earth—hence its name (the moonth or month). This revolution occupies about twenty-nine and one half days. Twelve of these revolutions would oc- cupy nearly a year, and hence it is supposed that the year was divided into twelve months. But such a year, twelve lunar months, would lack some- thing over eleven days of the time re- quired for the earth to perform a full revolution around the sun. Various expedients were adopted to provide for this discrepancy, and some nations, by reason of this difficulty, are said to have abandoned the moon and the month altogether, and regulated their year by the course of the sun alone. It would seem that this arrangement was but temporary, however, since the month, being so convenient a period of time, has finally retained its place in the calendars of all nations. But instead of denoting a single revolution of the moon around the earth, it is now usually employed to denote an arbitrary number of days approximating to the twelfth part of a solar year.
The Jews for a long time adhered to the computation by lunar months, while the Egyptians had a month of thirty days, invariably, and added five days at the end of the year which they called supplemental days. The Greeks divided their months into three decades, while the Romans had a very different method of reckoning, which to us seems very inconvenient. Instead of counting the days of the month in their order, as the first, second, third, and so on, the Romans counted backward from three fixed days, or epochs—the calends, the nones, and the ides. The calends always fell upon the first of the month; the nones, in March, May, July, and October on the 7th; and the ides on the 15th; and in the remaining months, the nones on the 5th and the ides on the 13th. The calends, the nones, and the ides were each numbered one and the day before it two, and so on, running back to the next fixed day.
In those months when the nones came on the 5th the ides came on the 13th; but if the nones came on the 7th the ides came on the 15th, so that there were always eight days, as they numbered them, between the nones and the ides, and these were counted as the 8th, 7th, &c., before the ides, the ides being No. 1, the day before it 2, &c. Thus the nones were, as the term indicates, the ninth days before the ides. After passing the ides, the 13th or 15th of the month, the days were numbered as the 19th, 10th, 6th, &c., before the calends—the calends being 1, the day before it 2, &c. ; and from the calends they were numbered as the 6th, 3d, &c., before the nones, the none being No. 1, the day before it, 2, and so on, backward, to the calends.
In the month of January, for instance, the ides came on the 13th, the nones on the 5 th. The first day of the month was known as the calends, or the calandæ; the second as the fourth before the nones, and so on to the second before, which was known as pridie nonas; the fifth was the nonæ; the sixth would be the eighth before idus, and so on, down to the second before, which would be pridie idus, or the 12th of our month; the idus was the 13th, and the next day, our 14th, was the 19th before the calends of February, and so numbering down to the 2d before, which would be our 31st of January, which was pridie calandas of February. Some of their months had thirty days and others thirty-one, as we shall see.
In sub-divisions of time the year is usually next to the month—the period observed by all nations in computing the times of historical events, and in keeping dates. The year is either solar or civil. The solar year is the period of time in which the earth performs a revolution in its orbit about the sun, or passes from any point in the ecliptic to the same point again, and consists of three hundred and sixty-five days, five hours, forty-eight minutes, and forty-six seconds of mean solar time. The civil year is that which is employed in chronology, and
