Having once learned the constellations of the zodiac and, approximately, the line of the ecliptic, it is not necessary for the ordinary observer to keep in mind the exact location of the vernal equinox. It is, however, an important point for the student of mathematical astronomy. Beginning at this point, the ecliptic runs through Pisces in a northeasterly direction for about thirty degrees to Aries, the second constellation of the zodiac. ARIES Aries is best seen in the autumn when the sun is in the opposite side of the heavens. It is marked by a small acute-angled triangle, with the apex toward the north and the brightest star of the three at the apex. This star is called Hamal, and, while not a first-magnitude star, is a rather bright one of the second magnitude; and the triangle itself is very distinctly marked. It is the only group of stars by which to distinguish Aries, and it is sometimes confused with the little constellation called Triangulum, which lies just west of it, or above it, as it rises. With this in mind, Triangulum may be made to serve as an identifying mark. They both rise just a trifle north of the exact east early in the evenings of late September and October. Triangulum rises first, with its apex toward the south. In less than an hour the triangle of Aries arrives with its apex pointed north. The ecliptic runs about five degrees below this triangle, and its path across Aries is about twenty-eight degrees long. When one sees any very bright star in Aries, one may be sure it is a planet. The sun is in Aries from April 16th to May 13th. During the summer this constellation is not visible in the early evening; but it may be seen every evening from September to April, drawing all the time nearer to the sun, and setting earlier each evening until the sun blots it out. From this constellation the ecliptic runs into Taurus, the third zodiacal constellation. TAURUS This constellation may be identified by the brilliant first-magnitude star Aldebaran,[2] and the misty Little Dipper of the Pleiades. It is a very beautiful and large constellation. About an hour and a half after the triangle of Aries has risen, the soft-twinkling cluster of tiny stars which form the Pleiades comes above the eastern horizon, and about an hour later a V-shaped cluster of brighter stars, with a very bright-red one at the end of the lower half of the V, appears. This last cluster is the Hyades, and the bright star is Aldebaran. [2] See “Aldebaran” in _The Friendly Stars_.