BAIN'S CHEMICAL TELEGRAPH. 



the characters have been correctly marked on the perforated 

 paper ; but this correctness is secured by the ribbon of perforated 

 paper being examined after the perforation is completed and 

 deliberately compared with the written message. Absolute 

 accuracy and unlimited celerity are thus attained at the station 

 of departure. To the celerity with which the dispatch can } be 

 written at the station of arrival there is no other limit than the 

 time which is necessary for the electric current to produce the 

 decomposition of the chemical solution with which the prepared 

 paper is saturated. 



215. It may be asked then why this form of telegraph, affording 

 as it does the means of obtaining a celerity of transmission so 

 far exceeding any other that has been projected, has not been 

 universally adopted ? 



To this it may be answered that the celerity here described can 

 only be attained after the dispatch to be transmitted has been 

 marked in the pierced telegraphic characters on the ribbon of 

 paper, and that the process of so marking it would not be more 

 rapid, however expert the operator might be, than that by which 

 the same operator would transmit the same dispatch directly by 

 the key commutator, either with this telegraph or those described 

 in (191, 192). If, therefore, the time necessary to commit the 

 dispatch in telegraphic characters to the perforated ribbon of 

 paper, be included in the estimate of the time of its transmission 

 from station to station, this form of telegraph is not only slower 

 and consequently less efficient than either of those described in 

 (191, 19,2), but it is slower than any other form of telegraph 

 whatever. 



It must therefore be admitted, that, so long as the demands upon 

 the conducting wires do not exceed their powers of transmission 

 by the operation of the ordinary methods now commonly practised, 

 the contrivance of Mr. Bain can present no very strong claims for 

 preference over the other systems. But if the demands of the 

 public should be greatly multiplied, as they certainly would be 

 by lowering the tariff, then the method above described would be 

 presented under different conditions, and might become the only 

 expedient of all those hitherto contrived, by which such augmented 

 demands could be satisfied. 



216. If for example the time should arrive when a much more 

 considerable share of the demands now satisfied by the post-office 

 should be transferred to the telegraph; if instead of short and 

 unsatisfactory dispatches conveying political and general intel- 

 ligence to the journals, fully detailed circumstantial statements 

 and reports were required ; if the same full reports of speeches 

 and debates, on occasions of great public interest, or reports of any 



53 



