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Re: Summary of Bowditch Table 15
From: George Huxtable
Date: 2005 Jan 25, 21:11 +0000
From: George Huxtable
Date: 2005 Jan 25, 21:11 +0000
That was a masterly summary by Trevor of the outcome of the discussion about Table 15. Perhaps it's one of one of those topics that come round at 3-year intervals. Previous discussion can be found in the archives, between 11 and 14 April 2002, under the threadname "Bowditch Table 9". Thanks to Jim Thompson for reminding me that in that earlier thread I had, indeed, previously pontificated about exactly that same matter. That time I had arrived at the right answer, first go. It had completely slipped from my mind. Now, my mind must be that much duller, because this time round, the full explanation of the double-error in Bowditch evaded me. No doubt it's the effect of exceeding 70. This time, I'll be sure to pencil-in an amendment to my copy of Bowditch, as I should have done in 2002, to be- d = sqr{(tan A / .0002419 )^2 + ((H-h) / .7349)} - (tan A / .0002419) Thanks to Trevor for an interesting question. George, ================================================================ contact George Huxtable by email at george@huxtable.u-net.com, by phone at 01865 820222 (from outside UK, +44 1865 820222), or by mail at 1 Sandy Lane, Southmoor, Abingdon, Oxon OX13 5HX, UK. ================================================================