THE ELECTRIC TELEGRAPH. 



desires to transmit, and by continuing to operate thus, he transmits 

 the entire despatch. 



Such is the Belgian railway telegraph, and although it must he 

 admitted that it supplies a certain improvement on the French 

 telegraph, it ought also to he stated that the difficulty and incon- 

 venience which M. Lippens claims to have removed, has not heen 

 found to offer any practical obstruction to the satisfactory per- 

 formance of the French instruments. 



It appears that M. Lippens has lately made considerable im- 

 provements in the practical details of his telegraph, by which its 

 operation is rendered much more convenient. He has also sub- 

 stituted the magneto-electric for the voltaic current, and thus 

 dispensed with the voltaic battery. This last improvement has 

 not yet (July, 1854) been applied on the telegraphic lines, but 

 will be in operation, probably, before these pages come into the 

 hands of the reader. 



FEOMEXT'S ALPHABET TELEGUAPH. 



205. The external appearance of this instrument, represented 

 in fig. 81 (p. 33), is that of a small piano-forte, having, however, 

 no black keys. On each of the keys a letter of the alphabet is 

 engraved, the first key being marked with a cross, and the last 

 with an arrow. On the first ten keys are also engraved the 

 numerals. This part of the apparatus is the commutator, by 

 which the agent at the station where it is placed, is enabled to 

 transmit signals to any distant station. 



Upon it is placed the indicating apparatus, which is acted upon 

 by the commutator of the apparatus at a distant station, and by 

 which a despatch is received. This indicator is similar in form 

 and in the manner of giving its signals to that of the French 

 railway telegraph already described. The dial of the indicator is 

 marked with the letters of the alphabet, and the cross and arrow 

 corresponding with the characters engraved upon the keys of the 

 commutators. 



At the back of the case containing the indicating apparatus 

 the alarum is attached, and commutators are placed upon the 

 case by which this alarum can be put in connection at pleasure 

 with the line-wire. As usual it is always kept in connection with 

 it when the instrument is not in use, so that notice may be given 

 of the approaching arrival of a despatch. On the ringing of the 

 alarum the agent at the station turns off the commutator from 

 the alarum and throws it into connection with the indicating 

 apparatus. 



To explain the tranmission of a despatch, let us suppose an 

 apparatus, such as that represented in the figure, to be erected 

 38 



