EN
Gottfried Kirch (1639–1710) developed the screw micrometer to observe the occultation of ο Tauri by Saturn on January 7/17, 1679. The news about the instrument was not published immediately. The device was popularised by his calendar for 1696. The article presents preliminary findings concerning the dissemination of knowledge about this invention and responds to the claim that it was the most widely used micrometer in the German-speaking lands in the first half of the 18th century.