NavList:

Chuck Varney, thank you for your explanation, my words were clumsy and I think I made the same mistake as Edwin Pugsley (the designer and builder of the Sundial) and used the wrong angle in the triangle to get the angle of the Gnomon relative to the horizontal.

I wonder how many people have looked at the shadow on the Armillary Sundial, applied the equation of time and Daylight saving and then concluded that *they* must have miscalculated - because they can't equal "watch time" (apart from Solar Noon).

I wonder if Edwin Pugsley was ever told that his Sundial gave the wrong time!

I'm sure if Edwin Pugsley had seen your drawing Chuck - he would have made a sundial that gave the right solar time.

Frank_R was correct (as always ;-) in his initial observation of the Gnomon - well Gdone.

Regards, Geoff Hitchcox, Christchurch, New Zealand.