HYGIENE OF THE NERVOUS SYSTEM 315 



than to excessive demands upon the nervous organism. 

 No part of the system is so carefully protected from 

 injury, so hedged about and guarded from evil influences 

 of every sort, as are the precious nerve centers. The nerv- 

 ous mechanism is the last to waste when the body dies 

 from starvation, and under such conditions it is probably 

 supported at the expense of other tissues as being more 

 important than they. 



Recalling what we have learned from previous study we 

 shall see clearly the importance and the source of nour- 

 ishment for the nerve cells. It is by the blood alone that 

 they are fed. Every thriil of nervous influence destroys 

 tissue, and unless an abundance of pure arterial blood is 

 at hand for rebuilding the cells, weakness and decay will 

 follow. Diseases which lead to blood poisoning as 

 pneumonia and typhoid fever are accompanied with 

 delirium, weakening of the mental faculties, or other nerv- 

 ous symptoms. 



460. In order that pure blood may be furnished, the 

 regular and perfect action of the digestive organs is in- 

 dispensable. Digestion is a slow process ; it cannot be 

 hastened. If we eat our food so rapidly that it is not 

 subjected to the action of the saliva, and is not properly 

 divided by the teeth, the gastric juice will not be able to 

 effect the necessary changes in the stomach, especially if 

 we hasten to call the blood away for other work too soon, 

 and the food will pass on into the intestines only half 

 ready for the work of the other juices. Even in a healthy 

 man the normal processes in the alimentary canal develop 

 an amount of poison sufficient to kill him if it is not neu- 

 tralized by the products of the liver, pancreas, and other 

 organs, which nature provides for that purpose. So, if 

 those secretions are interfered with, as they are by the 



