CALENDAR. 



months to their propfr plae«, he took into the acfo.mt 90 

 dayi which had been !ort by the former method of reckon- 

 ing, and formed a year of I <, months, or 445 dnys, which, 

 on account of its quantity and dcfign, has been called " ihe 

 »far of confufion." Thi'i year termuiated, and the Julian 

 year c-nnmenced on the I ft day of Jiinury, D. C. 46. Froni 

 this epoch, the civil year and months were regulated by the 

 eourfe of the fun. The year of Numa being ic days (]<orttr 

 than the fohr year, two days were added by Juliiia C;vlar 

 to each of the months of January, Aujriift, and December, 

 and one to April, June, September, ard November. More- 

 over, as the annual revolution of the fun is completed m 

 361; days, and about fix hoiirJ, he made the ycp.r to C(mfill 

 ofj65'day3 for three years fnccelTively, and every fourth 

 year, of 3f>6, in order to comprehend the odd fix honr;:. 

 Accordingly, he ordained, that an intercalary day (hoidd 

 be added every fourth year, to the 2 ;d of Frbruary ; that 

 is, the 24th day, or fixth of the calends of March, was to 

 be twice reckoned ; and hence this year was called Bifrx- 

 tile, which fee. It is alfo ftyled " Leap-year," from its 

 leaping a day more that year, than in sf common year. 

 Hence it appears, that the Roman, called alfo the Julian 

 Calcnilar, from ito reformer Julius, is difpofed into quadri- 

 ennial f)eriod- ; of which the firll three years, which he 

 called communes or common, coniill of 365 days ; and the 

 fourth bljftxtlle. 



The rrgidations which Julius Cifar had e(labli(hed were 

 mifapplied by thofe who had the direftion of the calendar. 

 They intercalated every third, inllead of every fourth year ; 

 fo that, in the interval of 36 years, three days more than the 

 due number were inlerttd. This error, how^ever, was foon 

 perceived. For the correflion of it, Auguftus ordained, 

 that the intercal itions (hould be omitted in the following 

 years ; viz. in the 41ft, 4;th, and ^f/th of the Julian sra. 

 This form of the year, thus correfted, was adopted in Italy, 

 and in fevcral other provinces of the Roman empire. By 

 fome nations, the lunar year was retained, and the days and 

 months were reckoned by the eourfe of the moon. Modern 

 chronologers have ufed the Julian year, bcin^j a mcafure of 

 time extremely fimple, and fufficiently accurate : and to 

 this rtandard they refer all events that have happened from 

 the beginning of the world. 



The Julian year, however, though admirably adapted to 

 common ufe, was dill iniperfeft : for as the time in which 

 the fun performs his annual revolution is not exaftly 365 

 days fix hours, but 36^ days five hours, 48 minutes, and 

 5^ feconds, the civil year mud therefore have exceeded the 

 'olar year by 11 minutes, 14^ feconds; which, in the fpace 

 of about 130 years, amounted to a whole day ; and, confe- 

 quently, in 47450, years the beginning of the year would 

 have advanced forwards through ail the feafoiis ; and in 

 half this ii.terval of time, the fnmmer folflice according to 

 the calendar, would hdve fallen in the midll of winter, and 

 the earth have been covered with froft, when the bloom of 

 TCgetation was expcftcd. It cannot be imagined that Sa- 

 figenes was totally unacquainted wltli this error : thou<>-h he 

 probably thought it much fmaller than it is, and therefore 

 pegledted it. Among the firll of thofe who difcovcred the 

 iroperfeftions of the Julian calendar, were the venerable 

 Bede, about the year 730, Johannes de Saero Bofco, about 

 113 J, and Friar Bacon, about 1255. Thefe great men 

 had obferved, that the true equinox "preceded the civil one 

 by about a day in ijo years. Sofigenes, in the reign of 

 Julius Cifar, had obferved the vernal equinox on the :5th 

 day of March. At the council of Nice, held in 325, it was 

 fixed on the 2ift of March ; and from that time to the year 

 I j8j, when the next reformation was effeded, the error, 

 3 



?c 



•iccnmulated by this means, amomited to about 10 ityt i 

 fo that the vernsl equinox was now found to happen on the 

 1 Ith of Mirch, inftcad of the 2 1 ft, as it ought to hav« 

 done, if the Julian account had agreed with the eourfe of 

 the fun. Thisconftaiit anticipation of the equinox, which, 

 in the cmrfe of more than a thoufaiid years, had become 

 too confiderablc not to be noticid, was fiift rtprcfented to 

 the council, of Conftance and Latran by two cardittals, 

 Petnis ah AUiaco, and Cufa, who (bowed the eaufe of the 

 error, and the means of correAing it. In the year 1474. 

 pope Sixtus IV. being convinced of the ntceflity of a refor- 

 mation, fent for Regiomontaniis, a cehbrattd mathema. 

 ticiati of that period, to Rome, and prefentcd him to the 

 archbifliopric of Ratilbon, in order to engage him in thi» 

 undertaking. But a premature death prevcntinjSf his aflift- 

 ance, and no one being thought worthy to be hij fucceffor, 

 the projert was, for that time, fufpcndtd. Although the 

 nccefiity of fonie alteration was acknowledged, it was after 

 the lapfe of ico years that pope Gregory XIII. had the 

 honour of accomplifhing what feveral preceding pontiffs and 

 councils had attempted in vain. He invited to Rome a con- 

 fiderable number of mathematicians and aftrcnomers, em- 

 ployed 13 years in the examination of their fevcral formulae, 

 and, finally, gave the preference to the plan propofed by 

 Atoifius and Antoninus Lilius, two brothers of Verona. 

 He tranfmittcd copies of this plan, A. D. Xj77» to all ca- 

 tholic itates, academies, &c. A council of the moft learned 

 prelates was convened bf the pope, and the fubjeA being 

 finally fettled, a brief was publifhtd in the month of March, 

 A D. 158;, by which the tife of the ancient calendar was 

 entirely abrogated, and the new one fubftituted in its ttead, 

 called, from the pope's name, the GRECORiikN Calendar, 

 or New Stvle. 



The firft objcft of the reformers was to correft the errors 

 of the former method of reckoning, and to make the 

 length of the year agree more exaftly with the eourfe of 

 the fun. For fhis purpofc it was agreed, that the 10 days 

 which had been gained by the old account, fhould ba 

 taken from the month of Oftoher of the year then cur- 

 rent, and the equinox brought back to the 21ft of March, 

 as it had been fettled by the council of Nice. And, in 

 order to prevent the future recurrence of a nmilar variation, 

 it was ordered, that, inftead of making every hundredth year 

 a bifiextile, as was the cafe in the former method, every 

 four-hundredth year only fhould be confidertd as a biffextile, 

 and the reft be reckoned as common years. The length of 

 the folar year, and the time of the vernal equinox, were by 

 thefe means very accurately fettled ; for as a day was gain- 

 ed by the former method of reckoning, in every interval of 

 130 years, this was nearly equivalent to a gain of three days 

 m every interval of 400 years ; and, confequt ntly, by mak- 

 ing the years 1700, 1800, and 1900, to be comnwin years, 

 iiilterd of leap-years, the error arifing from the odd time 

 would be properly corrected. The great diffitalty, how- 

 ever, confifted -n making the lunar year agree with the 

 folar one, and in fett'ing the true time for the obfervance 

 of Eafter and other moveable feafts, whieh had been fubjett 

 to no fixed rule. It had been ordered by the Council of 

 Nice, that Eafter (hould be celebrated upon the firft Sua- 

 day, after the firft full moon, following the vernal equinox. 

 And in order to the due obfervance of this rule, it became 

 necefiary to know the days when the full moons would hap- 

 pen, in the eourfe of every year. But this knowledge wa» 

 not eafily obtained ; for the period of Mtton, which made 

 J9 years exaftly equal to 235 lunations, or revolution* of 

 the moonj was found to be too long by about one hour 

 and thirty-two minutes ; and, confequently, after j6 of thefe 



period* 



