On 2025-07-21 00:39, Gent, R.H. van (Rob) wrote:
The most recent issue of the Annuaire on Gallica (2021) only lists information for Francehttps://gallica.bnf.fr/ark:/12148/bpt6k9127672b/f52.item (with a sourced list of day light savings from 1916 to 2020)
Thanks for the citation. It agrees with TZDB's Europe/Paris except for spring 1923, where things were chaotic and I see some evidence that TZDB is right and the Annuaire is wrong. Perhaps someone who knows French could get to the bottom of what happened to Parisian clocks in spring 1923.
In the meantime I adjusted comments to note the discrepancies by installing the attached proposed patches. The first proposed patch updates related commentary from Brazil's Divisão de Serviços da Hora (DISHO), which seems to have changed its name and acronym. The second proposed patch notes the spring 1923 disagreement between TZDB and the Annuaire and cites the New York Times report about Raymond Poincaré.
I was surprised to see that the 2020 Annuaire is the current edition. Have they stopped publishing it?
From bd6211293e10d69894bcc1575347af8b1210a7c9 Mon Sep 17 00:00:00 2001 From: Paul Eggert <[email protected]> Date: Mon, 21 Jul 2025 08:22:23 -0700 Subject: [PROPOSED 1/2] =?UTF-8?q?DSHO=20=E2=86=92=20DISHO?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit * europe: Adjust to renaming of DSHO to DISHO. Update comments referring to DSH, the name before DSHO. Omit commentary about a mistake in DSHO, as the DSHO data are a bit questionable and we needn’t go into the details about why we use better data. --- europe | 16 +++++++--------- 1 file changed, 7 insertions(+), 9 deletions(-) diff --git a/europe b/europe index df334fc2..f1dfe99e 100644 --- a/europe +++ b/europe @@ -54,7 +54,7 @@ # Десятая гос. тип., 1919. # http://resolver.gpntb.ru/purl?docushare/dsweb/Get/Resource-2011/Byalokoz__E.L.__Novyy__schet__vremeni__v__techenie__sutok__izd__2(1).pdf # -# Brazil's Divisão Serviço da Hora (DSHO), +# Brazil's Divisão de Serviços da Hora (DISHO) # History of Summer Time # <http://pcdsh01.on.br/HISTHV.htm> # (1998-09-21, in Portuguese) @@ -914,7 +914,7 @@ Rule Belgium 1922 1927 - Oct Sat>=1 23:00s 0 - Rule Belgium 1923 only - Apr 21 23:00s 1:00 S Rule Belgium 1924 only - Mar 29 23:00s 1:00 S Rule Belgium 1925 only - Apr 4 23:00s 1:00 S -# DSH writes that a royal decree of 1926-02-22 specified the Sun following 3rd +# DISHO writes that a royal decree of 1926-02-22 specified the Sun following 3rd # Sat in Apr (except if it's Easter, in which case it's one Sunday earlier), # to Sun following 1st Sat in Oct, and that a royal decree of 1928-09-15 # changed the transition times to 02:00 GMT. @@ -1383,7 +1383,7 @@ 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 +# DISHO 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 & Pottenger. Rule France 1922 1938 - Oct Sat>=1 23:00s 0 - @@ -2096,12 +2096,10 @@ Zone Europe/Warsaw 1:24:00 - LMT 1880 # all clocks therefore having to be advanced or set back correspondingly ... # Rule NAME FROM TO - IN ON AT SAVE LETTER/S -# From Tim Parenti (2024-07-01), per Paul Eggert (1999-01-30): -# DSH writes in their history that Decreto 1469 of 1915-03-30 established -# summer time and that, "despite" this, the change to the clocks was not done -# every year, depending on what Spain did, because of railroad schedules. -# In fact, that decree had nothing to do with DST; rather, it regulated the -# sending of time signals. But we do see linkage to Spain in the 1920s below. +# From Tim Parenti (2024-07-01): +# Decreto 1469 of 1915-03-30 ... had nothing to do with DST; +# rather it regulated the sending of time signals. +# But we do see linkage to Spain in the 1920s below. # https://dre.pt/dr/detalhe/decreto/1469-1915-285721 # https://dre.pt/application/conteudo/285721 # -- 2.48.1
From e9ef7c6cad998ebee1ac4078b4274664f5f71c84 Mon Sep 17 00:00:00 2001 From: Paul Eggert <[email protected]> Date: Mon, 21 Jul 2025 10:53:10 -0700 Subject: [PROPOSED 2/2] Cite the French Annuaire * europe: Cite the Annuaire par le Bureau des Longitudes (thanks to Robert H. van Gent). --- europe | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/europe b/europe index f1dfe99e..69beb397 100644 --- a/europe +++ b/europe @@ -1310,6 +1310,13 @@ Zone Europe/Helsinki 1:39:49 - LMT 1878 May 31 # France # Monaco +# From Robert H. van Gent (2025-07-21): +# The most recent issue of the Annuaire [par le Bureau des Longitudes] +# on Gallica (2021) ... lists information for France +# https://gallica.bnf.fr/ark:/12148/bpt6k9127672b/f52.item +# From Paul Eggert (2025-07-21): +# Go with the 2020 Annuaire (published 2021) except as noted below. + # From Ciro Discepolo (2000-12-20): # # Henri Le Corre, Régimes horaires pour le monde entier, Éditions @@ -1371,7 +1378,6 @@ Zone Europe/Helsinki 1:39:49 - LMT 1878 May 31 # problems in Algiers, Monaco and Tunis. # -# Shank & Pottenger seem to use '24:00' ambiguously; resolve it with Whitman. # Rule NAME FROM TO - 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 - @@ -1385,7 +1391,13 @@ Rule France 1921 only - Oct 25 23:00s 0 - Rule France 1922 only - Mar 25 23:00s 1:00 S # DISHO 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 & Pottenger. +# were Apr 12 and Oct 5. Apparently spring 1923 was tricky: the New York +# Times (1923-05-16 p 12 c 2) reported that the Chamber of Deputies on May 15 +# "after a strong appeal by Premier Poincaré, consented at last to +# pass the bill authorizing daylight saving time for this year in +# France.... The bill must now go before the Senate ...". +# Use the 2020 Annuaire dates, except for spring 1923 where +# Shanks & Pottenger's May 26 seems more plausible. 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 -- 2.48.1
