MORSE'S TELEGRAPH. 



This telegraphic apparatus being that which has been by far 

 the most extensively brought into use, being not only adopted 

 almost exclusively in the United States and contiguous countries, 

 but also in all the German States, it may' be useful here to present 

 the instrument and its appendages in the form in which it has been 

 most recently constructed in the United States, and which has 

 been recommended by the American telegraphic confederation, as 

 being that which it would be most advantageous to adopt gene- 

 rally, so that all the parts being manufactured of the same pattern 

 and size no difficulty would be found in replacing any of them in 

 case of fracture. 



A perspective view of the instrument, omitting the paper roller 

 and ribbon, is given in fig. 83 (p. 44). 



z. The wooden base upon which the instrument is screwed, 



B. The brass base plate attached to the wooden base z. 



A. The side frames supporting the mechanism. 



A, h. Screws which secure the transverse bars connecting the 

 side frames. 



G. The key for winding up the drum containing the main- 

 spring, or supporting the weight, according as the mechanism 

 is impelled by one or the other power. 



3, 4. Clock-work. 



w, A lock or gauge to regulate the pressure of the rollers on the 

 paper. 



c. The pillar supporting the electro-ma|net. 



p. The adjusting screw passing into the pillar, c, projecting 

 through the armature, to enable the telegraphist to adjust the 

 sound of the back stroke of the armature at pleasure. 



0. The spring bar, and 



d, the screw to adjust the action of the pen lever. 

 D. The apparatus for adjusting the paper rollers. 

 /. The adjusting screw of the pen lever. 



The form of the relay magnet recommended, is given in fig. 

 84 (p. 45), in its proper size. 

 A B, are the helices or coils, 

 c. The supporter of the magnet lightly screwed to 

 w, the connecting bar of the magnets. 

 Y. Rosewood or ivory ends of magnets. 



D, Armature screwed to 



E, an upright lever ; 



F, its axis, surrounded by a spiral spring, to perfect the con- 

 nection in case of a fault at the ends of the axle. 



M. The spring to produce the recoil of D and E. 



1. Its adjusting screw. 



3. An adjusting screw to limit the play of E towards the magnet; 



43 



