Autumn

(aw'tum.) [ L. autumn us, from auctus-augeo, to increase.) The third season of the year, which begins, in the northern hemisphere, on the day on which the sun enters Libera, that is, abt. the 22d of Sept., and continues while he is pa ing through the three signs, Libra, Scorpio, and Sag it tar i us. The ecliptic form of the earth's orbit prevents the four seasons from being equal in length; and the prece ion of the equinoxes causes them to vary a little from age to age. At present, the length of A. is 89 days, 16 hours, and 47 minutes. It is the time which the sun takes to pa from the autumnal equinox to the winter solstice. [s. 63]