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Math Hardware

Know How To Use a Slide Rule? 388

high_rolla writes "How many of you have actually used a slide rule? The slide rule was a simple yet powerful and important tool for engineers and scientists before the days of calculators (let alone PCs). In fact, several people I know still prefer to use them. In the interest of preserving this icon we have created a virtual slide rule for you to play with." Wikipedia lists seven other online simulations.
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Know How To Use a Slide Rule?

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  • by the_humeister ( 922869 ) on Friday September 28, 2007 @12:54PM (#20784215)
    There's a reason we don't use slide rules, abacuses, buggy whips, etc. - we have better tools now. I used to have one when I was a kid back in the '80s, never really figured out what it was for, especially since we had scientific calculators instead.
  • Re:Um No. (Score:3, Insightful)

    by pclminion ( 145572 ) on Friday September 28, 2007 @01:00PM (#20784325)

    Sounds like if the global shit ever hits the fan, you're simply going to DIE, because you have no ability to care for yourself.

    Living in modern civilization is no excuse to be ignorant.

  • by cliveholloway ( 132299 ) on Friday September 28, 2007 @01:05PM (#20784391) Homepage Journal
    "The index line on scale C is always put over the number to be multiplied on scale D"

    What's the point of explaining how it works if you don't explain what each of the terms used is?

    Damn nerds...
  • Re:Of course (Score:5, Insightful)

    by mabhatter654 ( 561290 ) on Friday September 28, 2007 @01:06PM (#20784423)
    but in reality, justifying precision more than 4 significant places is really difficult using proper scientific/engineering methods. For instance 4 decimal places in surveying takes you to an inch range even over a mile of distance with hand tools. Average slide rules can do 2-3 fancy ones can hit that last place.
  • Re:Of course (Score:3, Insightful)

    by kalidasa ( 577403 ) on Friday September 28, 2007 @01:11PM (#20784495) Journal
    For engineering, you're right. For other sciences: well, let's just say that you wouldn't want to have to calculate an Earth-Mars transfer orbit with a slide rule.
  • Mildot Master (Score:5, Insightful)

    by dazedNconfuzed ( 154242 ) on Friday September 28, 2007 @01:31PM (#20784791)
    Slide rules are still in active use by - of all people - snipers. The Mildot Master [mildot.com] is a sliderule for determining distances and ballistics for long-range precision shooting when using a rifle scope fitted with a "mildot reticle".

    Simple, low-tech, durable and cheap - specialized slide rules are still useful for particular applications where computers are expensive & fragile overkill.
  • Re:Um No. (Score:4, Insightful)

    by hey! ( 33014 ) on Friday September 28, 2007 @01:39PM (#20784923) Homepage Journal

    I also don't know how to use a Flintlock rifle, trap/clean/spit roast a hare, catch a fish with my bare hands, hitch a wagon to a horse, or build/make/use a butter churn.

    If you were seriously interested in shooting, you'd find a flintlock pretty interesting; you'd have at least a rough idea of how to operate one, although it might take you a bit of time to use it expertly. You'd at least get some pleasure out of messing around with one, and maybe take some lessons back for shooting modern firearms. If you were seriously interested in cooking, you'd have a pretty good idea of how to clean, split and roast small game, or how to use a butter churn.

    If you are seriously interested in math, you are bound to find the slide rule intriguing.

    Aside from idle curiosity, it is also true that taking the difficulty out of processes is not always an unmixed blessing, especially in education.

    My daughter just started middle school, and one of the key math skills she is being taught is "number sense". This topic basically amounts to cognitive strategies for looking at a set of calculations and determining if certain possible results are reasonable. What is interesting is that this hole in math education was left by the removal of the slide rule from the curriculum.

    The brain is a curious and largely unreasonable thing; it obstinately refuses to work in ways that seem like it should, yet performs brilliantly in ways it seems impossible that it might. For example, when I was a student, I experimented with using a tape recorder instead of taking notes, on the theory I could play the lecture back during what otherwise was down time. Aside from the obvious deficiencies of only having audio, I was disappointed to discover that at least for me, listening over and over to information doesn't do anything for recall. On the other hand, I was delighted to find that if I wrote down information as I heard it, mainly concentrating on the speaker but letting my hands semi-automatically follow along, my recall was so improved I seldom needed to refer to the notes I was taking. Something about the process of completing the circuit from input to output caused the information to stick.

    In many other instances, I have found that trivial manual effort has unexpected rewards. I recently wanted to review probability theory, and I found it helpful to work through even trivial problems that I could see how to solve right away. It wasn't enough to have the insight, doing the work improved my comprehension and retention.

    The lessons in number sense given by the slide rule are largely of the same kind. You'd think you could do as well having a superior calculating tool that effortlessly gives you more precision than you need. All you need to do is ignore the superfluous digits. It may even work that way for you, but I suspect many people's brains won't acquire the same skills.
  • Re:Um No. (Score:2, Insightful)

    by JSC ( 9187 ) <johnNO@SPAMcoxen.com> on Friday September 28, 2007 @02:17PM (#20785551)
    A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects.

    -Robert A. Heinlein
  • Re:Of course (Score:0, Insightful)

    by Anonymous Coward on Friday September 28, 2007 @02:22PM (#20785637)
    Yeah, nobody wants to beat up a gay liar.
  • Re:uh, no. (Score:2, Insightful)

    by Chris Tucker ( 302549 ) on Friday September 28, 2007 @05:12PM (#20788079) Homepage
    And when your computer crashes due to hard drive problems, power supply blows up, motherboard fries, etc, etc, etc, then what? "oh, sorry Professor, the computer is dead and I can't do that bigass math problem until the computer is fixed. Can you get the trolls in IT to hurry up and fix it?"

    Are there really people who read Slashdot who can't see the pleasure in learning something new, nor can they see the potential benefit in learning how to use something like the sliderule?

    I can't imagine how intellectually pathetic they must be.

IN MY OPINION anyone interested in improving himself should not rule out becoming pure energy. -- Jack Handley, The New Mexican, 1988.