slide rules

[Rick Nekus]

My Uncle , a long-retired Consttruction Engineer used a "slide-rule" to estimate the quantity/mixture/plasiciity/...
of ALL the concrete needed for the building of the John Hancock building in Chicago with nothing but a "Slide-Rule". !
-NO, I kid you not. His results? -its still standing. -"NO" computers needed. Of course he had a few decades of experience with concrete prior.
 
yup, and he still likes to remind me of that fact, and ya, I do have some links now to prove it.
:)
-whatever can work.
> Date: Mon, 19 May 2008 13:52:09 +1000> From: grog at FreeBSD.org> To: saltmiser at gmail.com> CC: freebsd-chat at freebsd.org> Subject: Re: slide rules> > On Sunday, 18 May 2008 at 17:18:30 -0400, Jim Capozzoli wrote:> > So, I pulled out the slide rule yesterday that's older then I am..and> > I figured out how to multiply/divide on it. Is there anybody out> > there still using slide rules for day to day math? Or does anybody> > have any interesting stories/reminiscences about slide rules? I was> > considering figuring out how to do Trig on it and then taking my Trig> > final with it. :)> > Heh. I don't know where my slide rule is, but it's definitely a lot> younger than I am. So the following is from memory. It applies to> the conventional slide rules that I know, with C/D scales going from 1> to 10 at the bottom, and A/B scales going from 1 to 100 at the top> (giving squares of the corresponding scale below).> > To multiply two numbers, you place the 1 on the C scale (bottom of the> slide) against the first number on the D scale (directly below on the> body). Move the cursor (or your eye :-) to the second number on the C> scale, and read off the result on the D scale.> > To divide one number by another, you place the divisor the C scale> above the dividend on the D scale. Read off the quotient on the D> scale below the 1 on the C scale.> > Greg> --> See complete headers for address and phone numbers.
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