On Sat, 16 Mar 2002, Frank Evans wrote:

> I recall reading somewhere that dialists in centuries gone by commonly
> used the pole star to align wall dials and that their equipment
> consisted of lengths of string and a candle. Can anyone throw any light
> on this? Obviously when setting up a dial on the south wall of a church,
> for instance, the dialist would have to be well away from the church to
> see the pole star. But why the candle?
> 
> Frank 55N 1W

Well, I could go to the building superintendant, and say "I'll give you
this fine candle, if you loan me the building lot plans." Then tie up the
bundle of plans with the string.  Or maybe that was another problem...

How about stretching the strings so as to create a sight-line to Polaris,
then using the candle as a point light source, project the shadow of the
string laterally, into the space to the South side of the building? It's
not completely clear in my mind, but something along those lines should
work.

Dave
37.29N 1211.97W

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