At 13:47 7-6-00 -0700, you wrote:
-----Original Message/Oorspronkelijk bericht--------------
>
>  Why is there a gap in the wall, about noon (1300 Summer Time)?

Release of rain water, so no dirt will build up there.

>Above the gnomon, there appears to be a small pyramidal point, that would
>cast a shadow inside the bright spot, at local noon?

It is a screw with cap to fix the dialface in order to get the correct
longitude correction.

>Does the gnomon cylinder look tilted to anyone else? (Not perpendicular to
>the dial plate)

They are perpendicular.

>Very interesting design!
>
>Dave
>
>
>> From: Andrew James <[EMAIL PROTECTED]>
>> To: 'Steve Lelievre' <[EMAIL PROTECTED]>; Sundial mailing list
>> <[email protected]>
>> Sent: Wednesday, June 07, 2000 9:38 AM
>> Subject: RE: Water filled sundial at Herstmonceux
>> 
>> 
>> > There are a number of these around (the one I remember seeing is at the
>> > Manor House Museum, Bury St Edmunds) - it's a registered design but I
>> can't
>> > remember the details though I think it was 1960s or perhaps later.
>> > Basically the cylinder and liquid acts as a cylindrical lens which
focuses
>> a
>> > bright spot (the intersection of a bright line with the equatorial plane)
>> > onto the scale.  It only works in summer because it's an upper surface
>> > equatorial!  It would work with solid plastic or glass but I expect that
>> it
>> > is made like that because liquid filled is cheaper ...
>> >
>> > Andrew James
>> >
>> > -----Original Message-----
>> > From: Steve Lelievre [mailto:[EMAIL PROTECTED]
>> > Sent: 07 June 2000 16:29
>> > To: Sundial mailing list
>> > Subject: Water filled sundial at Herstmonceux, England, ...
>> > ...
>> > photo is at http://www.ualberta.ca/~droles/astro/astrav/Sun2.html
>
>
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