Thanks, Fer, I understand your signal well. My earler message had a mistake in that I gave the declining angle of the wall as 30 deg but gave the style height and distance for a wall declining 60 deg. The reason is simply that I normally use the alignment or bearing of a wall for my calculations, not the full-face direction. This derives from my pocket calculator programme that I developed "n" years ago when I reinvented the wheel and made a sundial! I would hate to change it.
By the way, does anyone else still use a pocket calculator for sundial calculations? Don't sneer, please, remember that captains of space ships taking part in the moon landings had Hewlett-Packard calculators strapped to their legs so that if all else failed they could still get home. I wouldn't be surprised to learn that Mir had one on board, too. It would seem appropriate for that lovely dinosaur. Frank -- Frank Evans
