The year is divided into four periods or seasons, the recurrence of which is indicated by the increase or diminution of the daylight. Immediately after the winter solstice the days begin to increase, and by the time of the vernal equinox, or in other words, in ninety days and three hours, the day is equal in length to the night. After this, for ninety-four days and twelve hours, the days continue to increase, and the nights to diminish in proportion, up to the summer solstice; and from that point the days, though gradually decreasing, are still in excess of the nights for ninety-two days, twelve hours, until the autumnal equinox. At this period the days are of equal length with the nights, and after it they continue to decrease inversely to the nights until the winter solstice, a period of eighty-eight days and three hours. In all these calculations, it must be remembered, equinoctial[427] hours are spoken of, and not those measured arbitrarily in reference to the length of any one day in particular. All these seasons, too, commence at the eighth degree of the signs of the Zodiac. The winter solstice begins at the eighth degree of Capricorn, the eighth[428] day before the calends of January, in general;[429] the vernal equinox at the eighth degree of Aries; the summer solstice, at the eighth degree of Cancer; and the autumnal equinox at the eighth degree of Libra: and it is rarely that these days do not respectively give some indication of a change in the weather. These four seasons again, are subdivided, each of them, into two equal parts. Thus, for instance, between the summer solstice and the autumnal equinox, the setting of the Lyre,[430] on the forty-sixth day, indicates the beginning of autumn; between the autumnal equinox and the winter solstice, the morning setting of the Vergiliæ, on the forty-fourth day, denotes the beginning of winter; between the winter solstice and the vernal equinox, the prevalence of the west winds on the forty-fifth day, denotes the commencement of spring; and between the vernal equinox and the summer solstice, the morning rising of the Vergiliæ, on the forty-eighth day, announces the commencement of summer. We shall here make seed-time, or in other words, the morning setting of the Vergiliæ, our starting-point;[431] and shall not interrupt the thread of our explanation by making any mention of the minor constellations, as such a course would only augment the difficulties that already exist. It is much about this period that the stormy constellation of Orion departs, after traversing a large portion of the heavens.[432] CHAP. 60.—THE PROPER TIME FOR WINTER SOWING.