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 is directed. In like manner it is easy to see that when a vessel is sailing away from the port, the beacons seem gradually to draw in together. This consideration provides us with the means of discovering the point in the sky towards which the motion of the sun is directed. We expect that point to be indicated by the circumstance that the stars appear to be spreading away from it.

The correctness of the inference that this is the spot towards which the system is moving will be confirmed, if at the same time it be noticed that the stars are drawing in towards that point in the celestial sphere which lies diametrically opposite. This investigation has been conducted with extreme care. Many astronomers, beginning with William Herschel, have applied themselves to its solution. The most complete investigation is that recently undertaken by Herr Stumpe. He has employed a very large number of stars, and he has adopted every precaution to insure accuracy in the results. Means are provided to enable the precision of his determinations to be properly tested. Stumpe has divided the stars used in his inquiry into four different groups, and he has obtained an independent determination from each of these groups. It is naturally of much interest to inquire where the point in the heavens is situated towards which, at the present time, the solar system appears to be wending its way. Each of the four groups which Stumpe employed has given him a distinct determination. The several investigations agree in locating the point within the limits of the constellation Lyra, adjoining that region of Hercules in which the earlier and less complete investigation of the same problem had located the apex of the sun's way. One of the four points lies actually at the wonderful double-double Epsilon