TOBACCO. 221 



9. Tobacco is often indulged in for the sake of soothing 

 the nervous system or lessening the feeling of mental 

 fatigue or worry. It also decreases the oxidations of the 

 body, and its wasting, and so enables it to get along 

 with less food; it may in this way be useful to a starv- 

 ing or ill-fed person. It contains a small amount of an 

 active principle, nicotin^ which is a powerful poison. A 

 few drops of pure nicotin will cause rapid death by para- 

 lyzing the heart. When tobacco is smoked, some of the 

 nicotin is burned; but vapors containing ammonia are 

 formed, and these irritate the mouth and throat. The 

 ill effects of smoking are thus,' in part, general due to 

 absorbed nicotin; and in part local due to irritating 

 matters in the smoke. It cannot be denied that many 

 persons consume a good deal of tobacco without being 

 much harmed by it. But it does no one any good unless 

 he cannot get sufficient food, or his nervous system is so 

 diseased or irritable that it needs soothing. One gen- 

 eral rule may be laid down without fear of contradiction: 

 tobacco is always very injurious to those whose bodies are not 

 yet fully developed. 



10. The Local Action of Tobacco is at first manifested by 

 an increased flow of saliva. After some practice in 

 smoking this effect ceases, and is succeeded by a feel- 

 ing of dryness in the mouth, which often leads to indul- 

 gence in alcoholic drinks. In this perhaps lies the 

 greatest danger from tobacco. The habitual smoker 

 often suffers from what is well known to physicians as 



9. Why is tobacco indulged in ? When may its use be beneficial ? 

 What is said of nicotin ? What becomes of it when tobacco is smoked ? 

 The ill effects of smoking ? What general rule may be safely stated ? 



10. How does the local action of tobacco first show itself? How 

 is this changed by practice in smoking? Point out one of the chief 



