Hi Anselmo &al,
In the dusty corner of a mail folder I found an old message that I still
wanted to respond to.
From: Anselmo Pérez Serrada <[EMAIL PROTECTED]>
To: "Sundial, Mailinglist" <[email protected]>
Subject: Back again on thick gnomons
Date sent: Tue, 12 Feb 2002 15:44:33 +0100
Hi there,
(This is a remark I passed to make two weeks ago and then I
forgot completely )
On 27th-JAN Rod Heil and Fer de Vries were discussing on
the thick-gnomon paradox, ie., the fact that sunrise hours and
sunset hours cross on the plate when the gnomon is thick so it
is not completely correct that these dials consist on two halves.
Do you remember?
Well, my remark is as follows: of course Rod and Fer are right
and therefore Waugh is wrong in figure 5.4 of his book (page 41).
Anyway this is a mistake I have seen in many sundials and maybe
it is beause the error on the hour read is neglectible.
Anselmo Pérez Serrada
I don't understand why Waugh would be wrong in fig. 5.4. He is so smart as
to include only hour lines from 6 am to 6 pm, and thereby avoids the common
error that was correctly signalled by you, Fer and Rod.
Kind regards,
Frans
======================
Frans W. Maes
53.1°N, 6.5°E
www.biol.rug.nl/maes/sundials/
Hi all,
Frans is *almost* right: I mistook the page number and I meant fig.
7.2 (in pag 60) as Mac just pointed out. I sent
immediately after that message these right values, but maybe they got
lost in the hyperspace.
Does anybody in the US know if there are new editions of this book with
this error corrected (and the logarithms
removed!)?
Best regards,
Anselmo
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