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Sextant

Catalogue number:
PH*309658

Inscriptions:
"Gambey B Paris" and "U.S.C. & G.S. No. 61"

Dimensions:
radius 7 inches

Discussion:
Henri Prudence Gambey (1787-1847) was the foremost maker of precision instruments in France in the first half of the 19th century, and many American physicists and geodesists used instruments from his shop. This sextant belonged to the U.S. Coast Survey (the case is stamped "U.S.C.S. No. 61"). Its silvered scale is graduated every 10 minutes from -5^o to +150^o and read by vernier with tangent screw and magnifier to 10 seconds of arc.

Ref: Deborah J. Warner, "Gambey’s American Customers," Rittenhouse 4 (1990): 65-78.

Further Information:

Sextant