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Sextant

Catalogue number:
1989.0010.01

Inscriptions:
"Riggs Brothers, Philadelphia"

Dimensions:
radius 7 inches

Discussion:
This sextant, which was probably made in England, has a double brass frame of the sort introduced by Edward Troughton in London in 1788. The silvered scale is graduated every 10 minutes from -5^o to +155^o and read by vernier with tangent screw and swinging magnifier to 10 seconds of arc. Riggs & Brothers signature began to be used in 1865.

Further Information:

Riggs
Sextant