NERVOUS SYSTEM DIAGRAM 2. 



19 



Nervous system of Man, 



closing the hand. Mad- 

 men, who are deran- 

 ged, or who no longer 

 know what they do, 

 are persons whose 

 brain is diseased. 

 When we say that 

 wine and brandy go 

 to the head we are 

 right, for they cause 

 disease of the brain 

 for some time, and 

 this disease produces 

 drunkenness. When 

 we place our hand 

 upon a hot or hard 

 body, the sensation of 

 heat or hardness is 

 transmitted to the 

 brain by the nerves of 

 the skin. If we want 

 to extend the arm, or 

 close the hand, the 

 nerves transmit the 

 wish to the muscles of 

 the hand and arm, 

 to make the move- 

 ment which the brain 

 desires. The brain 

 may be compared to 

 a central telegraph 

 office, connected with 

 all parts of the body 

 by wires, which][are 



c 2 



