J R Stockton, ≥ 2014-04-20
Links within this site :-
- Merlyn Home Page
- Site Index, E-Mail, Copying
- This Page :-
- Other pages on this site :-
- Date :-
- Date and/or Time :-
- Time :-
- Easter, etc. :-
- The Year 2000 Problem : 1999→2000 :-
- Programming :-
- Executables :-
a general DOS date/time program
- LONGCALC, ZIP,
a DOS program with some long-date/time code
- Source code, for those and for others,
is also in the programs/ directory.
- Tables :-
There is a ZIPped snapshot including
these Date and Time pages (822kB+), taken on or after 2014-08-11;
unZIP it in an empty directory.
- General :-
- Seen :-
- Whitaker's Almanac
- A modern Encyclopaedia Britannica
- The Delphi Magazine #34 (Jun 1998), pub. iTec, UK
- The Delphi Magazine #?? (Jan 2001), pub. iTec, UK
"Mapping Time - The Calendar and its History",
OUP 1998, ISBN 0-19-850413-6 (now 2nd Edn, and pbk.).
Book & site include algorithms
site has errata (n
Site not found, 20110103
- David Ewing Duncan, "The Calendar", Fourth Estate 1999,
- Derek Howse, "Greenwich time", OUP 1980, ISBN 0-19-215948-8
- Sir Paul Harvey, "The Oxford Companion to English Literature",
4th Edn., OUP 1967, ISBN 0-19-886106-1, Appendix III, "The
Calendar", has information on the British Calendar covering the
Second Millennium. Gives the dates of Julian Easter for 1066 to 1752,
and of Gregorian Easter for 1583 to 2000; also
Regnal Years; etc.
- Not seen :-
- I hear that "Early English Books Online" (EEBO) has relevant
material, for those who can access it.
- Duncan Steel, "Marking Time: The Epic Quest to Invent the Perfect
Calendar", Wiley 2000 - said to be good.
At Google Books : Limited preview
- Nachum Dershowitz and Edward M. Reingold, "Calendrical Calculations",
Cambridge University Press, ISBN 0-521-56474-3
and "Calendrical Calculations, The Millennium Edition", 2001,
ISBN 0-521-77752-6, 0-521-77167-6 pbk - said to be good
- I have repeatedly read that
Algorithms" (2nd ed, Dec '98) by Jean Meeus, Willmann-Bell
Publishers, ISBN 0-943396-61-1, is a good reference
- Explanatory Supplement to the Astronomical Almanac, edited by
P. Kenneth Seidelmann, University Science Books, Sausalito, CA 94965,
- "Ten Divisions lead to Easter" in book
"Puzzles and Paradoxes" by T H O'Beirne (London 1965).
May differ from his 1961 article.
- Leap Year and Easter:-
- The Papal Bull
- The British Calendar Acts
- The Book of Common Prayer of the Church of England
(for after the change to Gregorian in 1752)
- any reputable encyclopaedia
- Leap Year :-
- Isaac Asimov, "More Tales of the Black Widowers", Chap. X, "Friday
- "Communications of the ACM, algorithm number 199, originally submitted
by Robert G. Tantzen in the August, 1963 issue (Volume 6, Number 8)"
The classifications are inexact; the order is somewhat arbitrary.
Note that the visibility of material at Google Books may depend on
- The Papal Bull Inter Gravissimas, the Six Canons,
and the Explicatio :-
gravissimas - Wikipedia
Gravissimas (Papal Bull) (1582) by Gregory XIII,
translated by Wikisource
- All Papal
Encyclicals - a list - links to Bluewaterarts for the Bull
Encyclicals of Pope Gregory XIII - links to Bluewaterarts for the Bull
- The Bull in
(E) at ecu.edu
- The Bull in
(LFE) at bluewaterarts
- The Bull at ISO, as at bluewaterarts
- The Bull in
plus Sequitur declaratio ..., at The Latin Library
- The Bull in German,
in "Chronologie und Kalender", Nikolaus A. Bär
- Images of pages of Opera Mathematica
Clavius (1612). The fifth volume includes the Compendium,
the Six Canons and Romani calendarij à Gregorio XIII.
P. M. restituti explicatio (1603)
- European Cultural Heritage Online (ECHO) has a much better copy
Romani Calendarii a Gregorio XIII. P. M. Restituti Explicatio
(URL from Al Petrofsky) (+).
Compared to Notre Dame's copy, this version is
better focused, in higher resolution, and in colour, and it also
has the benefit of being the original 1603 typesetting, rather than
the 1611/12 reprint in the Opera Mathematica. The page numbering and
chapter numbering are different.
- Opera Mathematica V at Google Books
- is access limited?
Lessons from reading Clavius - Anders O. F. Hendrickson, MN, USA
Clavius, SJ and his Gregorian calendar
- The British Calendar Acts :-
- Authoritative : search for "Calendar Act" in the
UK Statute Law Database
site for legislation as current (database published 2006-12-20) -
includes images (large) of "Prayer Book" material cited in Section
3 of the first Act, presently placed at the end of Section 6.
Direct : http://www.statutelaw.gov.uk/content.aspx?ActiveTextDocId=1516754
Currently (Jan 2010) its Easter Table pages do not agree with
the current Prayer Book -
- Office of Public Sector Information - like Database.
- The original Calendar Act of AD 1751 - as images, 16pp,
no Tables, Google Books.
- An act for regulating the commencement of the year; and for correcting
the calendar now in use, Statutes at Large 1765, with Easter tables, Google Books
- Also Statutes at Large 1765 - www.archive.org (pages drag)
- Gilbert Healton's site has
(N); copy of Act at
- Mark Brader's transcription
others seem to be copies of this
- Lex Scripta, Anthony J H Morris :-
- The Gregorian Reform :-
- Any remaining links in my pages :-
Other links may be found on specific pages.
- Some of the other Links on this page
- My The Date of Easter Sunday with links
at Some Easter Algorithm Writers,
and associated pages linked therefrom
- [sci.astro] Time (Astronomy Frequently Asked Questions)
- NMM, UK :
The date of Easter
- Clive Feather's
Whence Easter ?
(his site also has UK/BI postcodes, phones, rail information)
- Ronald Mallen's
Easter Dating Method
The Date of Easter, USNO
- Wikipedia -
Computus - includes history, theory, and Gauss & Meeus algorithms
- see also its Discussion
Wikisource - 1911 Encyclopædia Britannica/Calendar/Ecclesiastical Calendar - Easter
Easter algorithm, Simon Kershaw / Diocese of Ely
Calendar & Easter Topics - Overview,
Easter Date Algorithms, ff. - GM Arts, AU
- Marcos J. Montes :-
The Easter-Date FAQ
the dates of the Paschal Feast and Passover - John R Covert
de Paschate - Dionysius Exiguus
- READ ABOVE FIRST
Sun in the Church - BSc Thesis, Ng Yoke Leng, Singapore, 2002/3
Note : table dating error in Sec 6.1.1
The Book of Common Prayer: From the Original Manuscript Attached to the
Act of Uniformity of 1662, and Now Preserved in the House of Lords
(1892) - limited access
- The Book of
Common Prayer - a number of versions
- Book of Common Prayer (1765) - imaged - has Easter tables
- Book of Common Prayer (1815) - imaged - has Easter tables
- Coyne, G. V., Hoskin, M. A., and Pedersen, O.(Eds.) (1983).
Gregorian reform of the calendar: Proceedings of the Vatican
conference to commemorate its 400th anniversary, 1582-1982.
Vatican City: Pontifical Academy of Sciences, Specolo Vaticano.
Calculation of Easter - Holger Oertel - with Swedish Easter
- The Frequency Distribution of the Dates of Easter - includes
date history and calculation
- Kalender - Computus
- Herbert Metz
John Wallis and the Date of Easter is on pp.54-59 (PDF, 725kB)
Augustus de Morgan, "A Budget of Paradoxes", seek "EASTER DAY"
on p.353 : includes "summary which was printed in the Irish
Prayer-book of the Ecclesiastical Society.", pp.356-370. Its
algorithm seems of limited range.
- Détermination de la date de PAQUES
- A part of
The Annotated Book of Common Prayer, by John Henry Blunt.
Dutton, 1895. Contains Annexe Tables with wording as in the original
Act. Describes the Epact.
How ten divisions lead to Easter (Google Books) - T H O'Beirne,
New Scientist, No. 228, 30 March 1961, pp.828-9.
May differ from his 1965 book.
- Anglican Church of Canada -
Date of Easter
- Sites linked from this page for Leap Year
and elsewhere on this site
- Claus Tøndering's
Asked Questions About Calendars ("Calendar FAQ"),
and The Calendar Blog -
- L. E. Doggett's
and their History
- Albert Van Helden's
- Peter Meyer's
and the Gregorian Calendars
- Joe Mehaffey's
CALENDAR TRIVIA page (by Eric Werme)
- Hermetic Systems :-
- Dershowitz :-
- Karl T. Hagen,
A History of the Western Calendar
- Gilbert Healton,
Best Of Dates, The Worst Of Dates
- Henk Reints, The
Gregorian Calendar - Quick Calculations
- Lex Scripta, Anthony J H Morris,
Calendar Resources and Links
- Nikolaus A. Bär,
Date calculator for various calendars.
- At webexhibits, via :
- Via Barney Wol
- Programme Weeks
Wikisource - 1911 Encyclopædia Britannica/Calendar
- Bill Casselman, UBC :
Links to PDF - 1911 Encyclopædia Britannica/Calendar
- Gregorian Calendar
The Calendar: Its History, Structure and Improvement -
Alexander Philip, LL.B., F.R.S. Edin., CUP 1921 (In pbk, 2012, £20.99)
- Urs Oswald, 2008 (PDF 394kB)
- Measurements and Units - see in
Kaye & Laby Online
- Sites linked (some are also below) from :-
- NRC Canada :
- The Catholic Encyclopaedia, GENERAL CHRONOLOGY, at newadvent. Eras
- Will Linden :-
- R.H. van Gent's
Webpages on the History of Astronomy
- Eric W. Weisstein's pages, including :-
(TDB, TDT, ET, GAST, GMST, TAI, UTC, UT, UT0, UT1, etc.)
- Time Zones
- Greenwich 2000
- Richard B Langley,
A Few Facts
Concerning GMT, UT, and the RGO.
- My Links for ISO 8601
- In news:comp.risks, Risks Digest 19.14, 1997-05-14, quoting JRL -
via FTP Risks Digest or
And Times In Excel - with links
- For date and time in the PC,
"The Timing FAQ" by Kris Heidenstrom.
- In my Time Miscellany page -
Time Zone Links
International Earth Rotation Service, in France; IERS's
Leap Second bulletin.
- BIPM Home
- NPL, UK :-
Myers - History of legal time in Britain
- NMM, UK :-
- HMNAO : Universal Time
- Stephen Tonkin
- Time - relationships between Solar, Sidereal, UT, etc.
- Sci.astro FAQ :
Time (Astronomy Frequently Asked Questions) (3/9) - includes
GMT, UT, UT0, UT1, UT2, UTC, DUT1, ET, TT, TDT, TBT, TAI
- NRC, Canada
Time Services FAQ
- The US Naval Observatory (USNO) :-
- Time Service Department :-
Systems of Time
- an explanation of TAI, UT, UT0, UT1, UTC,
TT, TDT, TDB, TCG, & TCB; also JDN & MJD
- The Astronomical Applications
Department of the US Naval Observatory (USNO) has :-
- the U.S. National Earth Orientation Service, via
Earth Orientation Department
- Paul Schlyter
Time Scales - Steve Allen (Lick), exhaustive.
Time Links - and others, by John D. Hynes. JD, MJD, TJD, etc.
- Paul Nagai -
Internet Clocks, Counters, and Countdowns
- NTP : The Network Time Protocol
- Primoz Gabrijelcic :
Is The Simplest Thing - The Delphi Magazine, Jan 2001 (PDF 135kB)
© Dr J R Stockton
, near London, UK.
All Rights Reserved.
These pages are tested mainly with Firefox
and W3's Tidy
This site, http://www.merlyn.demon.co.uk/
is maintained by me