120 ELEMENTARY PHYSIOLOGY. 



drops of this poison, placed on the tongue of a dog, 

 will cause death. This nicotine, extracted from the 

 tobacco and evaporated, forms large parts of the 

 crust in the bowl of an old tobacco pipe. 



Its use is unnatural. When first at- 

 <mthe ireCt8 tempted, it causes nausea and nervous 

 Young:. and muscular weakness. It is a well- 



known fact that it exerts a very perni- 

 cious influence, particularly upon the young. It 

 prevents their physical and mental development; it 

 stunts their growth, and paves the way for disease 

 in after years. 



Injurious as tobacco smoking (in its 

 common form) may be, smoking cigar- 

 ettes is even more so. The poorest 

 kind of tobacco is often used in making them, and 

 poisonous substances are added to give them the 

 proper strength and flavor. Opium, which is used 

 in considerable quantities in this adulteration, is 

 carried with the smoke to the lungs. Nicotine, that 

 deadly poison found in tobacco, aids in the poison- 

 ing process. In view of the detrimental effect of 

 cigarettes, it is not surprising that a number of 

 States have enacted laws prohibiting the sale of 

 cigarettes to young boys. 



To show you that 'the mucous lining of 

 ment. X1 *^ e mouth and air passages is sub- 



jected to a sort of tanning process, and 

 thus has its ordinary functions impaired by cigar- 

 ette smoking, a simple experiment may be per- 



