Slide rule history of maths before technology

When i left school and started work it was in the days before calculators, although i had done computers in school and programming in Cecil (simple programming language developed to teach in uk schools) and then BASIC on punched cards marked with magnetic pencil the industry i worked in had not discovered modern technology…

Along with my lab coat i was given a slide rule and a lesson on how to use it. This object became my best friend and most of the day it went around with me even to university where i was one of the few who were quicker at calculations using it than fellow students.

Forgotten technology but worth remembering?

I was surprised when my step son had never seen one and had no idea how it worked, having just finished his masters in computer science.

Yes i still have mine but no longer need to carry it.

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I owned one too, but was never very good at using it.

But punched cards. Yes, for many years. Not unusual to have 2 or 3 rubber bands on my wrist to wrap around cards or in case a rubber band broke that held a deck of cards together.

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My nephew is an accountant. He had never seen a side rule. I had to explain that it was based on logarithms. He understood logarithms, but not a slide rule?

A slide rule was comupulsory equipment at my first year University. In second year I encountered mechanical calculators in a statistics course. Never saw a computer until I became a postgrad.

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OK Paul. That was REALLY awful. I remember all those things you mentioned, which in turn, reminded me of just how ancient I am. I remember when the Dead Sea was young and vibrant.
Seriously though, those were the best of times. It was all uncharted lands filled with original ideas and yes, I still have my old wooden and brass slide rule.

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I agree. Science 50-60 years ago was in an age of discovery.
It was exciting . Young people really embraced careers in maths, science, and engineering.
I dont really know what Universities are like today or where all the enthusiasm is located.

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Like you all feeling my age.

Find it hard to get excited by new technology where they are not really inventing or finding new things. What is the difference between m1, m2 and now m3 chips except speed. Same with intel and amd should i buy a … core or … core.

My last university teaching job is now almost 40 years ago and i gave it up to move into working with the technology to learn more. My step sons uni work is mainly calculations on signal strength and distance for his masters nothing new or exciting or cutting edge, which i feel is a shame. But thats a french uni, perhaps not all the same.

I had a student come to work for me having just got his masters and his thesis was on the lift in the university building on numbers of users, direction, time spent … boring and not of use except in statistical analysis, he did not last long in my world of client faced technologies or problem solving.

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OK lets have a vote…
What is the most exciting, ground breaking scientific work
in recent ( ie about last 40 years) times

My vote: Chaos theory and fractals

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Found mine in a garage box being purged. It was snuggled next to a circular slide rule that was my constant companion in college. May hang them on the wall.

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Never seen a circular slide rule, did it work the same ?

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New topic ?
Best over the last 40 years ?
For me communication mobile, internet and the related, but do they class as scientific

For science stuff

If it works the injection for cancer which is being tested right now, imagine if it solves cancer totally… but on the same area radiotherapy which has advanced in leaps and bounds… but xrays are still black and white.

I am mainly researching that at the mo as it touches me personally

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Yes, but very fiddly to use in my opinion.
It has log scales around the circumference of circles… it is not a circular scale like a compass, it is still linear.

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1.3 on the D scale times 2 on the C scale equals 2.6 on the D scale. At least that’s how I remember it working.

Really kind of fiddly, but I remember it being pretty useful in physics in 1965-66. Most of the problems were set up for slide rule computation, which made its linear format (correct, Nev) handy.

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Thanks for sharing tye photo
Quite rare object never seen in use

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When I was an EE undergrad we all had slide rules. The majority had wood (bamboo?) models, K&E brand. I think bamboo has a low thermal coefficient of expansion. You were slightly more nerdy if you had a Dietzgen bamboo model. If really nerdy, a straight yellow (metal) Pickett (had more scales), and maximum nerdy, the circular Pickett. They were all sold at the U. Bookstore. We had to know how to use ALL of the scales. I would need a refresher course on all but A & B today, but I still have my Dietzgen. 4.22E6 / 2.11E9 = 2.00E-3

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Never seen a model in anything other than white plastic. Did not know they existed or were used outside of the uk. Time before internet and doing research. I too was originally a metallurgist, for some unknown reason in France metallurgist and computer science are considered the same discipline and the most important uni is based around the two.

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Yes, bamboo slide, but coated with plastic containing the scales. About 3 digit precision on simple calculations.
I could do better with log tables.

Early computers had no multiply hardware. They multiplied by successive addition. They did not use logs for multiply.

I worked on one computer that worked with decimal coded numbers, and it kept a set of multiplication tables in its memory and used table lookup to multiply… the same way humans do

Hollerith card machines could add, so they could be made to
multiply if you programmed them ( with plugwires) to do successive addition.

Mechanical calculators could multiply. Not sure but I think they used successive addition. Some could even do square roots.

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Forgot all about log tables…
Not sure i could even use one now without help and guidance.
Sine cosine and tangent were in the same book but again forgotten ideas
Along with long addition for multiplication
We take it all for granted now with tools like excel and its built in functions

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I had this book when I went to college. It was a graduation present.

image

Mine was a revision or two older than that I think.

For a party trick I memorized Pi to 51 digits. I can still recite that. :slight_smile:

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At least since computers are binary, they do not do successive addition for multiplication, but make clever use of the shift operation (which can also be done mechanically):

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I have collected several slide rules including my log-log slide rule from college (50+ years ago). I tried to use one recently, just to see if I could still do it. I found that it’s very very easy to make a mistake and I gave up. There’s one on my wristwatch that’s good for the time/speed/distance calculations that pilots need to do. As a groundling it’s just decoration for me.

Slide rules go back pretty far in history. The early ones had no cursor. That improvement was invented by no less than Sir Isaac Newton.

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