Here is what wikipedia says, regarding formulas for Reclining-Declining sundials:
"In fact it is only in the last decade that agreement has been found on the correct hour angle formula for this type of dial. [...] Previous formulae given by Rohr and Mayall are not correct." That wikipedia statement is demonstrably, preposterously, ridiculously incorrect. I deleted it, and one of the wikipedists immediately re-posted it. As I mentioned before, the wikipedia article, in its notes at the bottom of the page, in note (b), shows some formulas from Mayall & Mayall--the ones that wikipedia says are incorrect. And, as I mentioned, I tried those formulas, and they gave the correct answer--right down to the calculator's last digit--for the hour-line position for the two times of day that I I input (8:00 a.m. and noon), for a Reclining-Declining dial. Wikipedia has a firm policy against having any statements without citation, but the abovequoted statement is in the wikipedia Sundial article without any citation. Evidently the wikipedist who re-posted that statemet wants the wikipedia Sundial article to remain a laughingstock. Michael Ossipoff ~ 26 N, 80W
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