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Posted by: dvandorn Feb 19 2006, 05:26 PM

Here are two nearly identical images. One of these was used by Sergei Korolyev, the other by Wherner von Braun. Can you tell which is which?

And here's a more interesting question -- how many of us here on UMSF have actually *used* a slide rule in their lives? I know I used a slide rule, even in a completely non-engineering field -- I'd use it to do basic scaling functions when doing layout on newspapers and such.

Since both Neil Armstrong and Buzz Aldrin took their own personal slide rules to the Moon, people were obviously using them only 35 or so years ago. So, how many of us have ever used one?

-the other Doug

Posted by: helvick Feb 19 2006, 05:56 PM

I owned and used one but never in an actual work context. By the time I got to high school level calculators had become quite common (1979) and slide rules were definitely well dead by the time I hit college in 1983.

My education seems a bit archaic now when I compare it to my kids. Lots of mental arithmetic, rote learning and the like compared to the emphasis on research, analysis and presentation that I see my kids having to deal with.

Posted by: tty Feb 19 2006, 06:09 PM

I was born in 1948 and I certainly used a slide rule back in the 60's in high school.

As I remember it I first used electronic desk calculators and minicomputers (HP1000) as an undergraduate in about 1970 or 1971, and bought my first pocket calculator (also HP, RPN (anybody remember that?)) at about the same time. It was quite expensive.

The first PC I used on my job was a Commodore PET in about 1978, and my first private PC, a Microbee Z-80 CP/M machine with 32K memory and a cassette tape recorder as "mass memory" in about 1982.

Time flies!

tty

Posted by: CosmicRocker Feb 19 2006, 08:42 PM

My experience pretty much mirrors tty's. I still have my Post Versalog 1460. I used it in high school and for a couple of years in college, but the chemistry department eventually purchased a cabinet-sized calculator (can't recall the brand), and we all went wild for it's ability to display our results to a level of precision that far exceeded that of the input data.

When the handheld calculators came out I eventually bought an HP with RPN. I only use HPs with RPN and wouldn't have it any other way. I am such a fan of RPN that I insisted that my children use HPs with RPN as they grew up. They learned to appreciate it's calculation efficiency and the side benefits. Few if any of their friends ever asked to borrow their calculators, people were less likely to steal them, and if some one did steal one, you at least had the satisfaction of knowing they would probably not know how to use it.

As for your first question Doug, I can't tell which is which.

Posted by: Bob Shaw Feb 19 2006, 10:00 PM

I can't tell the slipsticks apart, either!

In the world of fiction, a high proportion of Robert A Heinlein's classic characters would have sooner walked naked across the surface of Luna than be without their trusty slide rules - and who can forget the Kelly Freas Analog cover for Gordon R Dickson's 'Hilifter', featuring a mangy space pirate boarding a fat treasure vessel, trusty slide rule between his teeth...

I *have* regularly used a slide rule (although specialised in form), and even in fairly recent times, and *yes*, they're still very much in use in an area which ought not to be a surprise. I'd wager that *most* astronauts are very familiar with that particular device. I'd be entirely unsurprised to hear that a few of the specialised variety have made it into space, too... ...and perhaps not just for fun!

Let's see who's first to have that smack on the forehead moment - and then I'll post a scan.

Bob Shaw

Posted by: jamescanvin Feb 19 2006, 10:07 PM

Surprisingly (being only 28), I have used one. One was found one in my office a few years back*, googled for instructions and then wasted a few days of my PhD trying to get the hang of it. A really fasinating bit of kit, really worth getting your hands on one if your from the 'pocket calculator age' like me.

*Stuff NEVER gets thrown out of academic offices, all sorts of historical stuff turns up. Only last week my office mate came across the manual for our departments first computer. Informing you how to start the machine - by manually coding the startup program by toggling switches!

James

Posted by: helvick Feb 19 2006, 10:17 PM

My gut feeling on this is that it's something to do with flying and navigation. It would seem fairly sensible to demand that if all else fails that pilots would have an extremely solid state reliable calculator on hand.

Posted by: Bob Shaw Feb 19 2006, 11:34 PM

That's the one. Pilots use a so-called 'computer' - a circular slide rule - to calculate a wide range of values associated with flying. Anyone who trains in the UK to fly as a private pilot will have been exposed to such a device (or should have been, anyway!). And I'll be astonished if none have made it into orbit!

Bob Shaw

Posted by: dvandorn Feb 19 2006, 11:43 PM

FYI -- the top one was Korolyev's, the bottom one was von Braun's. The real point is that you can't easily tell the difference by looking at them -- the science and engineering was the same, followed the same rules, on both sides of the fence.

-the other Doug

Posted by: BruceMoomaw Feb 20 2006, 01:09 AM

While we're on the subject of lack of Cybernetic Foresight among otherwise visionary SF writers, we musn't forget Arthur C. Clarke's "The Sands of Mars" -- in which a reporter onboard one of a regularly scheduled line of Mars-bound ships runs into trouble with his dispatches because the ship's fax machine can't read the carbons from his typewriter properly...

Posted by: Bill Harris Feb 20 2006, 02:59 AM

HP with RPN and sliderules, what a nostalgia trip!

I used slipsticks ("linear" and circular) in college 35-ish years ago, and as late as 20 years ago kept in practice with using the sliderule. Heck, my intro computer course spoke Fortran with data input on Hollerith cards.

And all that was state-of-the-art.

--Bill

Posted by: elakdawalla Feb 20 2006, 03:20 AM

What's a slide rule? Just kidding, but in all seriousness while I have seen photos of them I have never actually held one used for engineering/navigation in my hands (I had to add that qualifier because my father collects and uses antique carpenters' tools and has a couple that were once used for figuring scales and angles and such), much less learn how to use it. I did, of course, do lots of timed tests of arithmetic in my childhood; but several years ago I was teaching fifth grade science at a reasonably good school and was astonished and disgusted to discover that none of the kids could multiply or divide by ten without a calculator. (For you non-Americans, fifth grade students here are 10 or 11 years old.) Sigh.

--Emily

Posted by: BruceMoomaw Feb 20 2006, 03:48 AM

SF writers prove prophetic again! Remember Asimov's "The Feeling of Power"?

Seriously, this just proves that American education is even more of a scandal than we thought. I already knew that American students weren't being taught silly little things like grammar (MUCH easier to teach them "self-esteem") -- but how can you even use calculators to solve a real-life math problem unless you understand the logical principles underlying mathematical operations, so that you know when and how to apply them? And they can't multiply or divide by TEN without a calculator? Jesus.

Posted by: edstrick Feb 20 2006, 06:25 AM

I've still got my slide rule. Though once the calculator age, I usually used it mostly as a log ruler for making quick and dirty graphs without log graph paper.

I've also got at least one of the BAMBOO slide rules my brothers had in high school. Dense, solid, oddly slippery, and very stable mechanically. A most interesting material.

A neat curiosity I have is my first Calculator. A Melcor 1000 (I think.. have to dig deep in a drawer to find it)... the first $99 full-function scientific calculator from 1975, advertized in Scientific American (mail order only)

It's probably the only calculator that was ever advertized and sold as having a defective main chip!

It literally comes with an errata-slip that explains that the Cosine of zero is not zero but is actually one.

Apparently, somebody, I presume TI, since it's not a reverse-polish-notation calculator, made up a whole batch of very very very slightly defective calculator chips and somebody else was willing to use them in a commerical product!

Posted by: tasp Feb 20 2006, 02:56 PM

Well, I recall using a slide rule a few times.

In High School, probably my Junior year, I purchased a Commodore SR-1400 (IIRC).

It broke and it was repaired (!) under warranty. I took the back off and they had replaced a couple of chips in it. Can you imagine trying to repair a calculator these days?

I also recall using a key punch around 1975.

Those computer cards seem as primitive as counting with sticks now days.

I have a 25 year old (~) HP-41CX that still works and sees use. I do not have anywhere near the skills with it as I used to.

Posted by: tty Feb 20 2006, 08:14 PM

I never actually used a key punch, but the first mainframe I worked with (an IBM 7074) used Hollerith cards, and I've written untold thousands of 80-character lines for punching by some other poor devil.

I fully agree with Bruce, I can't understand how anyone can use a calculator without enough mental arithmetic to at least understand what he is doing, and noticing if the result is completely wrong, but maybe the younger generation never punches the wrong key...

tty

Posted by: mchan Feb 20 2006, 08:31 PM

I have used slide rules and card punches briefly. Don't miss them at all.

I still use my HP RPN calculator. Some of these fetch very high prices on Ebay. E.g., an HP-42S in mint condition goes for over $300. The original retail price was $120. HP still makes RPN calculators, but they don't have the solid feel of some of the older models.

Posted by: Bob Shaw Feb 20 2006, 10:26 PM

It's not just US education that has a problem with numeracy - so too does the UK. I think, though, that there were always many people who were barely numerate, but that they were forced to learn simple skills by both school and their environment. These days calculators are ubiquitous, and when they are not to hand even educated folk crumble...

In the UK we suffer from Value Added Tax at 17.5%, which I generally work out in my head if I need to get a general idea of a real price (many of the goods I purchase are priced ex-VAT). I shudder whenever somebody reaches for a caculator, especially when I've got the cash already in my hand. As for making change...

I may have to move to Yorkshire at this rate. Luxury, that's what it'd be, bloody luxury...

Bob Shaw