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Physical Sciences Collection - Surveying and Geodesy

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Geologist's Compass - click to enlarge

Geologist's Compass - click to enlarge

Geologist's Compass - click to enlarge

Geologist's Compass - click to enlarge

Click photos to enlarge.

Geologist's Compass

Catalogue number:
PH*333652

Inscriptions:
"KEUFFEL & ESSER CO NEW YORK" and "U.S. INDIAN FOREST SERVICE. DEPT OF THE INTERIOR" and "1958"

Dimensions:
4 inches square

Discussion:

This is an aluminum compass with brass sights that, according to Keuffel & Esser, was designed for topographical work. The raised rim and beveled outer ring are graduated every degree and numbered every 10 degrees in quadrants from north and south. The northeast quadrant of the face has a variation scale that extends 27 degrees one way and 43 degrees the other, that is graduated to degrees, and that reads by folded vernier to 5 minutes. The southern half of the face is graduated to degrees, and equipped with a pendulum clinometer pivoted at the center. There are level vials on the SE and SW corners of the plate. The four beveled edges of the plate are graduated, one to inches and tenths, one to inches and eighths, and two as protractors. The back of the plate has a diagram showing the arrangement of township numbering. New, with ball joint and socket for mounting on a Jacob staff, this compass cost $25. The University of Missouri at Columbia donated it to the Smithsonian.

Ref: Keuffel & Esser, Catalogue (New York, 1913), p. 420.

Further Information:

Compass (pocket)
Keuffel & Esser

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