NERVES AS MESSAGE CARRIERS. 



been produced if the fibre were still continued 

 to its original destination and were stimulated 

 there, and they would arouse in the brain 

 much the same sensation as before. So that 

 if the fibres stimulated were those which for- 

 merly ran to the toes of the right foot, the 

 patient may feel a pain or tingling in those 

 members, even after the right leg has been 

 amputated. 



3. Immediate Action Impossible. 



We have often been told to do such and 

 such things immediately. To these orders 

 obedience in the most strictly literal sense is 

 impossible. 



First of all, the command, when received, 

 has to be conveyed by nerves from the ear 

 or eye to the central administration office, 

 the brain. The brain, after doing a certain 

 amount of office work in recording the receipt 

 of the message, and its relation to other events 

 preceding or contemporaneous, sends out an 

 order to the hand or foot which has to perform 

 the evolution necessary to the accomplish- 

 ment of the command, and this last order has 

 to travel along the nerves to its destination. 

 Now, the nerves, in carrying messages, behave 

 in much the same way as the wires of the elec- 

 tric telegraph, to which they have been very 

 frequently compared. 



263 



