232 FRAGMENTS OF SCIENCE. 



lin black dresses are more potent than white ones as ab 

 sorbers of solar heat. 



Thus, in brief outline, I have brought before you a few 

 of the results of recent inquiry. If you ask me what is the 

 use of them, I can hardly answer you, unless you define the 

 term use. If you meant to ask me whether those dark 

 rays which clear away the Alpine snows will ever be ap 

 plied to the roasting of turkeys or the driving of steam- 

 engines, while affirming their power to do both, I would 

 frankly confess that they are not at present capable of 

 competing profitably with coal in these particulars. Still 

 they may have great uses unknown to me ; and when our 

 coal-fields are exhausted, it is possible that a more ethereal 

 race than ourselves may cook their victuals and perform 

 their work in this transcendental way. But is it necessary 

 that the student of science should have his labors tested by 

 their possible practical applications ? What is the prac 

 tical value of Homer s Iliad ? You smile, and possibly 

 think that Homer s Iliad is good as a means of culture. 

 There s the rub. The people who demand of science prac 

 tical uses, forget, or do not know, that it also is great as a 

 means of culture ; that the knowledge of this wonderful 

 universe is a thing profitable in itself, and requiring no 

 practical application to justify its pursuit. But while the 

 student of Nature distinctly refuses to have his labors 

 judged by their practical issues, unless the term practical 

 be made to include mental as well as material good, he 

 knows full well that the greatest practical triumphs have 

 been episodes in the search after pure natural truth. The 

 electric telegraph is the standing wonder of this age, and 

 the men whose scientific knowledge and mechanical skill 

 have made the telegraph what it is are deserving of all 

 honor. In fact, they have their reward, both in reputation 

 and in those more substantial benefits which the direct ser 

 vice of the public always carries in its train. But who, I 



