Zero circle

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Zero circle

A zero compass is a compass for drawing small circles with Indian ink . Its radius is adjustable from about 0.1 mm to 15 mm and the line width from about 0.1 mm to 1.0 mm. Among other things, it is part of a cartographer's drawing equipment and is used by him for border points , for example .

In 1874 Emil Oskar Richter invented the zero circle with a fixed axis and later the puncturing pen and thus standards in drawing material production all over the world. In addition to the zero circle, he also got the dotting pen patented by the Royal Saxon Patent Office . His company EO Richter & Co. GmbH was located in Chemnitz , but was partially destroyed in 1945. The main building on Melanchthonstrasse is a listed building because of the industrial architecture typical of the time and the sometimes lavish decor of an Art Nouveau staircase.