Now it has been found that five of these stars—_viz.,_ Merak, Phaed, Megrez, Alioth, and Mizar (with its comrade)—are moving with practically the same speed in an easterly direction, while the other two, Dubhe and Benetnasch, are simultaneously moving westward, the motions of Benetnasch being apparently more rapid. The consequence of these opposed motions is, of course, that the figure of the “Dipper” cannot always have existed and will not continue to exist. In the accompanying diagrams it has been thought interesting to show the relative positions of these seven stars, as seen from the point which the earth now occupies, both in the past and in the future. Arrows attached to the stars in the figure representing the present appearance of the “Dipper” indicate the directions of the motions and the distances over which they will carry the stars in a period of about five hundred centuries. The time, no doubt, seems long, but remember the vast stretch of ages through which the earth has passed, and then reflect that no reason is apparent why our globe should not continue to be a scene of animation for ten thousand centuries yet to come. The fact that the little star Alcor placed so close to Mizar should accompany the latter in its flight is not surprising, but that two of the principal stars of the group should be found moving in a direction directly opposed to that pursued by the other five is surprising in the highest degree; and it recalls the strange theory of a double drift affecting all the stars, to which attention was called in the preceding chapter. It would appear that Benetnasch and Dubhe belong to one “current,” and Merak, Phaed, Megrez, Alioth, and Mizar to the other. As far as is known, the motion of the seven stars are not shared by the smaller stars scattered about them, but on the theory of currents there should be such a community of motion, and further investigation may reveal it. [Illustration: Cassiopeia]