This circular dividing engine fits on a table. It has an iron, T-shaped base with three holes for attaching the engine to a base. A mechanism with lever handle and tracer arm, a microscope on a ...

IIIF provides researchers rich metadata and media viewing options for comparison of works across cultural heritage collections. Visit the IIIF page to learn more. Dividing engines scribed the fine ...

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in ...