Dear Frank, You present a splendid summary...
> The most likely explanation, it seems to me, was > proposed by Fer de Vries. Indeed so... > In other words, at 9.37 am the sun will be directly > over the style and the cited longitude is the hour > angle. This explanation has the added advantage that > no geographical longitude is involved... Hmmm. Surely it would be even better to say... This explanation has the added advantage that it DOES involve a geographical longitude... The Pl longitude is the geographical longitude where, at 12 noon local sun time, anyone way to the west in Hawkshead could see the shadow of the gnomon falling along the sub-style of this dial. Thus "longitude" has its conventional geographical meaning. Just think: pupils at Hawkshead Grammar School could be taken outside for a break and told to watch for when the shadow fell along the sub-style. "Look at that boys", the schoolmaster would say, "It is now 12 noon everywhere along the Pl longitude". This has been the best thread for a long time!! Frank King Cambridge, U.K. --------------------------------------------------- https://lists.uni-koeln.de/mailman/listinfo/sundial
