88 ASPECTS OF AMERICAN ASTRONOMY. 



we should place not far behiud the means ot subsistence. That we now 

 look upon a comet as somethin,i«- very interesting, of which the sight 

 affords us a pleasure uinuixed with fear of war, pestilence, or other 

 calamity, and of which we therefore wish the return, is a gain we can 

 not measure by money. In all ages astronomy has been an index to 

 the civilization of the people who cultivated it. It has been crude or 

 exact, enlightened or mingled with superstition, according to the cur- 

 rent mode of thought. When once men understand the relation of the 

 X^lanet on which they dwell to the universe at large, superstition is 

 doomed to speedy extinction. This alone is an object worth more than 

 money. 



Astronomy may fairly claim to be that science which transcends all 

 others in its demands upon the practical application of our reasoning 

 powers. Look at the stars that stud the heavens on a clear evening. 

 What more hopeless problem to one confined to earth than that of 

 determining their varying distances, their motions, and their physical 

 constitution ? Everything on earth we can handle and investigate. 

 But how investigate that which is ever beyond our reach, on which we 

 can never make an experiment? On certain occasions we see the moon 

 pass in front of the sun and hide it from our eyes. To an observer a 

 few miles away the sun was not entirely hidden, for the shadow of the 

 moon in a total eclipse is rarely 100 miles wide. On another continent 

 no eclipse at all may have been visible. Who shall take a map of the 

 world and mark upon it the line on which the moon's shadow will' 

 travel during some eclipse a hundred years hence? Who shall map 

 out the orbits of the heavenly bodies as they are going to appear in a 

 hundred thousand years"? How shall we ever know of what chemical 

 elements the sun and the stars are made? All this has been done, but 

 not by the intellect of any oue man. The road to the stars has been 

 opened only by the etfoi-ts of many generations of mathematicians and 

 observers, each of whom began where his predecessor had left oft". 



We have reached a stage where we know much of the heavenly bodies. 

 We have mapped out our solar system with great precision. But 

 how with that great universe of millions of stars in which our solar 

 system is only a sj)eck of star dust, a speck which a traveler through 

 the wilds of space might pass a hundred times without notice? We 

 have learned much about this universe, though our knowledge of it is 

 still dim. We see it as a traveler on a mountain top sees a distant 

 city in a cloud of mist, by a few specks of glimmering light from 

 steeples or roofs. We want to know more about it, its origin and its 

 destiny; its limits in time and space, if it has any; what function it 

 serves in the universal economy. The journey is long, yet we want, in 

 knowledge at least, to reach the stars. Hence we build observatories 

 and train, observers and investigators. Slow indeed is progress in the 

 solution of the greatest of problems, when measured by v»^hat we want 



