There was a time when electronic calculators did not yet exist. This did not stop us from doing complicated things, like going to the moon, figuring out the double helix, or designing the Boeing 747. In those days, when we needed to compute things, we used slide rules which are marvelous and beautiful instruments!

There are many pages about slide rules on the web, and you can still buy brand new slide rules (40 years old but never used, and still in their factory supplied box) in various places. The purpose of this particular and quite idiosyncratic slide rule page is to describe common scales used on slide rules, and the kind of mathematical expressions that could be evaluated with those scales.

Greetings! This site contains scans and descriptions of my collection of slide rules, along with several pages of (hopefully) useful background information. I haven't been actively collecting new rules for several years now, but I have kept the site up as a resource for others.

This self-guided course gives numeric examples of the basic calculations that a slide rule can do. Just follow the step-by-step instructions and you will be amazed by the power and versatility of the venerable Slipstick. Click on any of the images below to get a large, unmarked, blowup of each slide rule as shown in the problem.

The site can also be downloaded as a PDF for use as a textbook.