Smithsonian - National Museum of American History, Behring Center

 
Physical Sciences Collection - Surveying and Geodesy

Browse Makers | Browse Instruments | Index

Back
 

Geodetic Transit - click to enlarge

Geodetic Transit - click to enlarge

Click photos to enlarge.

Geodetic Transit

Catalogue number:
PH*328709

Inscriptions:
"No 145 EDWD KAHLER WASHINGTON, D.C."

Dimensions:
telescope 30 inches long, 2.75 inches aperture; vertical circle 10 inches diameter

Discussion:

This transit was made in 1877 for the new John C. Green Astronomical Observatory at Princeton University, and resembles the instruments that Stackpole & Brother had made for the 1874 transit of Venus. It has a "broken" telescope that is viewed through one end of the horizontal axis, a micrometer eyepiece, a cast iron base, and a mechanism that is used to lift and reverse the telescope. The vertical circle is silvered, graduated to 10 minutes, and read by opposite verniers to 10 seconds. Edward Kahler (1832-1890) was born in Germany, and is listed in Washington, D.C. directories from 1869. Charles A. Young, the newly appointed astronomer at Princeton, carried on a lengthy correspondence with Kahler, repeatedly modifying the design even as the instrument was being built.

Ref: Charles A. Young papers, Princeton University Archives.

Further Information:

Geodetic Transit
Stackpole

Back