On Mon 2017-12-04T10:37:35-0800 Paul Eggert hath writ:
Come to think of it, it's worth documenting the Dublin/Dunsink issue a bit more, including the question whether DMT was -00:25:21.1 or -00:25:22. It's possible that we're missing an 0.9-second transition for Dublin/Dunsink circa 1896, which presumably we'd model as a 1-second-transition! I'll leave that just as a comment for now. I installed the second attached patch, plus the third to fix a typo.
Thumbing through early issues of Bulletin Horaire, the journal of the International Time Bureau (BIH), quickly shows that actual times provided by observatories as the legal times for various jurisdictions commonly had varying offsets of many tenths of seconds from the intended times indicated by official documents. There are not many contenders for a more boring publication than the nearly 100 years of tabulations of how wrong various official clocks have been, but nestled in the introductions to each issue there are other passing references about when various observatories changed their rules, algorithms, and/or conventional longitudes and thus had a leap in the time they provided to their region. -- Steve Allen <sla@ucolick.org> WGS-84 (GPS) UCO/Lick Observatory--ISB 260 Natural Sciences II, Room 165 Lat +36.99855 1156 High Street Voice: +1 831 459 3046 Lng -122.06015 Santa Cruz, CA 95064 http://www.ucolick.org/~sla/ Hgt +250 m