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Physical Sciences Collection - Surveying and Geodesy

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Surveyor's Vernier Compass - click to enlarge

Surveyor's Vernier Compass - click to enlarge

Surveyor's Vernier Compass - click to enlarge

Click photos to enlarge.

Surveyor's Vernier Compass

Catalogue number:
PH*333650

Inscriptions:
"Mahn & Co. St. Louis, Mo."

Dimensions:
length 15.5 inches; needle 5.125 inches

Discussion:
This compass dates from the period 1891-1906, when Herman Mahn was in business in St. Louis, trading as Mahn & Co. It has a variation arc on the south arm that extends 24 degrees either way; the vernier is moved by a tangent screw on the south arm, and reads to 2 minutes. There is an outkeeper on the south arm, and there are two level vials on the north arm. It belonged to the University of Missouri at Columbia.

Further Information:

Surveyor's Compass

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