APPLICATIONS OF THE ELECTRIC LIGHT. 251 



/. K, p. 550. But these systems, which were founded either 

 on derivations of the current, or on rapid successive permu- 

 tations of the current through a certain number of different 

 circuits, or on the revolving projection of a beam of light, were 

 destitute of arrangements sufficiently energetic and well con- 

 trived to solve the problem. It was not until Lontin, 

 Lodyguine, and Jablochkoff had made their earlier experi- 

 ments that the possibility of dividing the electric light began 

 to gain some degree of credence. There was still, however, 

 great doubt as to the possibility of illuminating a space of con- 

 siderable length. It was supposed the loss of electric intensity 

 from the length of the conductors could absorb all the power 

 of the generator, and that sufficient electric energy would not 

 be left to light several lamps. But Jablochkoff's experi- 

 ments, performed on the whole length of the Avenue de 

 rOp'era, with only one machrne for each side of the street, 

 completely removed all doubts on this head, and from that 

 time, as we have already said, the problem of electric light- 

 ing has come to the front in every country. We must there- 

 fore devote a few lines to these remarkable experiments, 

 which are still carried on at the present moment, and are 

 being extended to other important thoroughfares in Paris. 



In the Avenue de r Opera and the Place du Theatre- Fran$ai$ 

 there are 32 lamp-posts carrying the electric light, 16 on each 

 side. The lamp-posts are the ordinary ones of the city of 

 Paris, supported by circular oaken pedestals i '5 metres high, 

 and surmounted by lamps like that shown in Fig. 65, page 

 225. Each lamp holds six candles, and seven wires enter it 

 from the interior of the lamp-post after having passed through 

 a commutator of six contacts placed within the pedestal. The 

 machines which work these different lamps are set up in two 

 cellars under the middle of the street, and therefore the wires 

 are divided into two bundles for each machine ; two of these 

 bundles go up the street on each side, and the other two 

 down. The wires are buried in the earth below the pave- 

 ments, and besides their insulating covering of gutta-percha. 



