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I am a sundial. I'm prepared to bet
Your watch can't tell when the sun will set

I once heard Frank King talk about sundials in particular this very cool one, which measures Babylonian hours (hours since sunrise) and Italian hours (hours since sunset)

I am moving house and thinking about making my own, but none of the walls face exactly South. One of the walls faces approximately South-southeast (haven't measured exactly yet).

Would it still be possible to make a sundial like that? I understand it would be shaded for the last couple hours of the day (when the sun is in the west)

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up vote 3 down vote accepted

The questioner says that he once heard a Frank King talk and then asks about designing a sundial that indicates Babylonian Hours and Italian Hours when the dial doesn't face due south. The sundial that was the subject of Frank King's talk doesn't face due south either. I suggest the questioner gets in touch with Frank King who might be able to advise.

Frank King

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I observe that the questioner already appears to be in touch with Frank King through this website and I suggest that the advice is given on this website. I am sure it makes an interesting read which contributes to this site. – DeltaLima Apr 29 '13 at 12:07
-1 while entertaining, this doesn't answer the question. – Brandon Enright Apr 30 '13 at 4:27

A vertical sundial that doesn't face N, E, S, or W is called a vertical declining dial. Formulae are in the link.

I don't know if, for such dials, there is any inherent difficulty with Babylonian or Italian hours. Ask Frank King.

By the way, there is a staggering amount of information on sundials available on the Internet. One may start with the Wikipedia link provided above, or here.

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