Sextants and accessories

Title

Sextants and accessories

Description

The "old astronomy" was dominated by the precise measurement of the positions of the stars and the determination of time. At Illinois, astronomy was first taught as part of the Civil Engineering department helping to develop the engineers' surveying skills. Specialized telescopes and procedures were developed for this purpose. As the "new astronomy" of astrophysics began to develop, positional astronomy was taught less and less. The one exception was the need for navigation by military ships and airplanes. In 1918 a Navigation course was offered for air service men. The course continued after WWI and was advertised as a course of interest to engineers and those thinking of working on merchant ships. This collection consists of sextants and other accessories such as artificial horizons that were used in positional astronomy, surveying, and navigation.

Contributor

Department of Astronomy

Items in the Sextants and accessories Collection

Sextant and artificial horizon
Wood, metal, brass

Hinged box with lock, missing handle, inside lined with green felt, green paper Newton label. University tag crossed out in pen.

Sextant valued in 1908 estimated $50. Engraved on arc “Newton + Co 3 Fleet Street London.”…

Sextant and artificial horizon
Wood, metal, glass

Metal black frame with wood handle and silver scale. Horizon mirror is broken, includes 4 index filters, 3 horizon filters, 3 brass telescopes, 2 lens caps, wooden handle, 6” radius on scale, maker and model 4323 marked on…

Double frame bridge sextant
Wood, metal, glass

Fitted keystone wood box with hinged lid and two hook latches. Black metal frame with brass screws, silver scale and wood handle. Includes 3 black painted telescopes, 1 eyepiece cover, 8-½ inch radius, eyepiece to read…

Marine sextant
In the Keuffel & Esser catalog , model 5224D on page 410, cost, $80. Paper label includes model 5224D and serial number 42046. Gun-metal, measuring angles up to 130 degrees, radius 6-in graduated on solid silver to 20 minutes, vernier to 30 seconds.…

Reflection horizon
Black glass ground plane surface, 3 3/8 diameter, 3 leveling screws, fine graduated adjustable spirit level, and mahogany case.

In the 1913 Keuffel & Esser catalog (page 413) the reflecting horizon cost $16. The reflecting horizon is an…

Compass
There are three Astro Compass Mark II, in green wooden boxes with canvas handles. It can be pointed at a known star, including the sun, and used to indicate true north. Manual included.

Bubble sextant
Wood, metal alloy, plastic

Marked property Air Force-US Navy, type A-10A. Probably WW II era. Blackened aluminum casting, containing clockwork, lenses, mirrors, buddle level, and rubber eyecup. In fitted wooden box. A small rugged aircraft…

Sextant and artificial horizon
Wood, metal, glass

Sextant:
Wooden box with hinged lid, inside includes Keuffel & Esser paper label and “obs 15” mark. Sextant matched with artificial horizon A214.2.

Black metal frame, wood handle, silver scale, maker marked on index…

Sextant
Wood, metal, glass

Black aluminum frame, wood handle, one telescope, no filters, micrometer wheel on vernier scale, arc is black with white engraved scale from 0 to 140. Marked on index arm “U.S. Navy Bureau of Ships ETS Sextant, Mark 2 Mod 0…

Sextant
Wood, metal, glass

Wood box, 9 7/8 x 9 7/8 x 5 ½ inch, with hinged lid, two hook latches and metal handle. Maker’s laminated paper label and university ID tag on inside. While the last inspection date on this sextant is 1939, the last sextant…