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Rude Star Finder (1921)

Catalogue number:

"THE MARINER’S PRACTICAL STAR FINDER / A SIMPLE MEANS FOR IDENTIFYING AND SPOTTING STARS AND PLANETS. / NO COMPASS BEARINGS NECESSARY / G. T. RUDE Hydrographic and Geodetic Engineer / U.S. Coast and Geodetic Survey / Patents applied for / Price $12.00"

diameter 14 inches

The Rude Star Finder lets a navigator identify a star from its altitude above the horizon. It consists of planispheric maps of the northern and southern skies, the rims of which are graduated to two minutes of time. Each planisphere has a celluloid meridian arm for determining the declination of stars, with a slide that can be adjusted for the latitude of the observer. There are in addition eleven transparent celluloid altitude-azimuth templates for use at different latitudes up to 66o north and south–that is, over the greater part of the navigable waters of the globe; a set of pins for marking the positions of the planets; an instruction brochure; and a cardboard case.

Gilbert Rude applied for a patent for this device in December 1920. This example was made before the patent issued in December 1921. Rude donated it to the Smithsonian in 1957.

Ref: G. T. Rude, "Star Finder and Identifier," U.S. patent #1,401,446.

Further Information:

Star Finder