\ The original Roman year is variously stated by historians at twelve and ten months : the latter seems the best supported, and the old year wanted January and February, and had Quinctilis and Sextilis in place of July and August : these two months yielded their names to those of the two emperors who reformed the calendar. Numa or Tar quin introduced what was meant for a lunar year of 355 days. The year is supposed to have been more assimilated to the solar year by the decemvirs ; but there is a great deal of discussion upon all these points, which would be quite out of place in anything but an historical article. In the year 45 u.e. the correction made by Julius Cesar, with the assistance of Sosigenes, was introduced, the preceding year having been lengthened into 445 days, in order probably that the now era might fall at the full moon following the shortest day. The pontifices maximi who came after Julius Cesar mistook the meaning of his cor rection ; by a bissextile every fourth year they thought was meant one every fourth year, counting the last bissextile, according to their inter pretation of Ctesar's rule, by which the fourth numbers beginning from 1 were made not 5, 9, 13, &c., but 4, 7, 10, fie. This was corrected by Augustus, when Pontifex Maximus in B. C. 8, who directed that three bissextiles from that date should be omitted (being as many as had been then superadded to Caesar's calendar in years preceding), and that the mistake should be avoided in future.
No further chronological difficulty occurred until the 3rd century, when disputes about the mode of determining Easter-day began to perplex the Christian world. It is commonly stated that the Council of Nice made that adjustment which lasted until the Gregorian reformation. This is not correct : the council, according to Eusebius and others, only ordained that all Christians should keep Easter on one and the same day. [EASTER.] The Gregorian reformation (so called ; we will not stop to give reasons for our protest against the word) was a consequence of the desire that the seasons should remain in the same months for ever. The Julian calendar gave a year which is too long at the rate of 3 days in 400 years nearly. At this rate, in 24,000 years midsummer and midwinter would have fallen in December and June. It was not so much to avoid this, as to keep the religions festivals in the same part of the year, that is, in the same kinds of weather, that the correction was insisted on by its advocates. The change had been discussed by individuals and even by councils during preceding centuries, and was finally decided on by Gregory SILL, with the authority of the council of Trent. In 1582 the reformation was carried into effect : ten days were struck out of the reckoning, that which would have been the 5th of October being denominated the 15th, so that the days 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 of October, 1582, never existed in Italy and Spain, which accepted the change as soon as it was decreed. Some other
countries, as France, which accepted it in the year 1582, but not so early, had to make their changes accordingly. See STYLE for the times of adoption in different countries.
There was one incorrectness about this part of tho change, Lut not of any detriment. The equinox fell, at the time of the Nicene council, on the 21st of March, and the suppression of ten (lays was meant to make the equinox vibrate between the 21st and 22nd. But in point of fact, the Alphonsine tables, which were consulted, are wrong by a clay in this matter, and eleven days should have been suppressed. The consequence is [l'Enzons Or REVOLUTION] that the equinox vibrates between the 20th and 21st of March.
Leaving out the parts of the Gregorian correction which relate to Easter, we proceed to the alteration of the mode of intercalation. This is as follows :—Every year whose number is divisible by 4 is leap-year, except only when the number ends with 00, in which case it is not leap-year, except when the preceding figures are divisible by 4. Thus 1900 is not leap-year, but 1600 is. If we take the most recent value of the length of the year, mean solar days, and apply the method in FRACTIONS, CONTINUED, we shall see that the excess of the real year above that of 365 clays is something less than 1 day iu 4 years, more than 7 in 27, less than 8 in 33," more than 39 in 161, and less than 242 in 999. This last excess, 212 days in 999 years, is so very correct, that it is most fortunate that Gregory's advisers did not know it, for they would in that case have adopted it and saddled our world with a most troublesome omission of intercalations for the benefit of posterity of 50,000 years hence. As it is, the excess of 1000 mean Gregorian year above as many of 365 days is days : it would have been nearer the truth had it been 212.242 days. Accord ingly 1000 mean Gregorian years are too long by about a quarter of a day ; more correctly, 3600 years give an error of a day. Delambre proposed that the Anni Domini 3600, 7200, 10,800, &e., should not be leap years, which they are to be in the Gregorian calendar. If the world should last till A.D. 3600, we hope the correction will be called by Delambre 's name ; if his memory should then have perished, still more will that of the prevent article, so that there is no use in pressing the point.
The European years have been made to begin at such different periods, that the historical inquirer is frequently puzzled. We have mentioned those which relate to our country in PERIODS OP REVOLU TION. The 25th of December, the 1st of January, the 1st of March, the 25th of March, and Easter, have all been in use.