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    Re: Learn to Love Logarithms
    From: John D. Howard
    Date: 2016 May 15, 18:20 -0700

    Frank,

    First of all,  thanks for the link - Scrap Paper.

    Second, about logarithms.  The logs of sin and cos are negative so the old navs added 10 to make positive numbers.  Still you were dealing with a decimel point and had to rember to drop the the 20s and 30s etc.  Why do you think the method of multplying by -100,000 was not used instead?

    Greg Rudzinski posted a sin, cos, log table that is very easy to use.  I have done sight reductions from the old Bowditch and other old texbooks and the -100,000 log table seems SO EASY compared to the +10 tables.  Do you know if anyone used simalar tables in the 19th C. or had no one thought of it?  I find that doing time sights with the sin, cos, log ( times -100,000) is fun.

    I have learned to love logarithms.

    John H.

       
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