Solar Compasses

SC 1, Burt's Improved Solar Compass, Wm. J. Young, maker, Philadelphia, PA, c. 1852.

The solar compass is one of the most important instruments in American surveying history, and was specifically designed for surveying the U.S. public lands. It was invented by William A. Burt in 1836 and determines the true-north direction from the sun's position in the sky.

This instrument is 14.2" long and has 7.1" high sight vanes. It also has a telescopic sight to use instead of the vanes. The 7.3" telescope has a full vertical circle and vernier with no set clamp. There is a counterweight for attaching to the opposite arm when the telescopic sight is used. The latitude and declination arcs have slow-motion adjustment screws which are possibly later modifications. The eyepiece arm is inscribed "Wm. J. Young, Maker, Philadelphia." The opposite arm is inscribed "Burts Patent."

The 1852 dating corresponds to Robert Miller's article appearing in Rittenhouse, 5:1, Nov. 1990, pps. 21-24. For additional information on the solar compass see They Left Their Mark by John S. Burt, (Landmark Enterprises, Rancho Cordova, CA, 1986).

Take a 360 degree look at this instrument by clicking on the pictures below (requires Free QuickTime Plug-In):

You can move the instruments around by the using the left and right arrow keys. 

SC 2, Burt's Improved Solar Compass w/Clamp-on Telescope, W. & L.E. Gurley Co., maker, Troy, NY, c. 1894.

This  was  reportedly owned owned by surveyor John C. Bliss in Nevada.   The Bliss family was prominent in the Carson City - Lake Tahoe area, noting Bliss State Park at the lake.

The instrument has a medium-toned brass color. It is 18" wide with the telescope horizontal, and 13º" high. The telescope is 8 3/4" long and has a patent date of July 9, 1878. The sighting vanes are each 7 3/4" high. There is a box compass with a 3½" needle. The horizontal circle is 5½" in diameter, and has a single one-minute vernier. The instrument has a detachable leveling base. Inside the instrument is scratched "June 03 v." The compass is complete with case and original tripod.

This solar compass is pictured on the back cover of the 1980 illustrated price guide, and also on page 11 of Chaining the Land.

Take a 360 degree look at this instrument by clicking on the pictures below (requires Free QuickTime Plug-In):