Chemical and Physical Papers. 47 



THE DEVELOPMENT OF MECHANICAL POWER IN THE 



LAST DECADE. 



F. H. SiHi.KY, Ijinvii'iice. 



EVEN as we are accustomed to think of history as divided 

 into epochs, having more or less well-defined limits, so 

 the future historian will undoubtedly define the present era 

 probably as the age of the industrial revolution. One of the 

 chief agencies, probably the principal agency, in this revolution 

 is the production of mechanical power. 



Few realize, as they go about their daily affairs, how in- 

 dispensable is this commonplace thing to modern life. Sub- 

 tract all of its results and see what we have left : rapid tran- 

 sit by stage coach, every convenience depending upon the ap- 

 plication of electricity eliminated ; home-spun clothes, little 

 variety of food, little or no ice; little communication between 

 distant individuals, few books and no newspapers. In short, 

 subtract everything that is wholly or in part dependent upon 

 power, and how much of the progress of the last thousand 

 years would be apparent? 



While we have gone far and fast in the production of power 

 to meet the continually increasing demands of an industrial 

 age, when we consider the lavish supply of materials for its 

 production with which the earth is stored, and the fact that 

 most of it is wasted through ignorance and inefficient methods, 

 we must humbly admit that the art of producing mechanical 

 power is still in its infancy. 



In the most successful attempt that man has made to utilize 

 the forces of nature for this purpose, the development of 

 the water fall, he is able to realize only about 33 per cent 

 of the actual power of the water in useful work per- 

 formed. In plants which derive their power from stored heat 

 energy the showing is much less favorable, the work of the 

 street car in ton miles or the candlepower of the electric 

 lamp being commonly less than two per cent of the equivalent 

 heat energy stored in the coal. 



Percentages make little impression on the mind unac- 

 customed to dealing with these matters. Let us put the state- 

 ment in a little more startling way. In 1908, an average year, 



