General Information

Serial #

65402

Part Number

1

Total Parts

7

AKA

N/A

Patents

N/A

General Description

Frame & arm made from brass/glass lenses and mirrors/wooden handle and carrying case/plastic telescope/leather neck strap/frame& arm painted black/handle painted black/case stained brown and varnished.

Dimensions

Note: These reflect the general size for storage and are not necessarily representative of the object's true dimensions.

Length

34.1 cm

Width

30.5 cm

Height

65.5 cm

Thickness

N/A

Weight

N/A

Diameter

N/A

Volume

N/A

Lexicon

Group

Exploration and Survey

Category

Measurement-angles

Sub-Category

N/A

Manufacturer

AKA

Kelvin Hughes

Country

England

State/Province

Unknown

City

Unknown

Context

Country

Unknown

State/Province

Unknown

Period

Unknown

Canada

Acquired from the NRC in 1985.

Function

Vernier sextant; used by navigators to determine their position at sea. A series of reflecting mirrors are arranged so that a celestial body can be lined up with the horizon, and the longitude and latitude are measured.

Technical

Manufactured by Kelvin & Hughes Ltd. Arc goes from -5 degrees to 150 degrees, and vernier reads to 20 units. Sextants replaced older methods of measuring angles because more precision could be obtained due to the star being measured relative to the horizon, and not the instrument, which was used previously. Serial number 65402.

Area Notes

Unknown

Details

Markings

Mfr's trademark 'KH' superimposed over a red arrow appears on sliding arm of sextant./ 'MADE IN GREAT BRITAIN', 'KELVIN & HUGHES LTD.', 'SURVEY', and 'SER. NO. 65402' incised on top edge of rule/ Mfr's specifications label and cleaning instructions appear side lid: Off-white rectangular label, protected by plastic window, affixed inside lid of box. Two seated mermaids appear in upper right and left corners; rope-like motif surrounds text, interrupted by decorative seahorse figure on either side, at mid-point of border./ Text:: ‘KELVIN/ &/ HUGES/ LIMITED/ THE SEXTANT NO. 65402./ named Kelvin & Hughes Ltd./ of 6" radius & reading to 1'/ has been examined & found satisfactory/ The following corrections should be applied: –/ Angle 30 60 90 120 / Correction 0' 0' 0' 0'/ The shades and mirrors are satisfactory/ Telescope data: –/ magnification/ 5x/ Angle of Field of View/ 3.5 / Effective Aperture 1.75"/ The definition is satisfactory/ Date 1/11/57. Signed [illegible]'./ Label encased in plastic screwed to inside lower edge of lid bears the following info.: ‘IMPORTANT/ (1) Keep the bearing grooves at the edge of the arc/ lubricated sparingly at regular intervals with the/ special oil provided./ (2) The arc and micrometer teeth must be kept/ clean in order to prevent any stiffness developing/ in the index bar movement./ (3) Rub mirrors very lightly when cleaning, no pressure should be applied.'/ '6431', '65', and 'SEXTANT' handwritten on case./ BOX: Off-white rectangular label, protected by plastic window, affixed inside lid of box. Two seated mermaids appear in upper right and left corners; rope-like motif surrounds text, interrupted by decorative seahorse figure on either side, at mid-point of border. Text: ‘KELVIN/ &/ HUGES/ LIMITED/ THE SEXTANT NO. 65402./ named Kelvin & Hughes Ltd./ of 6" radius & reading to 1'/ has been examined & found satisfactory/ The following corrections should be applied: –/ Angle 30 60 90 120 / Correction 0' 0' 0' 0'/ The shades and mirrors are satisfactory/ Telescope data: –/ magnification/ 5x/ Angle of Field of View/ 3.5 / Effective Aperture 1.75"/ The definition is satisfactory/ Date 1/11/57. Signed [illegible]'./ Label encased in plastic screwed to inside lower edge of lid bears the following info.: ‘IMPORTANT/ (1) Keep the bearing grooves at the edge of the arc/ lubricated sparingly at regular intervals with the/ special oil provided./ (2) The arc and micrometer teeth must be kept/ clean in order to prevent any stiffness developing/ in the index bar movement./ (3) Rub mirrors very lightly when cleaning, no pressure should be applied.'

Missing

Unknown From CA of 08/11/1995 by Tony Missio: Undetermined

Finish

Unknown

Decoration

N/A