72 



EPOCH. 



754 B. C. This era is designate,! by the letters, 

 A. U. C., or ab urbe condita (from the building of the 

 city). The first year used by them, and attributed 

 to Romulus, consisted of ten months from March to 

 December, or 304 days. (For an account of the 

 Roman mode of computing tune, see Calendar.) 

 The Roman year has been adopted by almost all 

 Ciiristian nations, with no oilier variation than taking 

 the birth of Christ as the commencement, instead of 

 the building of Rome. If the given Roman year be 

 h>s than 754, deduct it from 754 ; if the given Ro- 

 man year be not less tlian 754, deduct 753 from it ; 

 the remainder gives the year (B. C. and A. D., in 

 the first and second cases respectively) in which the 

 Roman year commences. Examples : 

 Required the year 780 A. U. C. 

 deduct 753 



27 A. D. 

 Required the year 701 A. U. C. 



From 754 

 deduct 701 



53 B. C. 



The Olympiads. The Greeks computed their time 

 by the celebrated era of the Olympiads, which date 

 from the year 776 B.C., being the year in which 

 Coroebus was successful at the Olympic games. This 

 era differed from all others in being reckoned by 

 periods of four years instead of single years. Each 

 period of four years was called an Olympiad; and, 

 in marking a date, the year and Olympiad were both 

 mentioned. The year was luni-solar, of twelve or 

 thirteen months. The names of the months varied 

 in the different states of Greece, but the Attic montlis 

 are most usual. (For a further account of the Greek 

 mode of computing time, see Calendar.) To reduce 

 the date by Olympiads to our era, multiply the past 

 Olympiad by four, and add the odd years ; subtract 

 the sum from 777 if before Christ, and subtract 776 

 from the sum if after Christ ; the remainder will be 

 the beginning of the given year. To decide on the 

 exact day would be very difficult, on account of the 

 alterations which the system has undergone. It will 

 be perhaps sufficient to observe, that the year begins 

 within a fortnight of the middle of July. N. B. Some 

 authors, as Jerome and Eusebius, have confounded 

 the Olympiads with the era of the Seleucides, and 

 computed them from the 1st of September. 



The Christian Era.- The Christian era used by 

 almost all Christian nations, dates from January 1st, 

 the middle of the fourth year of the 194th Olym- 

 paid, in the 753d of the building of Rome, and 4714th 

 of the Julian period. It was first introduced in the 

 sixth century, but was not very generally employed 

 for some centuries after. The Christian year, in its 

 division, follows exactly the Roman year ) consisting 

 of 365 days for three successive years, and of 366 in 

 the fourth year, which is termed leap year. This 

 computation subsisted for 1000 years, throughout 

 Europe, without alteration, and is still used by the 

 followers of the Greek church : other Christians have 

 adopted a slight alteration, which will be shortly 

 explained. The simplicity of this form has brought 

 it into very general use, and it is customary for 

 astronomers and chronologists, iii treating of ancient 

 time, to date back the same order from its commence- 

 ment. There is, unfortunately, a little ambiguity on 

 this head, some persons reckoning the year imme- 

 diately before the birth of Christ, as 1 B. C., and 

 others noting it with 0, and the second year 

 before Christ with 1, making always one less than 

 those who use the former notation. The first is the 

 most useful mode, and will be employed in all our 

 computations. The Christian year (or Julian year), 



arranged as we have shown, was 11' 11'' too long, 

 amounting to a day in nearly 129 years ; and, towards 

 the end ot the sixteenth century, the time of cele- 

 brating the church festivals had advanced ten days 

 beyond the periods fixed by the council of Nice, in 

 325. It was in consequence ordered, by a bull of 

 Gregory XIII., that the year 1582 should consist of 

 355 days only, which was effected by omitting ten 

 days in the month of October, viz., from the filth to 

 the fourteenth ; and, to prevent the recurrence of a 

 like irregularity, it was also ordered, that, in three 

 centuries out of four, the last year should be a com- 

 mon year, instead of a leap year, as it would have 

 been by the Julian calendar. The year 1600 re- 

 mained a leap year, but 1700, 1800, and 1900 were 

 to be common years. This amended mode of com- 

 puting was called the new style, and was immediately 

 adopted in all Catholic countries, while the old style 

 continued to be employed by other Christians. Gradu- 

 ally the new style was employed by Protestants also. 

 The last ten days of 1699 were omitted by the Pro- 

 testants of Germany, who, in consequence, began the 

 year 1700 with the new style ; and in England, the 

 reformed calendar was adopted in the year 1752, by 

 omitting eleven days, to which the difference between 

 the styles then amounted. The alteration was ef- 

 fected in the month of September, the day which 

 would have been the third being called the fourteenth. 

 The Russians continued to use the old style till the 

 year, 1830, when they adopted the new style. 



To turn the Old Style to the Nan. 



From the alteration of style to the 29th February, 1700, add 10 days. 

 From 1st of March, 1700, to 29th of February, 1800, "11 " 



1900, 



1900, 

 2)00, 



Etctmples. 



17th March, 1801, 0. S., is 29th March, 1801, N. S. 

 19th February, 1703, O. S., is 2d March, 1703, N. S. 

 24th December, 1690, O. S, is 3d January, 1691, N. S. 

 20th December, 1829, 0. S., is 1st January, 1830, N. S. 



There will sometimes be a difference of one year 

 in a date, from the circumstance that, in many coun- 

 tries, the time of beginning the year has varied. In 

 England, until the year 1752, the year was considered 

 to begin on the 25th of March : any date, therefore, 

 from the 1st of January to the 24th of March, will be 

 a year too little. It had been the practice, for many 

 years preceding the change of style, to write both 

 years, by way of obviating mistakes ; as, 1st of 

 February, 170^ or 1707-8, meaning the year 1708, 

 if begun in January, or 1707, if begun in March. In 

 some countries, Easter day was the first day of the 

 year ; in others, the 1st of March ; and in others, 

 again, Christmas day ; but no certain rule can be 

 given, as, even in the same nation, different provin- 

 ces followed a different custom. All nations, at pre- 

 sent using either the old or new style, begin the year 

 on the 1st of January. 



The Creation has been adopted as an epoch by- 

 Christian and Jewish writers, and would have been 

 found very convenient, by doing away with the diffi- 

 culty and ambiguity of counting before and after any 

 particular date, as is necessary when the era begins 

 at a later period. But, unfortunately, writers are 

 not agreed as to the precise time of commencing. 

 We consider the creation as taking place 4004 years 

 B. C. ; but there are about 140 different variations 

 in this respect.* The following are those that have 

 been most generally used : 



The Era of Constantinople. In this era the creation 

 is placed 5508 years B. C. It was used by the Rus- 

 sians until the time of Peter the Great, and is still 



* See Companion to the British Almanac for 1328, p. 49. 



