Let us now say good-bye to Epigenes, and proceed to examine the 1 opinions of other writers. But before beginning to set them forth, I must first, by way of preface, remark that comets are not observed only in one part of the sky, nor merely in the zodiac, but in the east as well as in the west, more frequently, however, toward the north. Nor is 2 their shape uniform. The Greeks, indeed, distinguished three classes of them: those from which the flame hangs down, after the fashion of a beard; those that shoot out what looks like hair round them on all sides; and those which have a scattered kind of fire, which, however, stretches toward an apex.[92] But all the classes have a common characteristic, and are rightly called comets (_i.e._ long-haired). As the different shapes present themselves only at long intervals, it is difficult to compare them with one another. Even at the time of their appearance spectators are not agreed as to their shape. According 3 as one’s eyesight is keener or duller, one asserts that the comet is brighter or redder, and that its hair is compressed toward the interior of the star, or spread out toward its sides. But whether or not there are any differences in comets, they must all be produced by the same method. The one fact about which there ought to be agreement is, that 4 a star of strange unwonted appearance is beheld which drags along with it scattered fire. Some of the ancients are convinced of the truth of this explanation: When one of the planets has come into conjunction with another, the light of the two blends in one, producing the appearance of a more elongated star. This happens not merely when star touches star, but even when one approaches another. The space between the two is in that case lit up by both, and seems aflame, producing the trail of fire. [92] _I.e._ are cone-shaped. XII