APPLICATION OF THE ELECTBIC TELEGBAPH. 309 



second, in coincidence with the beats of his mean solar 

 chronometer, and continues to do so for ten or fifteen 

 minutes without interruption. The party at the second 

 station compares the armature click of his magnet with 

 the beats of his sidereal clock, and watches for a coinci- 

 dence, and records the time when a coincidence takes 

 place. When he has obtained two or three coincidences, 

 which generally requires from ten to fifteen minutes, he 

 breaks the electric circuit, in order to notify the first 

 party to stop beating. He then commences beating 

 seconds by striking his own signal key in coincidence 

 with the beats of his sidereal clock ; and the party at the 

 first station compares the armature clicks of his magnet 

 with the beats of his solar chronometer, and watches for a 

 coincidence. When he has obtained three or four coin- 

 cidences, which generally requires ten or twelve minutes, 

 he breaks the electric circuit, in order to notify the 

 other party to stop beating. The comparison of times at 

 the two stations is now complete. 



The following is the result of this summer's campaign : 



DIFFERENCE OF LONGITUDE BETWEEN 



Means. 7m. 333.079 4m. 308.397 12m. 3s. 504 



