Burt's solar compass or astronomical compass/sun compass is a surveying instrument that makes use of the Sun's direction instead of magnetism. William Austin Burt invented his solar compass in 1835. The solar compass works on the principle that the direction to the Sun at a specified time can be calculated if the position of the observer on the surface of the Earth is known, to a similar precision. The direction can be described in terms of the angle of the Sun relative to the axis of rotation of the planet.
William Austin Burt's solar compass
Line illustration of his solar compass from 1836 US patent documentation
Burt's solar compass axes
Image: Coles Universal Sun Compass 6314c
Surveying or land surveying is the technique, profession, art, and science of determining the terrestrial two-dimensional or three-dimensional positions of points and the distances and angles between them. These points are usually on the surface of the Earth, and they are often used to establish maps and boundaries for ownership, locations, such as the designed positions of structural components for construction or the surface location of subsurface features, or other purposes required by government or civil law, such as property sales.
A surveyor using a total station
A student using a theodolite in field
Table of Surveying, 1728 Cyclopaedia
A railroad surveying party at Russel's Tank, Arizona in the 1860s