>From 97fd2cd9639865cd230b25d70f649f4614a9bb05 Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Thu, 10 May 2018 15:41:46 -0700
Subject: [PROPOSED] Rewrite history of Macau to match decrees

(Thanks to P Chan.)
* NEWS: Mention this.
* asia (Macau, Asia/Macau): Rewrite history of Macau before 1981.
* tz-link.html (National histories of legal time): Link to SMG.  Sort.
* zone.tab, zone1970.tab: Use coordinates of Fortalezo do Monte
with longitude of Macau time before 1904.
---
 NEWS         |   6 +++
 asia         | 148 +++++++++++++++++++++++++++++++++++++++++++++------
 tz-link.html |   8 ++-
 zone.tab     |   2 +-
 zone1970.tab |   2 +-
 5 files changed, 146 insertions(+), 20 deletions(-)

diff --git a/NEWS b/NEWS
index 6094f59..05db756 100644
--- a/NEWS
+++ b/NEWS
@@ -11,6 +11,12 @@ Unreleased, experimental changes
     April 10.  Its DST transitions in 1986/91 were at 02:00, not 00:00.
     (Thanks to P Chan.)
 
+    Fix several issues for Macau before 1992.  Macau's pre-1904 LMT
+    was off by 10 s.  Macau switched to +08 in 1904 not 1912, and
+    temporarily switched to +09/+10 during World War II.  Macau
+    observed DST in 1942/79, not 1961/80, and there were several
+    errors for transition times and dates.  (Thanks to P Chan.)
+
   Changes to build procedure
 
     New 'make' target 'rearguard_tarballs' to build the rearguard
diff --git a/asia b/asia
index 1821be6..bc250b4 100644
--- a/asia
+++ b/asia
@@ -767,24 +767,140 @@ Zone	Asia/Taipei	8:06:00 -	LMT	1896 Jan  1
 			8:00	Taiwan	C%sT
 
 # Macau (Macao, Aomen)
+#
+# From P Chan (2018-05-10):
+# * LegisMac
+#   http://legismac.safp.gov.mo/legismac/descqry/Descqry.jsf?lang=pt
+#   A database for searching titles of legal documents of Macau in
+#   Chinese and Portuguese.  The term "HOR��RIO DE VER��O" can be used for
+#   searching decrees about summer time.
+# * Archives of Macao
+#   http://www.archives.gov.mo/en/bo/
+#   It contains images of old official gazettes.
+# * The Macao Meteorological and Geophysical Bureau have a page listing the
+#   summer time history.  But it is not complete and has some mistakes.
+#   http://www.smg.gov.mo/smg/geophysics/e_t_Summer%20Time.htm
+# Macau adopted GMT+8 on 30 Oct 1904 to follow Hong Kong.  Clocks were
+# advanced by 25 minutes and 50 seconds.  Which means the LMT used was
+# +7:34:10.  As stated in the "Portaria No. 204" dated 21 October 1904
+# and published in the Official Gazette on 29 October 1904.
+# http://igallery.icm.gov.mo/Images/Archives/BO/MO_AH_PUB_BO_1904_10/MO_AH_PUB_BO_1904_10_00025_Grey.JPG
+#
+# Therefore the 1911 decree of Portugal did not change time in Macau.
+#
+# From LegisMac, here is a list of decrees that changed the time ...
+# [Decree Gazette-no. date; titles omitted in this quotation]
+#	DIL 732 BOCM 51 1941.12.20
+#	DIL 764 BOCM 9S 1942.04.30
+#	DIL 781 BOCM 21 1942.10.10
+#	PT 3434 BOCM 8S 1943.04.17
+#	PT 3504 BOCM 20 1943.09.25
+#	PT 3843 BOCM 39 1945.09.29
+#	PT 3961 BOCM 17 1946.04.27
+#	PT 4026 BOCM 39 1946.09.28
+#	PT 4153 BOCM 16 1947.04.10
+#	PT 4271 BOCM 48 1947.11.29
+#	PT 4374 BOCM 18 1948.05.01
+#	PT 4465 BOCM 44 1948.10.30
+#	PT 4590 BOCM 14 1949.04.02
+#	PT 4666 BOCM 44 1949.10.29
+#	PT 4771 BOCM 12 1950.03.25
+#	PT 4838 BOCM 43 1950.10.28
+#	PT 4946 BOCM 12 1951.03.24
+#	PT 5025 BO 43 1951.10.27
+#	PT 5149 BO 14 1952.04.05
+#	PT 5251 BO 43 1952.10.25
+#	PT 5366 BO 13 1953.03.28
+#	PT 5444 BO 44 1953.10.31
+#	PT 5540 BO 12 1954.03.20
+#	PT 5589 BO 44 1954.10.30
+#	PT 5676 BO 12 1955.03.19
+#	PT 5739 BO 45 1955.11.05
+#	PT 5823 BO 11 1956.03.17
+#	PT 5891 BO 44 1956.11.03
+#	PT 5981 BO 12 1957.03.23
+#	PT 6064 BO 43 1957.10.26
+#	PT 6172 BO 12 1958.03.22
+#	PT 6243 BO 43 1958.10.25
+#	PT 6341 BO 12 1959.03.21
+#	PT 6411 BO 43 1959.10.24
+#	PT 6514 BO 11 1960.03.12
+#	PT 6584 BO 44 1960.10.29
+#	PT 6721 BO 10 1961.03.11
+#	PT 6815 BO 43 1961.10.28
+#	PT 6947 BO 10 1962.03.10
+#	PT 7080 BO 43 1962.10.27
+#	PT 7218 BO 12 1963.03.23
+#	PT 7340 BO 43 1963.10.26
+#	PT 7491 BO 11 1964.03.14
+#	PT 7664 BO 43 1964.10.24
+#	PT 7846 BO 15 1965.04.10
+#	PT 7979 BO 42 1965.10.16
+#	PT 8146 BO 15 1966.04.09
+#	PT 8252 BO 41 1966.10.08
+#	PT 8429 BO 15 1967.04.15
+#	PT 8540 BO 41 1967.10.14
+#	PT 8735 BO 15 1968.04.13
+#	PT 8860 BO 41 1968.10.12
+#	PT 9035 BO 16 1969.04.19
+#	PT 9156 BO 42 1969.10.18
+#	PT 9328 BO 15 1970.04.11
+#	PT 9418 BO 41 1970.10.10
+#	PT 9587 BO 14 1971.04.03
+#	PT 9702 BO 41 1971.10.09
+#	PT 38-A/72 BO 14 1972.04.01
+#	PT 126-A/72 BO 41 1972.10.07
+#	PT 61/73 BO 14 1973.04.07
+#	PT 182/73 BO 40 1973.10.06
+#	PT 282/73 BO 51 1973.12.22
+#	PT 177/74 BO 41 1974.10.12
+#	PT 51/75 BO 15 1975.04.12
+#	PT 173/75 BO 41 1975.10.11
+#	PT 67/76/M BO 14 1976.04.03
+#	PT 169/76/M BO 41 1976.10.09
+#	PT 78/79/M BO 19 1979.05.12
+#	PT 166/79/M BO 42 1979.10.20
+# Note that DIL 732 does not belong to "HOR��RIO DE VER��O" according to
+# LegisMac.... Note that between 1942 and 1945, the time switched
+# between GMT+9 and GMT+10.  Also in 1965 and 1965 the DST ended at 2:30am.
+
+# From Paul Eggert (2018-05-10):
+# The 1904 decree says that Macau changed from the meridian of
+# Fortalezo do Monteo, presumably the basis for the 7:34:10 for LMT.
+
 # Rule	NAME	FROM	TO	TYPE	IN	ON	AT	SAVE	LETTER/S
-Rule	Macau	1961	1962	-	Mar	Sun>=16	3:30	1:00	D
-Rule	Macau	1961	1964	-	Nov	Sun>=1	3:30	0	S
-Rule	Macau	1963	only	-	Mar	Sun>=16	0:00	1:00	D
-Rule	Macau	1964	only	-	Mar	Sun>=16	3:30	1:00	D
-Rule	Macau	1965	only	-	Mar	Sun>=16	0:00	1:00	D
-Rule	Macau	1965	only	-	Oct	31	0:00	0	S
-Rule	Macau	1966	1971	-	Apr	Sun>=16	3:30	1:00	D
-Rule	Macau	1966	1971	-	Oct	Sun>=16	3:30	0	S
-Rule	Macau	1972	1974	-	Apr	Sun>=15	0:00	1:00	D
-Rule	Macau	1972	1973	-	Oct	Sun>=15	0:00	0	S
-Rule	Macau	1974	1977	-	Oct	Sun>=15	3:30	0	S
-Rule	Macau	1975	1977	-	Apr	Sun>=15	3:30	1:00	D
-Rule	Macau	1978	1980	-	Apr	Sun>=15	0:00	1:00	D
-Rule	Macau	1978	1980	-	Oct	Sun>=15	0:00	0	S
-# See Europe/Lisbon for info about the 1912 transition.
+Rule	Macau	1942	1943	-	Apr	30	23:00	1:00	-
+Rule	Macau	1942	only	-	Nov	17	23:00	0	-
+Rule	Macau	1943	only	-	Sep	30	23:00	0	S
+Rule	Macau	1946	only	-	Apr	30	23:00s	1:00	D
+Rule	Macau	1946	only	-	Sep	30	23:00s	0	S
+Rule	Macau	1947	only	-	Apr	19	23:00s	1:00	D
+Rule	Macau	1947	only	-	Nov	30	23:00s	0	S
+Rule	Macau	1948	only	-	May	 2	23:00s	1:00	D
+Rule	Macau	1948	only	-	Oct	31	23:00s	0	S
+Rule	Macau	1949	1951	-	Apr	Sat>=1	23:00s	1:00	D
+Rule	Macau	1949	1950	-	Oct	lastSat	23:00s	0	S
+Rule	Macau	1951	only	-	Mar	31	23:00s	1:00	D
+Rule	Macau	1951	only	-	Oct	28	23:00s	0	S
+Rule	Macau	1952	1953	-	Apr	Sat>=1	23:00s	1:00	D
+Rule	Macau	1952	only	-	Nov	 1	23:00s	0	S
+Rule	Macau	1953	1954	-	Oct	lastSat	23:00s	0	S
+Rule	Macau	1954	1956	-	Mar	Sat>=17	23:00s	1:00	D
+Rule	Macau	1955	only	-	Nov	 5	23:00s	0	S
+Rule	Macau	1956	1964	-	Nov	Sun>=1	03:30	0	S
+Rule	Macau	1957	1964	-	Mar	Sun>=18	03:30	1:00	D
+Rule	Macau	1965	1973	-	Apr	Sun>=16	03:30	1:00	D
+Rule	Macau	1965	1966	-	Oct	Sun>=16	02:30	0	S
+Rule	Macau	1967	1976	-	Oct	Sun>=16	03:30	0	S
+Rule	Macau	1973	only	-	Dec	30	03:30	1:00	D
+Rule	Macau	1975	1976	-	Apr	Sun>=16	03:30	1:00	D
+Rule	Macau	1979	only	-	May	13	03:30	1:00	D
+Rule	Macau	1979	only	-	Oct	Sun>=16	03:30	0	S
+
 # Zone	NAME		GMTOFF	RULES	FORMAT	[UNTIL]
-Zone	Asia/Macau	7:34:20 -	LMT	1911 Dec 31 16:00u
+Zone	Asia/Macau	7:34:10 -	LMT	1904 Oct 30
+			8:00	-	CST	1941 Dec 21 23:00
+ 			9:00	Macau	+09/+10	1945 Sep 30 24:00
 			8:00	Macau	C%sT
 
 
diff --git a/tz-link.html b/tz-link.html
index 13a824d..b8b7944 100644
--- a/tz-link.html
+++ b/tz-link.html
@@ -744,13 +744,17 @@ hreflang="he">announcements (in Hebrew)</a>.</dd>
 <dd>The National Institute of Metrological Research maintains a
 <a href="http://www.nanospin.eu/res/tf/ora_legale_i.shtml">table of civil time
 (in Italian)</a>.</dd>
+<dt>Macao</dt>
+<dd>The Macao Meteorological and Geophysical Bureau maintains a
+<a href="http://www.smg.gov.mo/smg/geophysics/e_t_Summer%20Time.htm">history
+of summer time</a>. Unfortunately it is incomplete and has errors.</dd>
+<dt>Malaysia</dt>
+<dd>See Singapore <a href="#Singapore">below</a>.</dd>
 <dt>Mexico</dt>
 <dd>The Investigation and Analysis Service of the Mexican Library of
 Congress has published a <a
 href="http://www.diputados.gob.mx/bibliot/publica/inveyana/polisoc/horver/index.htm"
 hreflang="es">history of Mexican local time (in Spanish)</a>.</dd>
-<dt>Malaysia</dt>
-<dd>See Singapore <a href="#Singapore">below</a>.</dd>
 <dt>Netherlands</dt>
 <dd><a href="https://www.staff.science.uu.nl/~gent0113/wettijd/wettijd.htm"
 hreflang="nl">Legal time in the Netherlands (in Dutch)</a>
diff --git a/zone.tab b/zone.tab
index f92c919..bb56fa1 100644
--- a/zone.tab
+++ b/zone.tab
@@ -268,7 +268,7 @@ MM	+1647+09610	Asia/Yangon
 MN	+4755+10653	Asia/Ulaanbaatar	Mongolia (most areas)
 MN	+4801+09139	Asia/Hovd	Bayan-Olgiy, Govi-Altai, Hovd, Uvs, Zavkhan
 MN	+4804+11430	Asia/Choibalsan	Dornod, Sukhbaatar
-MO	+2214+11335	Asia/Macau
+MO	+221150+1133230	Asia/Macau
 MP	+1512+14545	Pacific/Saipan
 MQ	+1436-06105	America/Martinique
 MR	+1806-01557	Africa/Nouakchott
diff --git a/zone1970.tab b/zone1970.tab
index 2d90ed7..91d7a57 100644
--- a/zone1970.tab
+++ b/zone1970.tab
@@ -231,7 +231,7 @@ MM	+1647+09610	Asia/Yangon
 MN	+4755+10653	Asia/Ulaanbaatar	Mongolia (most areas)
 MN	+4801+09139	Asia/Hovd	Bayan-��lgii, Govi-Altai, Hovd, Uvs, Zavkhan
 MN	+4804+11430	Asia/Choibalsan	Dornod, S��khbaatar
-MO	+2214+11335	Asia/Macau
+MO	+221150+1133230	Asia/Macau
 MQ	+1436-06105	America/Martinique
 MT	+3554+01431	Europe/Malta
 MU	-2010+05730	Indian/Mauritius
-- 
2.17.0

