Where Have all the Slide Rules Gone and Should Engineers Care? #Calculators #History

Design News has a slide deck discussing slide rules, mechanical calculating devices used prior to electronic calculators being ubiquitous.

The above picture shows a 1930s high school class making electrical calculations on their slide rules. Note the demonstration-sized rule hanging on the blackboard, taken from Keuffel & Esser Co., Drawing Instruments and Materials for High Schools, Preparatory Schools, and Manual Training Schools.

The slide rule sometimes called a slipstick in the U.S., is a mechanical analog computer. As graphical analog calculators, slide rules are closely related to nomograms, but the former is used for general calculations, whereas the latter is used for application-specific computations.

See the video below and the slides and their explanations here.

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  1. I was thinking about slide rules. They don’t require batteries and won’t break like a calculator might. They operate when the power goes out. There is probably more theory and wisdom contained in slide rules because someone with just a calculator doesn’t always know how to operate on a math problem. Slide rules come with the algorithm and pre-programmed..I’m missing a lot of wisdom and an era. There is probably more visual teaching in a slide rule than just letting a calculator handle the problem.

  2. Faber-Castell – International Slide Rule Museum

    https://www.sliderulemuseum.com › Faber

    A.W Faber, later Faber-Castell, was a German manufacturer of slide rules, starting in 1892, that began as A.W. Faber pencil factory as early as 1761. They are celebrating their 250th anniversary as of 2011. Slide rules started out as boxwood, with celluloid facings added in 1897.


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