THE NERVOUS SYSTEM. 151 



SECTION IV. 1, We say that a person is nervous when 

 his nervous system is excited by trifling matters. Sick- 

 ness makes people nervous. Close rooms and bad air make 

 people nervous. Lack of exercise makes people nervous. 

 Indigestible food makes people nervous. The nervous 

 system will endure a great deal of wear if rightly treated. 

 Lack of sleep, too much excitement, and anxiety, often 

 break it down. Worry is much more wearing than 

 work. Stimulants, which spur the nerves continually, 

 finally prostrate them. 



2, Actions at first done with care and thought, by being 

 done frequently, are at length done without effort. They 

 become partly reflex acts. That is the reason why a 

 skilled workman can work so much longer without being 

 tired than a stronger man could, who was not so skill- 

 ful. In this way good habits help us, good habits of 

 position, of movement, of speech, of study. So bad habits 

 make slaves of us. The habit of biting the nails is, in 

 many persons, a reflex act, which it is difficult to refrain 

 from, because it is done without thought. 



3. The brain needs exercise just as truly as the muscles. 

 Study and thought not only make the brain strong and 

 clear: they help to keep it in good health. 



EFFECTS OF ALCOHOL ON THE NERVOUS SYSTEM. 



SECTION V. 1. Alcoholic drinks are used chiefly for 

 their effects on the nerves and brain. They stimulate the 

 sense of taste in the tongue and palate, and they warm the 

 stomach. Without really increasing strength, they give a 

 feeling of strength and confidence. In moderate doses, 

 they excite the braiii. The sensibilities become lively, 

 ideas flow readily, wit seems brighter, and philosophy 



