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Oughtred Society Archive of Slide Rule Collections

by richardjam73 on 10/16/23, 11:45 AM with 22 comments

• by coldpie on 10/16/23, 2:47 PM

  I inherited two or three slide rules from my father. One of them is circular shaped. Once or twice he showed me how to do some basic calculations, and I've spent ten minutes here and there with various online tutorials, but I've never put the time in to actually understand it, so I always instantly forget how they work. Kind of a shame, but I hang on to them anyway. They're cool artifacts from the pre-computer world.

  Hm, I wonder if it could be a handy way to do fractional computation while I'm doing woodworking? If so, that could be a good excuse to finally learn how to use one.

  (Strangely, my work's proxy blocks this domain as "pornography." Interpret that as you will.)

• by denton-scratch on 10/16/23, 2:54 PM

  At school I was introduced to several calculation aids:

  * Slide rule

  * Mechanical adder

  * IBM Schools Computer

  The IBM wasn't actually much of an aid; it had no persistent storage, and you had to program it in hex, from the console.

  The mechanical adder was marvelous; you toggled in the arguments using metal wheels, and then cranked a handle on the side to do additions. We actually used them to do sums; there was a cupboard in the maths classroom, with enough machines to have one on each desk.

  My father left me a Faber slide rule from the twenties. Wood, with ivory lamination, and a nice, delicately-sprung cursor. We never used slide rules at school to do computations, we only used them to learn how to use slide rules (which was therefore a complete waste of time).

• by mschaef on 10/16/23, 1:13 PM

  It's really worth looking at a few of the collections. There are lots of slide rules on display, and many if not most are far beyond plain linear slide rules. (Most are special purpose and application specific.)

• by ararar on 10/16/23, 7:58 PM

  Concise Co. of Japan still makes slide rulers albeit only circular ones (https://www.sliderule.tokyo/products/list.php).

  One prominent industry that still uses slide rulers is aviation. They use "flight computers".

• by OldGuyInTheClub on 10/17/23, 5:22 AM

  I've been meaning to dust off my old slide rule for a long time. Learning to use one circa 8th grade made future science so much easier. Had to think of significant figures ahead of time, spend a few moments to plan the computation, and get comfortable with when to approximate and how. Pretty soon I was able to get a sense for what answers ought to be, at least to within a factor of 2-5. Anything outside of that and I knew I'd made a mistake somewhere.

  I also loved the old HP calculators of the late 1970s to late 1980s and eventually set the slipstick aside but am ever grateful for what it did for me. And for fellow RPNthusiasts, there is the Museum of HP Calculators at https://hpmuseum.org/

• by ftio on 10/16/23, 2:11 PM

  I knew exactly what this website would look like just by reading the title. Absolutely perfect. Form elevated to content.

• by sleepybrett on 10/16/23, 4:58 PM

  I feel like being gen x i might have been part of the first wave of kids never to learn to use a slide rule. I'm actually not even totally clear on what they are even for.

  I am really digging some of the other mechanical calculators in the collections though. Always love to see a curta.

• by dudeinjapan on 10/16/23, 1:46 PM

  Just like some people prefer vinyl over digital audio, I've always felt my division is warmer when using a slide rule.