Monday, 16 November 2009

Slide rules OK...

Lils has prompted - nay; cajoled - nay; jugularised me to do this post which I once threatened I'd do for Elbers who is a clever chap (much cleverer than me), and only because I'm possibly a dormant nerd passim, a hoarder, a collector, a greying, shambling, emotional won't-let-the-past-go-type-of-bloke-with-stuff-in-the-roof-which-he-just-can't-chuck-out; - er - yet...

So here it is!

A post on Slide Rules!

There; I've said it, and I must tell you what a relief it is to mention how much I'm going to enjoy life from now on!

My Dad used a slide rule all his life. It was an engineer's calculator, a scientific object to fiddle with on your desk, a magical instrument to teach your son when you're taking him away to Wales to boarding school, and need to occupy the lad until he's either bored to tears, or just full of tears.

Dad had at least three linear slide rules, and another cylindrical model here

which for the life of me I cannot understand one bit!

For intricate calculations, he'd use a single bar linear rule which was about two feet long, and was incredibly accurate. He then graduated to stellar numerology...

This pictured Otis King model 'L' was the bees knees up until the late sixties, when electronic calculators came on the scene. I worked in Westminster in a Quantity Surveyor's office then, and we had calculators which cost £350.00, and were the size of a multi-tasking printer from Currys now! They were huge, and did peculiar things if you pressed all the keys at once, then left it to smoulder; which we regularly did after taking bets on the number which would flash up after lunch...

But these slide rules are a bit special still, and they don't need batteries, and they still work after fifty years, and - well, they're a bit of Scrobs' history...

22 comments:

Calfy said...

OH! I want a cylindrical slide rule! A real one! Really badly.

Thud said...

I too want one...musst have one now!

Blue Eyes said...

My dad always promised he would show us how to use his... he never did :-(

I must have been one of the first generation of school calculator-users, Casio having kicked Sinclair's arse in the late 70s/early 80s?

Philipa said...
This comment has been removed by the author.
Philipa said...

I used a linear slide rule at school and I too used a calucluator when they were brought in but twas early 70's for me. By the time I went to Uni they were thankfully much smaller and did more stuff. It was still a Casio. I still have it, and my log tables somewhere. But sadly I don't have a slide rule. I'd love to have a go with the cylinder one :-)

Scrobs... said...

There seems to be an unhealthy interest in the cylindrical slide rule.

Yes, it does extend (from 6"to10") with the flick of the wrist, and yes, it needs to be gently massaged around the cursor, and some careful eyesight, is required to make sure that everything arrives at the right place at the right time...

I reckon the linear one is better - much longer, slides easier, and can easily be slipped into the pocket when not in use!

Scrobs... said...

Calfy, Thud and Pips - it's not for sale...

Oh all right, you can borrow it but I WANT IT BACK!

I lent one of the Faber super-bastard ones to a chum at school, and he didn't give it back after his exams.

He's a Doctor (retired) now, and Pete, if you're reading this, I told one of your patients the story, and he didn't get an answer either!

WHERE'S MY BLOODY FABER CASTELL SLIDE RULE???

Scrobs... said...

Blues - I still use a Boots 224 Memory calculator which Dad gave me for Christmas in 1975 (I think).

I saw one in Sainsbury's for 89p last week! Mine cost £5!

It still does everything I want and you can still see several grizzled old farts like me using them...

Elby The Beserk said...

Want. Wish I knew what I did with my linear slide rule.

Calculators. Whenever I used them, I'd check the answer the old-fashioned way; decided they were no use to me!

Philipa said...

Elby - we used to call that checking the order of magnitude (ie. doing it the old fashioned way) I used to write my data down longhand when I was using any FEA package, it really did save time.

killemallletgodsortemout said...

I think you can buy those cylindrical ones - I think they're called Rampant Rules - in Anne Summers.


Batteries Not Included.

Scrobs... said...

Pips and Elbers, when was in a Quantity Surveypr's firm in the late sixties, there was a rigid regime for introducing sprogs to the work.

Although I started a different way (used to be an Estate Agent Elecs...), the firm would start the sprogs straight from school, and they'd be told to sit in s darkened...

Oh sod it, this is to valuable a comment, I'll blog it separately...

Scrobs... said...

Killers, that's rude, and for God's sake don't tell anyone here...

I've put mine back in the roof, it is a marked slide rule and everyone's after it now!

Thank goodness there's only a few of us seeing all this; we'll have Jack Straw's Stazi along any minute!

electro-kevin said...

I wish I knew how to use one.

mutleythedog said...

OK. Whats it for? I have not the first idea ... why cylindrical and 2 metres long? My goodness. Is it some kind of measuring device?

Scrobs... said...

Elecs, well, on a linear slide rule, you push your middle peice anong the outside edges until they line up.

You then look at either A-B scale, or C-D scale, and check along until you see the answer.

Easy!

Scrobs... said...

Mutters, if you read (and believed) any of the comments here - especially from the girls - and Killers; you'd think I'd started a post on "Elongated Artifacts and their place in Society, with special reference to a certain website which seems to offer the impossible or the improbable".

It is indeed a calculator!

But looks like something else, only shorter...

Philipa said...

Scrobs, can you stop talking about pushing your middle piece along the outer edges until... really I've gone all unnecesarry, it's been such a long time since I've enjoyed a slide rule :-)

Scrobs... said...

Pips, just wait until you can get the cursor to meet both numbers in the middle!

It's ecstatic...!

Weekend Yachtsman said...

When I was at Uni we had those early desktop calculators with the red gas plasma displays and - omg - reverse Polish entry systems.

There were about five of them in a special room, they were locked down to the desk in case anyone stole them, and you had to queue up to use one. Honest.

And when I was at school we had the most wonderful mechanical calculators, made by some Swedish firm or other; you hit various keys and then wound a handle like an old-fashioned bus conductor's ticket machine, and lo and behold - the answer.

God I feel old.

Calfy said...

I want a windy-handled calculator too.

The Lakelander said...

When I did O Level Maths, we all used a slide rule that came in a hard grey plastic case.

The class guitar heroes all drew fretboards on cardboard that they pasted to their slide rule cases, so they could fit in quick (but silent) guitar solos in between classes.

I think mine is still in my parents' attic. I was never any good with a guitar.