196 POPULAR SCIENCE MONTHLY. 



contains the goal towards which the sun and planets are hastening 

 to-day. Even the speed of this motion has been subjected to measure- 

 ment, and found to be about ten miles per second. 



The objective point and the rate of motion thus stated, exact science 

 holds her peace. Here genuine knowledge stops; and we can proceed 

 further only by the aid of that imagination which men of science 

 need to curb at every moment. But let no one think that the sun will 

 ever reach the so-called apex. To do so would mean cosmic motion 

 upon a straight line, while every consideration of celestial mechanics 

 points to motion upon a curve. When shall we turn sufficiently upon 

 ill at curve to detect its bending? Tis a problem we must leave as a 

 rich heritage to later generations that are to follow us. The visionary 

 theorist's notion of a great central sun, controlling our own sun's way 

 in space, must be dismissed as far too daring. Bui for such a central 

 sun we may substitute a central center of gravity belonging to a 

 great system of which our sun is but an insignificant member. Then 

 we reach a conception that has lost nothing in the grandeur of its 

 simplicity, and is yet in accord with the probabilities of sober mechan- 

 ical science. We cease to be a lonely world, and stretch out the bonds 

 of a common relationship to yonder stars within the firmament. 



