Continue Following on Substack, including an introduction to this site.
Collection Photos
A chronological look at the slide rule collection		 Returning to the site?
New Rules!
Rule Makers
The collection, organized by manufacturers		 Special Groupings

oldest, youngest,
most scales,
specialty slide rules, …
A Searchable Table of the entire collection
A Data Sheet for each rule Reference Material

Site Tips
New to slide rules? What is a slide rule? What is a logarithm? How do you use a slide rule? What do all the scales mean?
Go to the Introduction NEW! – Slide Rules for sale
Vignettes 44 blog-like articles and stories about slide rules, calculations, and collecting
New material and updates to many of the vignettes can be found at our Substack page.

Welcome!

This DataFrame-driven web site presents a personal collection of slide rules as well as other useful information about slide rules, their operation and use. Click the arrows (> and <) on each page or use your keyboard’s arrow keys to move between pages. Use the left navigation pane or the quick links on this page to go directly to a particular chapter or subject.
-Mike Syphers


About This Web Site About the Author
The Oughtred Society United Kingdom Slide Rule Circle International Slide Rule Museum
18 May 2026