Dear Sirs, I'd like to give you my compliments for your enormous work in the time-zone file of the whole world. I am working on this file to obtain a second file for one of mine specific applications. Unfortunately I have found some little errors or I think that these are some errors. I'd like to explain these points. First of all
From a lot of specialist books (for example Le Corre's book or Gabriel's book) I receive the information that in France, in the year 1943, and precisely from October 4, there was a double daylight saving time. This fact is not present in your database as you can see lower:
# France # # Shanks seems to use `24:00' ambiguously; we resolve it with Whitman. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule France 1916 only - Jun 14 23:00s 1:00 S Rule France 1916 1919 - Oct Sun>=1 23:00s 0 - Rule France 1917 only - Mar 24 23:00s 1:00 S Rule France 1918 only - Mar 9 23:00s 1:00 S Rule France 1919 only - Mar 1 23:00s 1:00 S Rule France 1920 only - Feb 14 23:00s 1:00 S Rule France 1920 only - Oct 23 23:00s 0 - Rule France 1921 only - Mar 14 23:00s 1:00 S Rule France 1921 only - Oct 25 23:00s 0 - Rule France 1922 only - Mar 25 23:00s 1:00 S # DSH writes that a law of 1923-05-24 specified 3rd Sat in Apr at 23:00 to 1st # Sat in Oct at 24:00; and that in 1930, because of Easter, the transitions # were Apr 12 and Oct 5. Go with Shanks. Rule France 1922 1938 - Oct Sat>=1 23:00s 0 - Rule France 1923 only - May 26 23:00s 1:00 S Rule France 1924 only - Mar 29 23:00s 1:00 S Rule France 1925 only - Apr 4 23:00s 1:00 S Rule France 1926 only - Apr 17 23:00s 1:00 S Rule France 1927 only - Apr 9 23:00s 1:00 S Rule France 1928 only - Apr 14 23:00s 1:00 S Rule France 1929 only - Apr 20 23:00s 1:00 S Rule France 1930 only - Apr 12 23:00s 1:00 S Rule France 1931 only - Apr 18 23:00s 1:00 S Rule France 1932 only - Apr 2 23:00s 1:00 S Rule France 1933 only - Mar 25 23:00s 1:00 S Rule France 1934 only - Apr 7 23:00s 1:00 S Rule France 1935 only - Mar 30 23:00s 1:00 S Rule France 1936 only - Apr 18 23:00s 1:00 S Rule France 1937 only - Apr 3 23:00s 1:00 S Rule France 1938 only - Mar 26 23:00s 1:00 S Rule France 1939 only - Apr 15 23:00s 1:00 S Rule France 1939 only - Nov 18 23:00s 0 - Rule France 1940 only - Feb 25 2:00 1:00 S # The French rules for 1941-1944 were not used in Paris, # but were used in other places (e.g. Monaco). Rule France 1941 only - May 5 0:00 2:00 M # Midsummer # Shanks says this transition occurred at Oct 6 1:00, # but go with Denis.Excoffier@ens.fr (1997-12-12), # who quotes the Ephemerides Astronomiques for 1998 from Bureau des Longitudes # as saying 5/10/41 22hUT. Rule France 1941 only - Oct 6 0:00 1:00 S Rule France 1942 only - Mar 9 0:00 2:00 M Rule France 1942 only - Nov 2 3:00 1:00 S Rule France 1943 only - Mar 29 2:00 2:00 M Rule France 1943 only - Oct 4 3:00 1:00 S Rule France 1944 only - Apr 3 2:00 2:00 M Rule France 1944 only - Oct 8 1:00 1:00 S Rule France 1945 only - Apr 2 2:00 2:00 M Rule France 1945 only - Sep 16 3:00 0 - # Shanks gives Mar 28 2:00 and Sep 26 3:00; # go with Excoffier's 28/3/76 0hUT and 25/9/76 23hUT. Rule France 1976 only - Mar 28 1:00 1:00 S Rule France 1976 only - Sep 26 1:00 0 - # Shanks gives 0:09 for Paris Mean Time, and Whitman gives 0:09:05, # but Howse quotes the actual French legislation as saying 0:09:21. # Go with Howse. Howse writes that the time in France was officially based # on PMT-0:09:21 until 1978-08-09, when the time base finally switched to UTC. # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Europe/Paris 0:09:21 - LMT 1891 Mar 15 0:01 0:09:21 - PMT 1911 Mar 11 # Paris Mean Time # Shanks gives 1940 Jun 14 0:00; go with Excoffier's 14/6/40 22hUT. 0:00 France WE%sT 1940 Jun 14 23:00 1:00 C-Eur CE%sT 1944 Aug 25 0:00 France WE%sT 1945 Sep 16 3:00 1:00 France CE%sT 1977 1:00 EU CE%sT The second fact In Italy, in 1944, there was a double situation: in the northern cities of the Gothic line (around Bologna) daylight saving time was excluded on October 2. Instead, in the southern cities of Gothic line, this daylight saving time, was excluded on September 17. This historic reference has been proven by the Gazzetta Ufficiale (Official Government Journal). But this reference is not in your database. The third fact In Italy, after 1866, the whole nation was divided in three parts: the continental part, the Sicily part and the Sardinia part, with three different time zones. You can read about it in the Regio Decreto (king decree) number 3224 in the year 1866. But even this aspect is not present in your work. Now I am asking myself: maybe I have not read well or these notices could have beeen left out by you? But, if you have forgotten these items, it is even possible that there are many others items left out? Please, I have another little query for you: do you know a software or a DLL (library) that includes all the correct world time-zones? Or, is there, on the web, a more recent release or your database with these corrections about the examples that I have made before? Excuse me for disturbing you and I send you many regards and a Merry Christmas and a Happy New Year Ciro Discepolo www.cirodiscepolo.it discepol@tin.it