Sterling DeciTrig plus shadowbox

Slide Rules!

Last Updated: 1/16/21
Pickett Model 3 added to gallery, some of its new indices added to primer.

DISCLAIMER: I do not sell slide rules or slide rule parts.

    This page is dedicated to my collection of slide rules (moderate in size, fairly low in value), plus a few helpful links for those who want to find out more about the playful little things, or where to buy one. The picture to the right is me with some of my slide rules, as taken by Columbus Dispatch photographer Neal C. Lauron. The Dispatch did a piece on "Dinosaur Technology" in the business section on July 5, 1999, and I was interviewed as a local source on slide rules. And yes, I did shave two hours before the photo was taken...something about the digital camera apparently picked up on an otherwise undetectable two hours' growth of beard.

    Few things in history have become so completely and quickly obsolete as the slide rule, replaced by the electronic calculator and portable computer. Even abacuses are still used in some circles, but everyone who would have used a slide rule now uses an electronic calculator instead. Well, everyone but collectors and diehards. :) Thing is, slide rules aren't inferior to electronic calculators in all respects, and there's certain things a slide rule might even help students with, such as estimation and order of magnitude. Unfortunately, because the demise of the slide rule was so rapid (less than ten years, really), and because no one thought to do comparative research at the time (not that I've been able to find), it's impossible to really say if slipsticks are better at helping knowledge stick. Of course, if you can point me to a scholarly study, I'd be grateful (physics education research is my area of study in "real life").


Slide Rule Gallery

    My personal collection, which continues to grow very slowly. Someday I'll get around to taking fresh pictures of all of them, but for now most are the result of sticking rules on a scanner in the 1990s.

    Last updated: 1/16/21 with Pickett Model 3 in Long Rules.


A Slide Rule Primer

    While the HP Museum below gives some basics on slide rule operation and has links to other pages with such information, my page seems to show up pretty high in search engine results, so I get the occasional "how do they work?" questions. This straight-text file gives a short lesson on how to use the more common slide rule functions. It does not, however, explain the math involved...if you don't know what a logarithm is, or what it means to take something to the 3/2 power, consult a mathematics text. :)

    Updated 1/16/21 with CF/M and Co scales. Should probably go back and tighten the file up at some point....


Slide Rule Links

Disclaimer: link rot sets in pretty fast for some of these, if you know of replaecment links for any now-dead ones, or have suggestions, please let me know.

Giovanni Breda's

    Domain name notwithstanding, this page is in English. Giovanni Breda has a truly extensive collection.

Oughtred Society Slide Rule Seminar

    A set of slides in PDF form prepared by the Oughtred Society, covering the history of slide rules and some basics of their use.

Museum of HP Calculators Slide Rule Page

    A VERY cool page with all sorts of explanations of how sliderules work and pictures of various types, including circular and cylindrical. Recently moved to a new site and upgraded. No frames, just nice use of tables. I've changed the link to point directly at the section on slide rules and their history, click here to visit the main HP Museum page.

International Slide Rule Museum

    Another museum site, this devoted specifically to slide rules rather than calculating machines in general. It also has a really nice glossary of terms, including scales, parts, and company names all in one place.


Dave Crate's Quality Slide Rules

    Another slide rule sales/trade site, carrying both like-new rules and more "lived-in" rules. Has a LOT of images, a good resource even if you're just looking around. I don't really trade in rules myself, so I can't give any estimates of the value of your rule, but Crate should have some idea.

R.E. Manley's Slide Rule Page

    Among other resources on this page is a nearly complete "Teach Yourself The Slide Rule" manual that Manley has scanned in. Useful if you find my primer to be somewhat lacking.

Derek's Virtual Slide Rule Gallery

    A whole bunch of simulated slide rules! As of July 18, 2017, it includes: Pickett N909-ES, Pickett N3-T, Pickett N904-T, Pickett N525-ES, Pickett N4-ES, Pickett 160-ES Microline, Pickett N600-ES.

Concise Co. Ltd. Page

    Concise is still in operation, in Japan at least, and they have products like the 300B circular rule for sale. (Moved to a new domain since last time I updated the links.)

Hemmi Catalogue Raisonne

    This presents itself as the "complete authoritative listing of all Hemmi slide rules ever made."


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