After reading the discussion about time around Ethiopian area, I am reminded that there is actually another clock that is in use for Chinese-speaking area [and maybe also some other neighboring region]. The system, nowadays mostly used in traditional customary/religious activity only, would divide a day into 12 "double hours" (it seems to be a common English translation for the original Chinese term), and then assign each double hour a name from "Earthly Branch". The tricky thing here is, the first hour "zi" actually start at 11 o'clock (pm) standard time. And so everyday start and end at 23:00 according to this system [However, note that some have suggested changing the system, so that despite the 'zi' hour still represent the time period between 11pm and 1am, in some's mind it would be broken into a 'early zi' hour that belong to the previous day while the second half of the hour would be treated as a 'late zi' hour that belongs to the second day]. Also, according to old calendar books, DST are not observed for the traditional timing system, so the "zi" hour would start at DST 24:00 if there's a DST. And then, nowadays there are people who directly use time that are keep officially according to timezone rules to convert time into this traditional system, however there are also people who use the local solar time instead.