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Subject: Re: ex-meridian sights
From: Steven Wepster (wepster@XXX.XXX)
Date: Mon Feb 12 2001 - 10:12:42 EST
Your quote doesn't say that Table 24 gives the change per minute; it
says that it gives the change _in one minute from the meridian_ . The
change in altitude is not linear so that's why Table 25 was not
calculated using Correction = a X t/60. Apparently a second-order
extrapolation (ie, a formula involving the square of t) is considered
sufficient (I didn't look int that in detail). It is quite natural
that the correction formula does not contain a first order term (a
factor times t) because that would spoil the symmetrical change in
altitude before and after transit.
Regards, _Steven Wepster.
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