HISTORY AND PROGRESS. 147 



armature attached to one end of a lever, at the other end of 

 which is a spiral spring for drawing back the armature when 

 the current ceases, the oscillation of the lever being limited 

 by anvils. When a current circulates round the cores the 

 magnetism induced attracts the armature, by which the end 

 of the lever strikes on the top of the lower anvil, and produces 

 a sharp noise ; on the cessation of the current, the armature is 

 let go, and the lever drawn back by the tension of the spring 

 strikes with a less intense noise on the upper anvil. Adjusting 

 screws attached to the spring enable the operator to regulate 

 the sounds of the beats on the two anvils. With this excep- 

 tion the whole arrangements of the Morse system, of relays, 

 keys, &c., remain the same. 



Prescott says : " It was soon discovered after the introduc- 

 tion of the Morse system of telegraphs that words could be 

 read by the click of the magnet ; but paper was used upon 

 which the arbitrary alphabet of dots and lines was indented 

 by the instrument for all matters of business up to 1852, and 

 by many lines even later ; but at the present time there is 

 scarcely an office of any importance in the United States 

 where the paper is used to receive the record." 



The same author says that since the abolition of the paper 

 upon the Morse lines errors rarely occur ; that the ear of 

 the employe is found to be a much more reliable organ than 

 the eye ; not one error being made in reading by sound, 

 while at least ten were made formerly in reading from the 

 paper. 



The system has, nevertheless, the disadvantage that it 

 leaves no record for the justification of the operator. In 

 France the messages are invariably recorded by the Digney 

 instrument, but it is not unfrequent that the employes read 

 the message by ear before looking at the paper. 



In addition to the methods already mentioned of recording 

 messages by the Morse on paper strips by the decomposition 

 of salts, by scoring or embossing, and by inking, it has 

 likewise been attempted to attain the same object by burning 

 holes in, and by scorching the paper. 



Home, for example, suggested the employment of a bent 



L 2 



