1839.3 Telegraphic Signals by induced electricity. 731 



As no intermediate stations would be required, the expenses of esta- 

 blishment would be very trivial. 



The cost of a magneto-electric machine of the maximum power 

 would not exceed 20/. The galvanic apparatus, constructed on the 

 principle I described in 1837, would not at most cost 10/. and would 

 probably cost 51. per month for its constant support. 



In Europe or America there exists no difficulty whatever to the 

 adoption of this system of correspondence. In India unquestionably the 

 obstacles are greater. Perhaps, however, on the other hand the very 

 wildness of our jungle tracts would rather protect than endanger the 

 buried wire. If properly laid down, in a few months none but those 

 instructed, could find it. But wherever a railroad exists, there this 

 method can be at once adopted. Indeed its applicability is so certain and 

 infallible, its principles so simple, that I often wonder it has not been 

 previously employed or even announced, and that the justly celebrated 

 Mr. Wheatstone should have taken out a patent for a five-wired 

 telegraph when every railroad in England already gives the required 

 conductors. 



The progress of science is hourly adding to the catalogue of tri- 

 umphs effected by the sagacity of man over the seeming impossibili- 

 ties of nature. Our own day has witnessed the miracle of gas illumi- 

 nation — the discovery of precious metals in potashes and in common 

 salt — the extrication of the electric spark through the influence of mag- 

 netism — the solidification of carbonic acid — the fixing by the sun's light 

 of the pictures it forms whether by shadow, reflection, or refraction. 

 A conquest still greater than all which I have quoted would be the 

 annihilation of time and space in the accomplishment of correspond- 

 ence. That a signal can be passed between places 1,000 miles apart in 

 less time than the motion of solar light through the firmament, is no 

 less startling to assert than it is demonstrably and practically true. 



