94 



THE ANIMAL AS A MACHINE. 



associated with the radiation of flame of the luminous 

 quality of those familiar to all of us. Thus " nature 

 produces this cheapest light at about one four-hundredth 

 part of the cost of the energy which is expended in the 

 candle-flame and at but an insignificant fraction of the 

 electric light or the most economic light which has yet 

 been devised." Many deep-sea fishes and nnmberless 

 animalcules exhibit a solution of this problem. 



31. The Advantage to be hoped for from the sub- 

 stitution of the economical ways of nature for the 

 wasteful ways of man may be imagined from the fol- 

 lowing facts : Experiments by Mr. Merritt, in the Cor- 

 nell University laboratories, have shown the wastes of 

 the incandescent electric lamp to be from 93I- to 99I- 

 per cent, according to intensity of current ; while Mr. 

 Nakano's tests, in the same place, of the arc lamp give 

 a waste of 95 to 84 per cent. The insect wastes almost 

 nothing. But even now the electric light has ten or 

 fifteen times the efficiency of the oil-lamp, and is still 

 better as compared with the candle. Professor Lang- 

 ley found the common gas-burner to waste 99 per cent 

 of the developed energy of combustion. His fireflies 

 were more efficient in the proportion of one to thousands. 

 The six millions of tons of coal supposed to be con- 

 cealed in the earth, at our present rate of consumption, 

 if employed for power-production, would supply about 

 fifteen thousand millions of horse-power for twelve 

 thousand years ; but could we discover and employ 

 nature's methods and gain in such proportion as is 

 indicated above, we might feel sure that all the wants 

 of the race would be supplied as long as the earth 

 should continue the possible abode of man. Years 

 ago it was remarked in an inaugural address as presi- 



