REMARKABLE TELEGRAPHIC EXPERIMENT. 



no degree of familiarity can efface the sense of wonder which the 

 effects of this most marvellous application of science excites. 



9. Being at Paris some years ago, I was engaged to share with 

 M. Leverrier, the celebrated astronomer, and some other men of 

 science, in the superintendence of a series of experiments to he 

 made before committees of the Legislative Assembly and of the 

 Institute, with the view of testing the efficiency of certain tele- 

 graphic apparatus. On that occasion operating in a room at 

 the Ministry of the Interior appropriated to the telegraphs, into 

 which wires proceeding from various parts of France were brought, 

 we dictated a message, consisting of about forty words, addressed 

 to one of the clerks at the railway station at Valenciennes, a 

 distance of 168 miles from Paris. This message was transmitted in 

 two minutes and a half. An interval of about five minutes 

 elapsed, during which, as it afterwards appeared, the clerk to 

 whom the message was addressed was sent for. At the expiration 

 of this interval the telegraph began to express the answer, which, 

 consisting of about thirty-five words, was delivered and written 

 out by the agent at the desk, in our presence, in two minutes. 

 Thus, forty words were sent 168 miles and thirty-five words 

 returned from the same distance, in the short space of four 

 minutes and thirty seconds. 



But surprising as this was, we soon afterwards witnessed, in 

 the same room, a still more marvellous performance. 



The following experiment was prepared and performed at the 

 suggestion and under the direction of M. Leverrier and 

 myself : 



"Two wires, extending from the room in which we operated to 

 Lille, were united at the latter place, so as to form one continuous 

 wire, extending to Lille and back, making a total distance of 

 336 miles. This, however, not being deemed sufficient for 

 the purpose, several coils of wire wrapped with silk were 

 obtained, measuring in their total length 746 miles, and were 

 joined to the extremity of the wire returning from Lille, thus 

 making one continuous wire measuring 1082 miles. A message 

 consisting of 282 words was then transmitted from one end of the 

 wire. A pen attached to the other end immediately began to 

 write the message on a sheet of paper moved under it by a simple 

 mechanism, and the entire message was written in full in the 

 presence of the Committee, each word being spelled completely 

 and without abridgment, in fifty-two seconds, being at the average 

 rate of Jive icords and four-tenths per second! 



By this instrument, therefore, it is practicable to transmit 

 intelligence to a distance of upwards of 1000 miles, at the rate of 

 19500 words per hour ! 



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