Prismatic Compass

Prismatic Compass

Compass surveying is a type of surveying in which the directions of surveying lines are determined with a magnetic compass, and the length of the surveying lines are measured with a chain or tape or laser range finder.
Prismatic compass is given to it because it essentially consists of a prism which is used for taking observations more accurately.
Compass is generally used to run a traverse line compass calculates bearings of lines with respect to magnetic needle and included angles can then be calculated using easy formulas in case of anti-clockwise and clockwise traverse respectively for each survey line in the traverse, surveyors take two bearings that is for bearing and back bearing which should exactly 180°.