.s7A- ////././. /.i/ .SYAM/A-.V.V, F.K.S. 209 



which Trinity House commanded, the minor difficulties to which 

 : in- had been made by Admiral Collinson would soon l)e 

 removed, and that they would have a light, not only of 16,000, 

 but perhaps of 20,000 or 30,000 candles, at a reasonable cost, and 

 with great advantage to the navigation of the country. 



ON THE TRANSMISSION AND DISTRIBUTION OF 

 ENERGY BY THE ELECTRIC CURRENT. 



BY C. WILLIAM SIEMENS,* D.C.L., F.R.S.t 



IN the autumn of 1870, when standing below the Falls of 

 Niagara, the first impression of wonderment at the imposing spec- 

 tacle before my eyes was followed by a desire to appreciate the 

 amount of force thus eternally spent without producing any other 

 result than to raise the temperature of the St. Lawrence a fraction 

 of a degree,}: by the concussion of the water against the rocks 

 upon which it falls. 



The rapids below the fall present a favourable opportunity of 

 gauging the sectional area and the velocity of the river ; and from 

 these data I calculated that the fall represents energy equivalent 

 to nearly 17 million horse-power, to produce which by steam would 

 require about 26<> million tons of coal a year, or just about the 

 entire amount of coal raised throughout the world. 



If one fall represents such a loss of power, what must be the 

 aggregate loss throughout the world from similar causes ? and is 

 it consistent with utilitarian principles that such stores of energy 

 should go almost entirely to waste ? But the difficulty arises, how 

 such energy (occurring as it does for the most part in mountainous 

 countries) is to be conducted to centres of industry and population. 



Transmission by hydraulic arrangements or by compressed air 

 would be very costly and wasteful for great distances ; but it 



* Excerpt Philosophical Magazine, Vol. VII. 1879, pp. 352-356. 

 t Read at the Meeting of the Physical Society on February 22, 1879. 

 The vertical fall being 150 feet, the increase of temperature would be 

 }?-{ = $ Fabr. nearly. 



VOL. II. P 



