Page:Catholic Encyclopedia, volume 3.djvu/824

 CHRONOLOGY

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CHRONOLOGY

years are always given according to N. S., but dates are otherwise left as they were originally recorded. Thus Queen Elizabeth is said to have died 24 March, 1603. Not till 1700 was the Gregorian reform ac- cepted by the Protestant States of Germany and the Low Countries, and not till 1752 by Great Britain, there being by that time a difference of eleven days between O. S. and N. S. Sweden, after some strange vacillation, followed suit in 1753. O. S. is still fol- lowed by Russia and other countries subject to the authority of the Greek Church, and their dates conse- quently are now thirteen days behind those of the rest of Christendom.

Julian Period. — The Christian Era has this disad- vantage for chronological purposes, that dates have to be reckoned backwards or forwards according as they are B. c. or a. d., whereas in an ideally perfect system all events would be reckoned in one sequence. The difficulty was to find a starting point whence to reckon, for the beginnings of history in which this should naturally be placed are those of which chron- ologically we know least. At one period it was at- tempted to date from the Creation (A. M. or Anno Mundi), that event being placed by Christian chro- nologists, such as Archbishop Usher, in 4004 b. c, and by the Jews in 3761 b. c. But any attempt thus to determine the age of the world has been long since abandoned. In the year 1583, however — that fol- lowing the Gregorian reform — Joseph Justus Scaliger introduced a basis of calculation which to a large ex- tent served the purpose required, and, according to Sir John Herschel, first introduced light and order into chronology. This was the Julian Period — one of 7980 Julian years, i. e. years of which every fourth one con- tains 366 days. The same number of Gregorian years would contain 60 days less. For historians these commence with the midnight preceding 1 January, 4713 B. c, for astronomers with the following noon. The period 7980 was obtained by multiplying to- gether 2S, 19, and 15, being respectively the number of years in the Solar Cycle, the Lunar Cycle, and the Roman Indiction, and the year 4713 b. c. was that for which the number of each of these subordinate cycles equals 1. [For a fuller explanation of this see Bond, " Handy Book " (ed. of 1875), p. 257.] The astronom- ical day is reckoned from noon to noon instead of from midnight to midnight. Scaliger calculated his period for the meridian of Alexandria to which Ptolemy had referred his calculation.

Other Eras. — Various eras employed by histori- ans and chroniclers may be briefly mentioned, with the dates from which they were computed.

The Chinese Era dates probably from 2700 B. c, and time is computed by cycles of sixty lunar years, each shorter by eleven days than ordinary solar years.

Era of Abraham, from 1 October, 2016 b. c.

Era of the Olympiads, 13 July, 776 B. c, and con- tinued to a. d. 396 (Olympiad 293).

Era of the Foundation of Rome, 21 April, 753 B. c.

Era of Nabonassar, 26 February, 747, the basis of all calculations of Ptolemy.

Era of Alexander, 12 November, 324 B. c.

Greek Era of Seleucus, 1 September, 312 B. c.

Era of Tyre. 19 October, 125 n. c.

Qesarian Era of Antioch, 9 August, 4S b. c, in- stituted to commemorate the battle "i Pharsalia.

Julian Era, 1 January, 45 B. c, instituted on the Julian reformation of the calendar.

Era of Spain or of the Caesars, 1 January, 38 b i

Era of Augustus, 2 September, 31 B.C., instituted to commemorate the Battle of Actium.

Egyptian Year, 29 August, 26 B.C., instituted on the

reformation of the 1\"\ ]•< mm e:ilendar by Augustus.

Era of Martyrs or of Diocletian, 29 August, a. d. 284, employed by laisebius and early ecclesiastical writers.

Era of the Armenians, 9 July, A. D. 552, commemo-

rates the consummation of the Armenian schism by their condemnation of the Council of Chalcedon.

Era of the Hegira, 16 July, a. d. 622, dates from the entrance of Mohammed into Medina after his flight from Mecca; its years arc lunar, of 354 days each, ex- cept in intercalary years, of which there are eleven in each cycle of thirty. In these there are 355 days.

Persian Era of Yezdegird III, 16 June, A. D. 632.

At the French Revolution it was determined to in- troduce an entirely new system of chronology, dating from that event and having no affinity with any pre- viously adopted. In the first form this was the Era of Liberty, commencing 1 January, 1789. This was replaced presently by the Republican Era, at first ap- pointed to commence 1 January, 1792, and after- wards 22 September, 1792. This was the date of the proclamation of the Republic, which coincided with the autumnal equinox, calculated on the meridian of Paris. The year was divided into twelve months of thirty days each, and the days into decades, weeks being abolished. The months had names given to them according to their seasonal character. The autumnal months (22 Sept. onwards) were: — Ven- demiaire (Vintage), Brumaire (Foggy), Frimaire (Sleety). Winter Months: — Nivose (Snowy), Plu- viose (Rainy), Ventose (Blowy). Spring Months: — Germinal (Budding), Ploreal (Flowery), Prairial (Meadowy). Summer Months: — Messidor (Harvest- ing), Thermidor (Torrid), Fructidor (Fruitful). As these months contained only 360 days, five jours com- planentaires were added at the end of Fructidor, offi- cially called Primidi. Duodi, Tridi, Quartidi, Quintidi, but commonly known as Sans-culottides. Olympic or leap years occurred every fourth year of the Republic, and had a sixth intermediary day called Sextidi. The period thus terminated was called Franciade. This calendar was enforced in France till 1 January, 1806, when it was abolished by Napoleon, and the use of the Gregorian calendar resumed.

Days of the Month and Week. — Various methods have been devised for ascertaining upon what day of the w r eek any given date falls. The best known is that of Dominical Letters, which has this disadvantage, that a table is usually required to find out what is the Dominical Letter for the year in question. Complica- tion is likewise caused by the necessity of passing from one letter to another in leap years, on reaching the intercalary day in February. The following method is free from these inconveniences, and can be worked without any reference to tables: —

The days of the week are numbered according to their natural order, viz. Sunday =1, Monday = 2, Tuesday = 3, Wednesday = 4, Thursday = 5, Friday = 6, Saturday =7. (At the time from which the Christian Era starts there were of course no weeks, such a measure of time not being known among the Greeks and Romans. Counting backwards, however, ac- cording to our present system, we can divide all time into weeks, and it is to be noted that in the Christian period the order of days of the week has never been interrupted. Thus, when Gregory XIII reformed the Calendar, in 15S2, Thursday,-! October, was followed by Friday, 15 October. So in England, in 1752, U ednesday, 2 September, was followed by Thursday, l I September. What we style 14 August, 1907, the Russians style 1 August, but both call it Wednesday.) For our present purpose the year commences with March; January and February being reckoned as the 11th ami 12th months of the preceding year: thus 29 February, when it occurs, is the hist day of the

year and causes no further disturbance. \s a matter of fact, it is found by computation that 1 March of the year known as A. !>. 1 was a Tuesday. Assign- ing to this year tin- figure 1 as its year number, to March the figure 1 as its month number, and adding these to 1. the day number of 1 March, we get 3, indi- cating Tuesday tile third day of the week. From this