Wikipedia says Mayall Mayall's, and Rorh's formulas are wrong.
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 --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Wikipedia says Mayall Mayall's, and Rorh's formulas are wrong.
Additionally, Mayall Mayall's formula (shown in the notes at the bottom of the wikipedia Sundial article) for the angle between the substyle and the line for noon, gives the right result for: Lat = 51.5 Inclination = 45 Declination = 45 degrees left of south Michael Ossipoff --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Wikipedia says Mayall Mayall's, and Rorh's formulas are wrong.
I should add that the correct result described above, with Mayall Mayall's formula for the angle between the substyle and the line for noon, is gotten when the decline-direction (D) is measured from north. So D is the azimuth that the dial is facing. Michael Ossipoff --- https://lists.uni-koeln.de/mailman/listinfo/sundial
Wikipedia says Mayall Mayall's, and Rorh's formulas are wrong.
Sorry, I didn't intend to start new thread; I'm adding something to my Mayall Mayall question-post: First, I thank Simon for the answer and link. I've decided to divulge the reason for my question about Mayall Mayall: The wikipedia Sundial article says that Mayall Mayall, and Rohr as well, published incorrect Reclining-Declining formulas. In fact, the wikipedia sundial article also says that only in the last decade has there been agreement on the formula for a Reclining-Declining sundial. Those claims aren't supported in the article. Are they correct? I invite dialists to check out those claims, and modify or delete them in the wikipedia article. As I said, the article can be edited, modified, or deleted by anyone, without membership, registration or log-in. And, in general, the wikipedia sundial article needs some input from dialists. Come on, let's (at least in part) start fixing that wikipedia article, which is surely many people's introduction to sundials. I like sundials, and I don't like to be contentious about a subject that I like. And the Internet already has too much contentiousnes. But should unsupported or incorrect statements that contradict everything previously published be at that introductory article? Michael Ossipoff --- https://lists.uni-koeln.de/mailman/listinfo/sundial