A proportional compass (or dividing compass ) is a drawing device that allows you to build a segment proportional to a given segment in a given proportion .
The dividing compass accelerates the work, making it possible to take the dimensions according to the drawing and directly, without counting, get enlarged or reduced in the right scale. Descriptions of the dividing compass are often given as an illustration when studying similar figures in geometry textbooks [1] [2] .
Device
The necessary proportion is established by means of a movable link that carries the compass axis. The most common proportions, in particular π and the relations of the parties to the right 
Notes
- ↑ A.P. Kiselev . Elementary geometry / edited by N. A. Glagolev . - 1938.
- ↑ A. F. Malinin and F. I. Egorov . A course in visual geometry and a collection of geometric problems for county schools . - M .: br. Salaevs, 1873.