Masterpieces of Science 



while the other end is heated to redness, yet one 

 millionth part of this same energy, if in the form 

 of electricity, would traverse the rod in one 

 ioo,ooo,oooth part of a second. Compare next 

 electricity with light, often the companion of 

 heat. Light travels in straight lines only; elec- 

 tricity can go round a corner every inch for 

 miles, and, none the worse, yield a brilliant 

 beam at the end of its journey. Indirectly, 

 therefore, electricity enables us to conduct either 

 heat or light as if both were flexible pencils of 

 rays, and subject to but the smallest tolls in 

 their travel. 



We have remarked upon such methods as 

 those of the electric welder which summon in- 

 tense heat without fire, and we have glanced at 

 the electric lamps which shine just because com- 

 bustion is impossible through their rigid ex- 

 clusion of air. Then for a moment we paused to 

 look at the plating baths which have developed 

 themselves into a commanding rivalry with the 

 blaze of the smelting furnace, with the flame which 

 from time immemorial has filled the ladle of the 

 founder and moulder. Thus methods that com- 

 menced in dismissing flame end boldly by dis- 

 possessing heat itself. But, it may be said, this 

 usurping electricity usually finds its source, after 

 all, in combustion under a steam-boiler. True, 

 but mark the harnessing of Niagara, of the 

 Lachine Rapids near Montreal, of a thousand 

 streams elsewhere. In the near future motive 

 power of Nature's giving is to be wasted less and 

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