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technology of the past slide rule

Slide Rule Manual

Submitter: Think your posts on computer viruses are something? How about books about calculators that were obsolete when Bananarama was on the charts, or a book on using a freaking slide rule that’s positively Paleolithic.


Handheld Calculator: Use and Applications

Holly: Amen Submitter! These belong in a museum!  They are absolutely useless in a public library.  We’ve had a few examples of old time calculator/computer technology in past posts.  This time, I want you all to go to your 500’s (yes, these are cataloged with the sciences…) and weed your hearts out.

Mary:  This reminds me of my high school math teacher who brought one of those super cool calculators to school to show us.  Cost was around $100 back in the 70’s.  Now I can get them free from my bank.


  1. How can that HP book be from 1997 when it’s about a conference held in 1999? Besides that, I think the calculator pictured on the front is much older. My husband had one very similar to that when we got married in 1983.

  2. Actually the HP one is still quite relevant. In some trades, especially accounting and the like, the HP handheld is still a useful tool. If you go to any good office supply store, HP financial calculators that look like they date to the Reagan administration are still on sale. And when you consider most HP calculators use Reverse Polish Notation, a book on how to use them is quite helpful. The others books, well, not so much.

  3. Regarding the first book, “Guide to HP Handheld Calculators and Computers,” apparently Dr. Mier-Jedrzejowicz is an expert on HP calculators and the book is an illustrated history of HP calculators, now in its 5th edition. From a PDF found on HP’s own website:

    One of the most popular of Wlodek’s books about HP calculators, especially with collectors, is A Guide to HP Handheld Calculators and Computers. This book describes each model, its history, its basic features, and the family it belongs to, usually with a colored photograph. A comparative dollar value is provided along with information regarding its rarity – which is also useful for sellers.

    Based on that, I wouldn’t be so quick to toss that book into the weed pile, especially at an urban public library.

  4. Flashback to my high school math classes! I think I had that calculator (on the third book) or one that looked very much like it. My calculus teacher had a graphing calculator and that was a really big deal. Now the students in the upper math classes can check one out with their textbook, and the rest of the kids can check out scientific ones. Back in my day we had to buy our own …

  5. If that information is available online, then dump them. Space is tight and all books we own cost us both money and space. I am afraid of what we have in storage. I know were paying for them and there taking up space. Yikes.

  6. My uncle is somewhat famous in computer science circles, having designed quite a few of the early ones and collaborated with various folks on problems like how to teach computers to interpret mammograms. And he still uses a slide rule. I have my dad’s old slide rule, and wish I remembered more about how to use it. So move that one to the reference section!

  7. I’d love to see the instruction manual for the calculator on the cover of the last image. You’re really going to get alot done with a four button calculator!

  8. Still remember my attempts to use a slide rule in high school in the early/mid 1970s. I remember when the student from the wealthiest family in town brought a calculator to school. All of us–including the teachers–were amazed at how fast it worked. For several years there was a ban on calculators–all work had to be done on slide rule. If you showed me a slide rule today, I’d have no idea how to use it.

  9. The information in the HP book is probably still applicable. Plenty of banks issue HP Financial calculators to their new hires on the first day.

  10. See, when I was in high school, it was a big deal when we upgraded from TI-83 Plus graphing calculators to TI-84 Plus, in special “school bus yellow” (to prevent stealing, I believe). It’s hard to imagine people ever getting excited about simple ones. They don’t really do anything you can’t do in your head, other than scientific calculators doing logarithms and square roots, but you have to enter things in such a convoluted way, I’d almost rather use a table.

  11. Ahaha, reminds me of my school days. When we reached that grade (I don’t remember which one) when we started using this kind of big calculators, I had a hard time just buying one – they were rather expensive and my family wouldn’t send me any money. I borrowed one of my friend’s for weeks before he eventually lend me the cash I needed to buy mine. I lost it a couple of days before the final exam, and was so desperate that the teacher lent me her own calculator. It was a different model and I had no idea how it worked.

    Ewww, I was about to say ‘thanks for the memories’, but in fact, I hate these calculators 😀

  12. The HP calculator is a great tool; I use it daily and even have an app for it on my desktop computer when the actual calculator is not handy. I would keep that book. Don’t be so hasty to demean something you may not use or be familiar with.

  13. Now, y’see, I too have my dad’s slide rule from his days as a budding engineer. He later became one of HP’s top Systems Engineers. I’d love to have that slide rule manual.

  14. The calculator on the HP Handheld book looks exactly like the one my mother used in college, and then I borrowed it for my freshman year of high school almost 15 years ago. It ran on a 9 volt battery and was an inch thick and you knew that it was time to change the battery when the calculations started coming out all weird. I later bought a TI-85.

  15. Lurker–Okay, fair enough. But most of the people using simple calculators never need square roots. It’s mostly either elementary school kids or people balancing their checkbooks.

    One of my math teachers in high school could do square roots in her head, though. It was rather impressive, though I imagine it was mostly just due to experience. She did it for a problem once, and everyone was so impressed she had us give her a few more just because. She would usually get it within .01, and in a really short time.

    I had forgotten about that, actually.