THE LOCAL ACTION OF TOBACCO. 363 



capillary vessels, causing purplish patches on the skin. 

 Jaundice also frequently occurs. 



If the chloral-biking be still continued, death results 

 from impoverished blood, weakened hearc, or paralysis of 

 the nervous system. Not unfrequently chloral-takers un- 

 intentionally commit suicide by indulging in too large a 

 dose. 



Tobacco contains an active principle, nicotin, which 

 in its pure form is a powerful poison, paralyzing the 

 heart. When tobacco is smoked some of the nicotin is 

 burned, but there are developed certain acrid vapors which 

 have an irritant action on the mouth and throat. The 

 effects of smoking are thus in part general, due to absorbed 

 nicotin; and in part local, due to irritant matters in the 

 smoke. They vary much with the constitution, habits, 

 and age of the smoker. One general rule at least may be 

 laid down: tobacco is very injurious to young persons whose 

 physical development is not completed. 



The Local Action of Tobacco is at first manifested by in- 

 creased flow of saliva. This usually passes off after some 

 practice in smoking; dry ness of the mouth follows, and con- 

 sequent thirst, often leading to alcoholic indulgence; and 

 in this, perhaps, lies the greatest danger from tobacco. 

 The habitual smoker usually suffers eventually from what 

 is known to medical men as " smoker's sore-throat." The 

 inflammation often extends to the larynx, injuring the 

 voice and producing a hacking cough, or may spread up 



How does death from chloral occur? 



What is nicotin? What other injurious substances are found in 

 tobacco-smoke? What general rule may be stated concerning the 

 action of tobacco on the human body? 



Describe the local actions of tobacco. How may tobacco-smoking 

 injure the voice? How the hearing? 



