Slide Rules!

Last Updated: 8/29/07
Link added.


   DISCLAIMER: I do not sell slide rules or slide rule parts. Nor am I currently looking to buy, as I'm paying off a new car and am trying to cut back on expenses a little.

    This page is dedicated to my small (but growing) collection of slide rules, 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 hour's 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

    This page was starting to load pretty slowly, so I decided to move the gallery of my growing collection off to another page. Last updated: 1/25/07 with an Altitude Correction Computer and more info on some previously posted 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 2/4/04 with a few notes at the bottom.

Slide Rule Links

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.

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.

The Slide Rule Guy

   This came to my attention via a link on Make Magazine for the World's Biggest Slide Rule. :)

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.

Derek's Virtual Slide Rule Gallery

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

Send e-mail to dvandom@eyrie.org.
BACK TO: Main Page Physics Education