Sterling DeciTrig plus shadowbox

Slide Rules!

Last Updated: 7/9/15
Demonstration rule added to gallery.

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: 7/9/15 with Picket N902-ES demonstration rule


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 2/4/04 with a few notes at the bottom.


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.

Slide Rule Trading Company

    While this site sells "new" and used rules, they specialize in replacement parts and general repair stuff, plus accessories (cases, paperwork, etc) to help you take that loose rule off eBay and kit it out with all the extras. Hemmi and Post brand rules have the deepest selection. Updated 3/1/10 (but as of 2017 it seems to be dead).

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. (Page appears to be dead.)


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.

The Slide Rule Guy

   This came to my attention via a link on Make Magazine for the World's Biggest Slide Rule. (Page seems to be dead, or badly coded.) :)

Java Slide Rule Page

    The old page I had up with a Java slide rule is definitely dead. A reader supplied me with this new link. (Which is now also dead.)

Derek's Virtual Slide Rule Gallery

    Take the geekitude of the previous link and augment it. Numerous simulated slide rules!

Concise Sales Page

    Concise is still in operation, in Japan at least, and this page describes how to order from them. (Link seems to be dead)

ThinkGeek Slide Rule

    ThinkGeek is offering a new slide rule that's a replica of the Pickett M-120 (as fat as I can tell), selling it for $29.99. Of course, actual M-120's are pretty easy to find for less, but if you don't like the idea of using someone else's leftovers, you can get one here new. (Or not, redirects to a general page now with no slide rules.)

Hemmi Catalogue Raisonne

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


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