pocket sextant
Date1797
Inventory Number0062
ClassificationSextant
Subject
Maker
W. & S. Jones
fl. 1791 - 1859
Cultural Region
Place of Origin
Dimensions3.8 x 8.6 x 8.6 cm (1 1/2 x 3 3/8 x 3 3/8 in.)
Material
Bibliography
DescriptionThis is a standard pocket sextant, with the sextant armature housed in a cylindrical brass box. There is a mirror, half-silvered horizon glass, and one sun shade of dark red glass. The sun shade is moved into position by a pin on the front face of the housing. The peep hole has a cover operated by a pin on the outside of the cylinder. The index arm is moved by rackwork and knurled thumb screw. It has a left-aligned vernier divided 0-30. The scale is engraved directly on the brass face of the housing and is divided from -5° to 140° every 30'. With the vernier it reads to 1'. The instrument is signed above the divided scale.
The cover of the sextant is pressure-fit and cylindrical. The interior is engraved with a table of four columns:
Mul. Angle. Angle. Div.
1 45° 00' 45° 00' 1
2 63 26 26 34 2
3 71 34 18 26 3
4 75 58 14 02 4
5 78 41 11 19 5
6 80 32 9 28 6
8 82 52 7 08 8
10 84 17 5 43 10
The exterior of the cover is blank, except for the remnants of an earlier inventory number (9 21), which was stamped twice in black ink, and the current inventory (62) painted in red.
The edges of the cylindrical case and cover are finely knurled.
The cover of the sextant is pressure-fit and cylindrical. The interior is engraved with a table of four columns:
Mul. Angle. Angle. Div.
1 45° 00' 45° 00' 1
2 63 26 26 34 2
3 71 34 18 26 3
4 75 58 14 02 4
5 78 41 11 19 5
6 80 32 9 28 6
8 82 52 7 08 8
10 84 17 5 43 10
The exterior of the cover is blank, except for the remnants of an earlier inventory number (9 21), which was stamped twice in black ink, and the current inventory (62) painted in red.
The edges of the cylindrical case and cover are finely knurled.
SignedW. & S. JONES. / Holborn London.
Curatorial RemarksFound in 1949 in a second-floor cabinet in Jefferson Lab.
FunctionThe pocket sextant was a small, portable version of the maritime sextant housed in a durable, cylindrical brass case, which also served as its handle. It was used for measuring angles and favored by surveyors for its rugged portability.
ProvenanceTransferred to CHSI from Jefferson Physical Laboratory, May 1948.
Historical AttributesW. & S. Jones shipped this pocket sextant to Harvard onboard the Eliza on 11 March 1797 along with 37 other instruments. The invoice, preserved in the University Archives, describes this instrument as "a new pocket reflecting brass sextant £2.16.0."
Date: 1890-1930
Object number: RS0501
Date: late 19th-early 20th Century
Object number: RS0168
Western Electric Company
Date: 1900-1930
Object number: RS0196
Date: 1890-1930
Object number: RS0505
Sylvania
Date: late 19th-early 20th Century
Accessories: brown cardboard box, with handwritten note, "345 on 35"
Object number: RS0369
Date: 1890-1930
Object number: RS0174
Date: late 19th-early 20th Century
Object number: RS0294
