1012] Elertricity Supply : Past, Present and Future. 431 



WEEKLY EVENING MEETING, 

 Friday, April 19, 1912, 



The Right Hon. The Duke of Northumberland, K.G. P.O. 

 D.C.L. LL.D. F.R.S., President, in the Chair. 



Alan A. Campbell Swinton, Esq., M.Tnst.C.E. M.I.E.E. M.R.I. 



Electricity Supply : Past, Present and Future. 



It was about the year 600 B.C. that Thales of Miletus discovered 

 that when amber was rubbed with silk it acquired the property of 

 attracting light bodies owing to its electrification, and hence it is 

 from the word electron, which is Greek for amber, that the term 

 electricity has been derived. The Greeks and Romans, however, made 

 no use of electricity. 



During the seventeenth and eighteenth centuries of our era much 

 scientific work was done in elucidating electrical phenomena until, 

 in the year 1799, Alexander Volta announced the construction of his 

 first pile, which was to lay the foundations for those scientific appli- 

 cations which have led to electricity supply being the important 

 factor it has become in our modern civilization. For a long time 

 galvanic batteries based in principle on Yolta's pile were the most 

 efficient known generators of electric currents, and it was with a 

 battery of this description, consisting of 2000 plates arranged in 200 

 porcelain troughs, one of which actual troughs is on the lecture table 

 this evening, that Humphry Davy first obtained, in 1809, in this 

 very Royal Institution building, the electric arc light, which was 

 destined at a later date to play so important a part in bringing about 

 a demand for electricity supply as we now know it. After Davy, for 

 many years the chief application of electricity was in connection with 

 telegraphy, and here, until quite recently, galvanic batteries were 

 generally employed to afford the necessary supply, though magneto 

 generators, based on the discoveries of Faraday, to which allusion 

 will be made later, were also used in the telegraphic apparatus of 

 Wheatstone, Henley and others. 



So far as this country is concerned, it was not till 1853-1856 

 that we find really practical applications of the electric arc lamp, it 

 being then employed for the lighting of Dungeness and other liglit- 

 houses in conjunction with the Holmes magneto-electric machine. 

 It was on the occasion of a visit to one of these lighthouses that 



