Mappa.Mundi Magazine
Locus » Burt's Solar Compass Back »

Burt's Solar Compass

To run a north and south line with the solar compass. Set off the declination of the sun on the declination arc. Set off the latitude of the place (which may be determined by this instrument) on the latitude arc. Set the instrument over the station, level, and turn the sights in a north and south direction, approximately, by the needle. Turn the solar lens toward the sun, and bring the sun's image between the equatorial lines on the silvered plate. Allowance being made for refraction, the sights will then indicate a true north and south line.

from the book
Trigonometry Surveying and Navigation
by G.A. Wentworth, A.M.
Boston, U.S.A., and London
Ginn & Company, Publishers 1895

contact | about | site map | home T-O