N.Y., 1909), pp. 43-46 and 272.
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