REFLECTIONS ON PRA TKR AND NA TURAL LA W. 345 



which our gem must be sought. A modified and more 

 refined form of the ancient faith revived; and, for aught I 

 know, a remnant of sanguine designers may at the present 

 moment be engaged on the problem which like-minded men 

 in former ages left unsolved. 



And why should a perpetual motion, even under modern 

 conditions, be impossible? The answer to this question is 

 the statement of that great generalization of modern 

 science, which is known under the name of the Conser- 

 vation of Energy. This principle asserts that no power 

 can make its appearance in nature without an equivalent 

 expenditure of some other power; that natural agents are 

 so related to each other as to be mutually convertible, but 

 that no new agency is created. Light runs into heat; 

 heat into electricity; electricity into magnetism; magnet- 

 ism into mechanical force; and mechanical force again into 

 light and heat. The Proteus changes, but he is ever the 

 same; and his changes in nature, supposing no miracle to 

 supervene, are the expression, not of spontaneity, but of 

 physical necessity. A perpetual motion, then, is deemed 

 impossible, because it demands the creation of energy, 

 whereas the principle of Conservation is no creation, but 

 infinite conversion. 



It is an old remark that the law which molds a tear 

 also rounds a planet. In the application of law in nature 

 the terms great and small are unknown. Thus the prin- 

 ciple referred to teaches us that the Italian wind, gliding 

 over the crest of the Matterhorn, is as firmly ruled as the 

 earth in its orbital revolution round the sun; and that the 

 fall of its vapor into clouds is exactly as much a matter of 

 necessity as the return of the seasons. The dispersion, 

 therefore, of the slightest mist by the special volition of 

 the Eternal, would be as much a miracle as the rolling of 

 the Rhone over the Grimsel precipices, down the valley 

 of Hasli to Meyringeu and Brientz. 



It seems to me quite beyond the present power of science 

 to demonstrate that the Tyrolese priest, or his colleague 

 of the Rhone valley, asked for an " impossibility " in pray- 

 ing for good weather; but Science can demonstrate the 

 incompleteness of the knowledge of nature which limited 

 their prayers to this narrow ground; and she may lessen the 

 number of instances in which we "ask amiss," by showing 

 that we sometimes pray for the performance of a miracle 



