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    Re: Traditional navigation by slide rule (correction)
    From: Lu Abel
    Date: 2016 Jan 11, 00:57 +0000
    Two (and a half?) small comments on Bob Gothe's note (which, because of its size I am not attaching):

    1.   I don't think making a rule out of aluminum would be an issue:

    a.  You're speaking of small changes in temperature (say, from room temp to the temperature of one's hands), not hundreds of degrees.

    b.  More important, as long as everything expands uniformly, accuracy would not change.

    2.  I don't think the range of calculations (1 to 1000 knots) would be an issue.   The "1" on a slide rule can stand for 1, 10, 100, or 1000.   What's important is relative values - a one knot set on an airplane traveling at Mach 1 is hardly worth noting, whereas us sailors would surely be concerned about a one not set at six knots.

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