Thanks for putting the USNO unofficial time zone info on the Web; it has helped me compose proposed patches for the public domain time zone history database at <ftp://elsie.nci.nih.gov/pub/tzdata95k.tar.gz>. After comparing the USNO data to other sources, I have some questions and comments. I'd appreciate any information you can send me to clear up the questions, especially pointers to other sources. The tzdata history database relies heavily on Thomas G. Shanks, The International Atlas (3rd edition), San Diego: ACS Publications (1991), a source that is now 4 years old, so some of the discrepancies noted below are undoubtedly because the time zones or daylight savings rules have changed recently. But I thought I'd tell you about the discrepancies just in case. <http://tycho.usno.navy.mil/tzones.html> (1995-11-11) says: Antarctica: -2 hours (Local summer -3 hours) Which part of Antarctica is that? I have the vague impression that different research stations in Antarctica use different local times. (The South Pole is the most interesting case, of course.) Armenia: +4 hours (Local summer +5 hours) Shanks has Armenia switching to +3 (+4 summer) in 1991. Perhaps they've switched back? Argentina western prov: -4 hours Shanks says Argentina has always had just one time zone. Azerbajian: +3 hours Shanks has Baku at +3 (+4 summer). Perhaps they've stopped using daylight savings time? Brazil Acre: -4 hours (Local summer -5 hours) Brazil Atlantic Islands: -1 hours (Local summer -2 hours) Brazil East: -3 hours (Local summer -1 hours) These must be typos. Here are proposed fixes. Brazil Acre: -5 hours (Local summer -4 hours) Brazil Atlantic Islands: -2 hours (Local summer -1 hours) Brazil East: -3 hours (Local summer -2 hours) Chatham Island: +12.75 hours (Local summer +13.75 hours) Do you have a source for when the transition to and from summer time takes place? Cocos (Keeling) Islands: ( hours (Local summer ) hours) This is a typo. The 1989 USNO listing has Cocos at +6.5 hours. Cook Islands: -10 hours Shanks has Cook at -9.5 during summer. The 1989 USNO listing had two entries for Cook, one at -10, the other at -10 (-9.5 summer) like Shanks. Equitorial Guinea: +1 hours This should be `Equatorial Guinea'. French Polynesia: -10 hours French Polynesia covers several time zones; e.g. I think the Marquesas and Gambier are part of French Polynesia, and they are at -9.5 and -9, respectively. Georgia: +4 hours Shanks says Georgia has summer time, but this may have changed with the rules change late last year (see _The Economist_, 1994-11-19, page 60). Is there a better source for this? Greenland Scoresbysun: -1 hours (Local summer 0 hours) This should be `Scoresbysund'. Guinea Bissau: - hours (Local summer 0 hours) This should be `0 hours', with no summer time. Kazakhstan: +6 hours (Local summer +7 hours) Shanks says Alma-Ata switched to +5 (+6 summer) in 1991. Perhaps they've switched back? Kiribati: +12 hours The country of Kiribati covers several time zones. Perhaps you could change `Kiribati' to `Tarawa'. Kwajalein: -12 hours In comp.risks 14.87 <http://catless.ncl.ac.uk/Risks/14.87.html#subj2> (1993-08-26), Peter Neumann writes that Kwajalein changed to +12 hours on 1993-08-20. Libya: +2 hours Shanks has Libya at +1 (summer +2). Mexico Baja Calif Norte: -8 hours (Local summer -7 hours) Shanks has Ensenada, southern Baja, at -8 all year. Mongolia: +8 hours Shanks says Mongolia has 3 time zones: +7 (+8 summer), +8 (+9 summer), and +9 (+10 summer). Namibia: +1 hours (Local summer +2 hours) Nicaragua: -6 hours (Local summer -5 hours) Shanks has Namibia at +2 all year, and Nicaragua at -6 all year. If these have changed recently, do you know when it changed, and what the transition times are? Russian Federation zone two: +4 hours (Local summer +5 hours) This must be a typo; it should be `+3 hours (Local summer +4 hours)'. Scotland: 0 hours Shanks and other sources have Scotland at +1 in summer. Tajikistan: +6 hours Shanks has Tajikistan at +5 (+6 summer). Perhaps they've switched? Tunisia: +1 hours Shanks has Tunisia at +2 in summer. Perhaps they've stopped using DST? Turkmenistan: +5 hours Shanks has Turkmenistan at +6 during summer. Perhaps they've stopped using DST? Ukraine: +2 hours (Local summer +3 hours) Ukraine has multiple time zones. _The Economist_ (1994-05-28, page 45) reports that Crimea switched to +3 (summer +4) last year. Uzbekistan: +5 hours Shanks has Tashkent at +5 (+6 summer). Perhaps they've stopped using daylight savings time?