This circular slide rule consists of a silver-colored metal dial, 8-1/2" wide, mounted on a silver-colored metal disc. Three oblong holes on the base disc permit the reading of trigonometric scales on ...

IIIF provides researchers rich metadata and media viewing options for comparison of works across cultural heritage collections. Visit the IIIF page to learn more. In the late 19th and early 20th ...

While some (math-phobics) still may relish the simple beauty and non-threatening functionality of the abacus, there are those who have made the transition to more challenging computing gadgets—many ...

Around here we mostly enjoy slide rules. We even have our own collections including some cylindrical and circular ones. But [Mathologer] discusses a recent Reddit post that explains a circular slide ...

Torgoen has developed a pretty nifty watch, if you were born before the 50s and also had a stint at NASA. The Pilot Watch with Slide Rule features a circular slide rule that is “useful for units of ...

I like aviator styled watches. Some of them have a a dial on the outside that can be used to compute speed/fuel supply/Oil pressure, but I have never learned how to use these functions myself.