The Probert Encyclopaedia of Science & Technology

COMPASSES

Compasses, also known as a pair of compasses, are a mathematical instrument used for the describing of circles, measuring lines, etc. They consist simply of two pointed legs, movable on a joint or pivot, and are used for measuring and transferring distances. For describing circles the lower end of one of the legs is removed and its place supplied by a holder for a pencil or pen.
Research Compasses