RECOIL CURRENTS. 



remunerative return, icill it pay ? Or, on the other hand, may it 

 not be regarded as one of those vast international enterprises to 

 which the influence and resources of states should be applied? 

 These are questions which we have neither the space nor the 

 vocation to discuss. 



95. In 1852, the conducting wires which connect the Branch 

 Telegraph Office, established in the Strand, opposite Hungerfoid 

 Market, with the General Post-office, were laid down. In this 

 case the conducting wires are galvanised brass instead of copper. 

 They are as usual laid in iron tubes, and are carried along the 

 kerb stones of the foot pavement of the Strand, Fleet-street, 

 Ludgate-hill, and St. Paul's Church-yard to Cheapside, where 

 they cross over to Foster-lane, and passing through the branch 

 office in the hall of the General Post-office, are carried thence 

 to the central telegraph station in Lothbury, at the rear of the 

 Bank of England. 



From this central office, at all hours by day and by night, 

 despatches are transmitted to and received from every seaport and 

 every considerable town in England, Scotland, and Wales ; by the 

 submarine wires, by Holyhead and Portpatrick, from all parts 

 of Ireland, and by Dover, from all parts of the Continent of 

 Europe where electric telegraphs have been constructed. 



96. After the underground and submarine wires had been con- 

 structed and laid upon a considerable scale, the attention of Dr. 

 Faraday was called by some of the parties engaged in their 

 management to peculiar phenomena which had been manifested 

 in the telegraphic operations made upon the lines thus laid. After 

 experiments had been made upon a large scale with lines of sub- 

 aqueous and subterranean wires, extending to distances varying 

 from 100 to 1500 miles, it was found that the electricity supplied 

 by the voltaic battery to the covered wire was in great quantity 

 arrested there, by the attraction of electricity of an opposite kind 

 evolved from the water or earth in which the wire is sunk ; the 

 attraction acting through the gutta percha covering exactly in the 

 same manner as that in which the electricity developed by a 

 common electric machine, and deposited on the inside metallic 

 coating of an electric jar, acts through the glass upon the natural 

 electricity of the external coating, or of the earth in connection 

 with it. The two opposite electricities on the inside and outside 

 of the coating of the wire by their mutual action neutralise each 

 other, and under certain circumstances a person placing his hands 

 in metallic connection with both sides of such coating, may ascertain 

 the presence of a large charge of such neutralised fluid, by receiving 

 the shock which it will give like that of a charged Leyden jar. 



97. It is apprehended that this unforeseen phenomenon may 



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