B65-482 SURVEYING INSTRUMENT. Hale Patent. The instrument patented in 1885 by John Hale of Scranton was designed for use in mines, and intended to avoid the need for magnetic compasses which would be influenced by the presence of ore deposits. The patent drawings show a semi-circular instrument, with sights in the center and mounted on an adjustable vernier arm. Examples conforming to the patent drawing are known to exist. The one, however, has a complete circle, with a compass with 4-1/4" needle in the center. It has the same movable vernier arm, but also has crossed levels and a Jacobs staff so it can be used as a more traditional surveying compass. The compass dial has "J. Hale Maker" and the patent date at north. In its original box, worn but complete noting a few chips, that contains two separate sets of sighting vanes, one set fixed and one folding. Apparently Mr. Hale found that his device would be more marketable if configured for use as a traditional compass, but it can't have been that marketable as this is the only one we've ever seen. In immaculate working condition. From the collection of Chuck Morgan. Fine 3000-6000