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Calculation before we went digital [pdf]

nicolamarras.it

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Re: Calculation before we went digital [pdf]

#3
Clearly not written by someone with native English ("subtract is became easy" is particularly memorable), but still not hard to understand, and the content is very interesting although it jumps around a bit --- I like how "physical" these early calculating machines are, as one could easily see the process being carried out.

Re: Calculation before we went digital [pdf]

#5

Clearly not written by someone with native English ("subtract is became easy" is particularly memorable), but still not hard to understand, and the content is very interesting although it jumps around a bit --- I like how "physical" these early calculating machines are, as one could easily see the process being carried out.

Indeed, for learning arithmetic and many other areas of mathematics, being able to do calculations physically is better than (optimistically speaking) 90% of what goes as "ed tech" these days. Cuisenaire rods teach you basic counting and get things like 3+7=10 into your subconscious (or, if you have synaesthesia, also green+black=orange). The abacus, back when it was taught, made place-value and things like "to subtract 8 you subtract 10 then add 2" a physical as well as a mental operation which helps with math learning the way phonics helps with reading. Later on, of course, slide rules do the same for logarithms (as is explained in the linked PDF).

I wish we had more of this back in our classrooms.

Re: Calculation before we went digital [pdf]

#6
I still have the Odhner calculator, as seen on page 19 of that PDF, that my grandfather was still using at his SME in the eighties (he owned a little SME making tailor-made clothes)! I think that at some point in the fifties he bought a stock of desks, calculators, typewriters, etc., used, from another company. And then he kept using these old machines for decades.

As a teenager I'd go help for a few bucks: I'd use the typewriter to write letters plus actual "carbon copies" (literally putting two or three sheets of paper separated by a carbon sheet).

Never understood how that Odhner calculator worked but I still have it (and I had no idea it was from 1920: TIL)!

P.S: I also wrote my first program used "for real" back then: I wrote a program on my Commodore 64 that'd compute the discount for his clients (like, say, hotels) according to how many suits they'd buy. And I printed the results on a dot-matrix printer. This saved my grandpa lots of time!

Re: Calculation before we went digital [pdf]

#7
For those who wish to learn more about the slide rule, I recommend Asimov's (yes, that Asimov) book, "An Easy Introduction to the Slide Rule." I was lucky to pick up a physical copy as a young man, but it appears it's available as a PDF online.

That, plus any of the $10 vintage slide rules on eBay, opens a while new world of fun. I still use slide rules fairly regularly. I find that I gain better understanding of the equations I use the most when I can reformulate them for easy solving on a slide rule (e.g., so you can solve an equation with two operations with one slide move).

Re: Calculation before we went digital [pdf]

#9

I still have the Odhner calculator, as seen on page 19 of that PDF, that my grandfather was still using at his SME in the eighties (he owned a little SME making tailor-made clothes)! I think that at some point in the fifties he bought a stock of desks, calculators, typewriters, etc., used, from another company. And then he kept using these old machines for decades. As a teenager I'd go help for a few bucks: I'd use t…

>literally putting two or three sheets of paper separated by a carbon sheet

I had to chuckle at your use of "literally", as I too (and probably many others here) would never imagine that there was a figurative way to do this. I should add, carbon paper is not literally made out of carbon.

Separately, I noticed the image of the Playboy Magazine cover used in the article. It was customary for them to always include the bunny logo somewhere as part of the image; in this case it is embossed on the leather case for the slide rule.

Re: Calculation before we went digital [pdf]

#10
People with interest in calculators might be interested to read Empire of the Sum by Keith Houston, which provides some historical notes on calculating before the electronic and digital revolution.

-- A proud owner of a Faber Castell slide rule, inherited from my father, and an Odhner mechanical calculator, from my grandfather.

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