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Sextant

Catalogue number:
PH*335211

Inscriptions:
"Stackpole & Brother New York" and "2258"

Dimensions:
radius 6 inches

Discussion:
This sextant belonged to Columbia University in New York and dates from around 1880. The frame is brass. The silvered scale is graduated every 10 minutes from -5^o to +180^o and read by vernier with tangent screw and swinging magnifier to 10 seconds of arc.

Ref: Deborah J. Warner, "American Octants and Sextants: The Early Years," Rittenhouse 3 (1989): 86-112, on 108-109.

Further Information:

Stackpole
Sextant