Thank you to Joel, Fabio, and Bill.
Before I sent off my inquiry last night, I had got as far as deciding
the dial must be some kind of Foster-Lambert similar to the Herstmonceux
dial that Fabio mentioned, but I was still confused. I'm relieve to
learn that it's not related to an analemmatic
Hello Steve, I'll take a guess at this.
I think the dial is really a heliochronometer with an analemma, not an
analemmatic dial. I think the screws up top held a focusing lens or a
pinhole aperture that projected a beam on to an analemma on to the lower
plate. The analemma is not visible in that
dear Steve,
I did a search.
At first I realize that the dial has equiangle hours, so it seems to me,
if it is analemmatic sundial it means that the dial has the inclination
to get this condition (e.g. UK744 www.sundialatlas.net/atlas.php?sun=UK744).
This condition allows to turn the dial to
