We who are placed midway between the Pole and the Equator, see a mixture of these two motions. Some stars seem to circle round and round, as all would do if we stood at the North Pole. Some stars seem to rise and set, as all would do if we stood at the Equator. So much for the seeming movements of the stars. But now, about their real movements. Are the stars fixed, or are they not? These seeming daily and yearly motions do not affect the question, being merely caused by our own motions. Trees and hedges may appear to move as we rush past them in a train, yet they are really fixed. [Illustration: CONSTELLATION OF ORION 50,000 YEARS FROM NOW.] During a long while, after it was found out that the quick, daily movements of all the stars in company were merely apparent, men believed that they really had no “proper motions”--that is, no movements of their own. For century after century the constellations remain the same. Hundreds of years ago the seven chief stars of the Great Bear shone in company as they shine now. Who could suppose that each one of those seven stars is hurrying on its path through space with a speed exceeding far that of the swiftest express-train? Yet so it is. Hundreds of years ago the grand group of Orion, with belt and sword, gleamed brilliantly night by night as it gleams in these days; and Cassiopeia had her W form, and Hercules and Draco and Andromeda were shaped as they are shaped still. Who would imagine that through those hundreds of years each star of these different constellations was hastening with more or less of speed along its heavenly road? Yet so it is. Cases have been decisively ascertained of stars changing their places among the other stars by a slow and gradual motion. Three of the most conspicuous of them--Sirius, Arcturus, and Aldebaran--have been proved, by the comparison of modern with some ancient observations, to have experienced a change of place to the southward, to the extent of more than the breadth of the moon in all the three. And during the period of accurate modern measurement, other instances have been ascertained of steady change of place by the effect of proper motion. But if the stars are thus rapidly moving in all directions, how is it that we do not _see_ them move? How is it that, night after night, year after year, century after century, even thousand years after thousand years, the shapes of the constellations remain unaltered? Suppose you and I were standing on the seashore together, watching the movements of scores of sea-craft, little boats and large boats, steamers, yachts, and ships. Suppose we stood through a full quarter of an hour looking on. Some might move, it is true, very slowly; yet their movements in every case would plainly be seen. There could be no possibility of mistaking the fact, or of supposing them to be “fixed.” Just so we see the nearer planets move. Little danger of our supposing them to be “fixed stars.”