336 PHYSIOLOGY AND HEALTH. 



770. This arrangement of the brain and nerves and their 

 terminations, or points of impression, with their relation to 

 each other, is similar to that of the bells in a hotel and the 

 servant who watches them. The wires extend from the 

 several rooms to the corresponding bells in the central room, 

 or the servants' hall. Whenever the occupant of any room, as 

 No. 66, wants any thing, he pulls his wire, and the bell No. 

 66 rings. The servant, seeing this, immediately recognizes 

 a want in No. 66, and refers this to no other room. His 

 only conception is that of the connection of bell No. 66 with 

 room No. 66. Now, if any one should hit the wire between 

 these two points, and ring the bell, the servant would have the 

 same conception of a want in No. 66. Possibly this room 

 might be cut off, and the wire and bell remain; if then the 

 wire is drawn and the bell rings, the conception is still the 

 same of a want in No. 66. So the brain, when it receives 

 any impression at the inner end of the nerve of the finger 

 or the eye, has no other sensation than of something pleasant 

 or painful in the finger, or of light in the eye ; and even 

 though the finger or the eye be lost, if the nerve remains and 

 is irritated, the brain still has the same sensation. 



CHAPTER IV. 



Pains in amputated Limb. Motion excited by touching Motory 

 Nerves. Rapidity of Nervous Action. Voluntary and Involun- 

 tary Organs. Involuntary Motions fatigue less than Voluntary. 



771. THE last section will explain some singular facts in 

 regard to amputated limbs. Even after the nerves are di- 

 vided, or cut off, the remaining parts, if irritated, may excite 

 in the brain the same sensations as if they were entire. 

 Sometimes men, after a leg has been amputated, complain 

 of suffering great pain in the feet and the toes of the sepa- 

 rated and buried limb ; and some, believing there was a 

 mysterious connection between the body and the lost limb, 

 have caused it to be taken up and examined, to see if there 



