Cabinet of Curiosities - Day 15

Today we have two related curios.

The fuirst item is my Slide Rule and case.

I am sufficiently old enough to have been issued with this while at school for use in maths lessons.

The slide rule was an analogue calculator. If you knew how to use it you could do multiplication and division, and more complicated functions involving roots, logarithms, and trigonometry. I always found it incredibly tricky to use (I'm not good with numbers at the best of times) and a slide rule isn't much good for addition or subtraction - the two things that I needed most help with on a daily basis.

I was therefore delighted when the first pocket calculators appeared in the shops ... but they weren't quite what we're used to these days.

Which brings me to today's second item, my Magic Brain Calculator.

I bought this extraordinary things in 1974 with money I earned as a paper boy. 

It's a mechanical calculator and it really works.

The first recognisable electronic pocket calculators started to appear in the mid-1970s but they were very expensive - usually in the region of £75. That's the equivalent of around £750 today. The first low-cost calculator was the Sinclair Cambridge, launched in August 1973 but even that retailed at £29.95 (equal to £428 today). 

They did get cheaper fairly quickly though and, by 1980, everyone could afford one and I could consign my slide rule and Magic Brain calculator to a deep dark drawer, never to be seen again except for guest appearances in future blogposts.

You youngsters don't know you're born.