PRESIDENTIAL VDDRESS — SECTION A. 19 



Scotlatul is estimated to possess over 1.000,000 H.P. of water 

 power, and it has been pointed out that if the figure is halved it 

 would still represent, on a 10-honr working day basis throughout 

 the year, an amount of power equal to that obtained from 

 3A million tons of coal. Of course, considerable expense would 

 have to be incurred before this power could be utilized, but the 

 Kinlochleven installation, which provides for an output of 

 30,000 H.P.. has cost about £20 per H.P., which is a low capital 

 cost. Electric power derived from water has been publicly 

 advertised for sale as low as 30s. per H.P. per annum. 



In this country there is comparatively little water power 

 available, but it is surely astonishing that a portion, at least, of 

 the 300.000 to 600.000 H.P. of Victoria Falls has not yet been 

 utilized. Even the electric light for Victoria Falls Hotel is still 

 being furnished by an antiquated steam plant. 



For agricultural purposes, more especially irrigation, one 

 would expect that a very considerable amount of power could be 

 utilized within a radius of 300 miles of the Falls, and doubtless 

 developments in this direction will take place. 



In the matter of the transmission of power electrically, one 

 may mention that less than a year ago there were only some half 

 dozen systems in operation where a pressure as high as 100,000 

 volts was employed, but an undertaking has lately been com- 

 pleted near Lake Huron employing a pressure of 140,000 volts, 

 and the line has been in successful service since March last. 

 The limits of practical voltage have been given by various 

 engineers who think they know what may be ultimately feasible ; 

 some put the practical working limit of the future as low as 

 200,000 volts between conductors, but there are others who firmly 

 believe 300.000 volts will be used ; while, if the limit can be 

 pressed up to 500,000 volts it will be possible to couple most of 

 the power stations in the United States of America together, and 

 so be able to even up the load between them. 



Improvements in the methods of producing aluminium, 

 coupled with the reduced cost of electrical energy used, has had 

 the desirable effect of reducing the price of this metal to a figure 

 approaching that of copper, and this means that at present an 

 aluminium aerial line of large capacity is considerably cheaper 

 than a copper one. Xear the sea coast, however, aluminium is 

 attacked by the salt-laden atmosphere, since the metal has a great 

 affinity for chlorine, and it is rather doubtful whether it can be 

 profitably used in such districts. In Canada. United States of 

 America and Scandinavia, aluminium has been very extensively 

 used for electrical aerial transmission lines, and there are also 

 quite a number of small aluminium lines in use in England and 

 Scotland. 



The diagram, which has been plotted from a table of efficien- 

 cies in long-distance transmission given by Beringer, shows in a 

 striking manner the unique position occupied by electricity in the 

 transformation and transmission of energy. 



