[EMAIL PROTECTED] wrote:
To: "Sundial Mail List" <[email protected]>; "BSS"
<[EMAIL PROTECTED]>
Sent: Wednesday, June 18, 2003 5:46 PM
Subject: A new term for The Glossary?


> Fellow Shadow Watchers,
>                        Most diallists are familiar with the Noon Gap that
occurs on a horizontal sundial with a thick style edge.  The fact that the
shadow 'swaps edges' at 6.0am and 6.0pm is also well understood.
>
> I'm currently designing a large horizontal sundial for Longyearbyen at 78°
12' north to be located on Spitsbergen in the Svalbard Island Group, where
it may well be 'the world's first heated sundial', permafrost and cabling
permitting.
>
> The sun at 78°N is above the horizon for several months continuously so
the dial must read for a full 24 hours and its only just now dawned on me
that the corollary of a 'Noon Gap' is a 'Midnight Overlap'.  i.e. With a
style edge of any significant thickness the half hours-ish either side of
midnight occupy the same space on a 24 hour dial.  Of course a similar
situation occurs with an 'overhung' gnomon at Noon at lower latitudes as has
been discussed on the SML before so I should have anticipated this.
>
> Is this a new term for The Glossary or too rare to be worth listing? ;-)
>
> Tony Moss

Two thoughts:
The term 'midnight', to describe a time of day when the sun is shining,
seems strange. Is that (in Norwegian) the word they use?
It would be unacceptably insular to think of the polar regions' needs as
rare. We happily accommodate the southern hemisphere which is a good deal
further away from most BSS members.

Chris Lusby Taylor
Newbury
51.4N, 1.3W

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