Smithsonian - National Museum of American History, Behring Center

 
Physical Sciences Collection - Surveying and Geodesy

Browse Makers | Browse Instruments | Index

Back
 

Transit - click to enlarge

Click photos to enlarge.

Transit

Catalogue number:
PH*309850

Inscriptions:
"Stackpole & Brother, New York 939"

Dimensions:
height 8.5 inches; horizontal circle 5.5 inches diameter; telescope 13 inches long

Discussion:

A. J. Kirby of Westchester County, New York, acquired this instrument around 1870 and used it for about 50 years. His son donated it to the Smithsonian in 1930. The instrument is unusual in several ways: the telescope is transit mounted but too long to transit, and an adjustable strut at the objective end holds the telescope at a fixed angle of elevation. The horizontal circle is silvered, graduated to 20 minutes, and read by opposite verniers to 20 seconds. There is a magnetic compass in the center of the circle that is suitable only for rough orientation, and a hanging level below the telescope.

F. E. Brandis, who was working for Stackpole at the time that this instrument was made, would later incorporate some of its features--most notably the long transit-mounted telescope and the adjustable strut--in what he called his Improved City Transit.

Further Information:

Theodolite
Stackpole

Back