732 POPULAR SCIENCE MONTHLY. 



required becomes as great as can be insulated with certainty in the 

 present state of the art, the distance of transmission is increased to 

 the utmost limits attainable in practice. Until some more per- 

 fect means for confining the current is devised, greater results can 

 not be reached. With our present knowledge of insulating ma- 

 terials, and our methods of applying them, it would be practically 

 impossible to transmit energy over distances as great as from New 

 York to Niagara, but it does not follow that the accomplishment of 

 this result will never be witnessed; it is a possibility of the future, 

 that may not come for a century or more, or may be realized within 

 the next few years. 



Although the achievement of such stupendous results as the 

 transmission of power over several hundred miles is not within our 

 present reach, it is possible to bridge distances of twenty or thirty 

 miles, and the accomplishment of this much has been considered 

 entirely practicable for several years. It was on this account that 

 the Niagara power plant was started, the object being to supply the 

 city of Buffalo and other places within a radius of twenty-five or 

 thirty miles. This undertaking, owing to the magnitude of the 

 power available, has attracted world-wide attention, and is probably 

 regarded by the vast majority of people as the only work of any 

 importance in this line that has been attempted. This, however, 

 is far from being true ; it is the largest, and will undoubtedly always 

 remain such, since the source of energy is practically unlimited, but 

 there are several other very large installations, and in some of these 

 the distance of transmission from a mile or so up to thirty-five miles, 

 place being nearly double that distance. 



A fair idea of the extent to which this branch of the electrical in- 

 dustry has been developed may be gained from a consideration of the 

 fact that one manufacturing concern alone has sold over two hun- 

 dred thousand horse power of machinery for this purpose within 

 the last four or five years, their sales for 1896 being over seventy- 

 five thousand horse power. The great increase in the business dur- 

 ing the past year, in the face of a general stagnation in all other 

 lines of industry, is a very clear indication that what has been done 

 in the past has been entirely successful so much so as to inspire an 

 amount of confidence sufficient to overcome the apathy or unwilling- 

 ness to embark in new undertakings so manifest in all other lines of 

 business. 



The total number of water-power transmission plants in success- 

 ful operation in the United States in addition to the Niagara installa- 

 tion is over two hundred. The amount of power transmitted ranges 

 from less than one hundred horse power up to twelve thousand, and 

 the distance of transmission from a mile or so up to thirty-five miles. 



