Inaugural Address by the President. 



29 



T^ 6 



r/j The current in passing 



^ j I round the coil attracts 



^^^**»T,ii5-(t=jr^s^^ upwards the core E 



and its attachments, 

 including the knife F^ 

 with a force of 3 to 4 

 lbs. In order to let it 

 fall again it is only 

 necessary to break the 

 current, which is done 

 by the sliding break or 

 collar G. The current 

 in entering the coil D 

 passes through the two 

 contact springs J J and 

 the sliding collar G, 

 making connexion bet- 

 ween them, but as soon 

 as the core in rising has 

 stretched out the spring 

 supports H H of the 

 collar far enough to 

 draw it up out of con- 

 tact, the circuit is 

 broken and the core 

 falls by its own weight 

 assisted by the re- 

 silience of a buffer 

 spring E^ under the 

 coil. The sliding collar 

 break follows it down 

 and again completes 

 the circuit, and so the reciprocating action continues. The 

 material to be chopped is placed in a vessel with a wooden 

 bottom as indicated in the figure by broken lines. 



Besides this vertical motion it is necessary to rotate the 



