332 COORDINATION AND SENSATION 



of literature should be cultivated. Simple fairy tales which 

 have a recognized value in developing the imagination of 

 the child need not be omitted, but it is of vital importance 

 that the " story -reading habit " be not formed. 



Effects of Drugs. Because of its delicacy of structure a 

 number of chemical compounds, or drugs, are able to pro- 

 duce injurious effects upon the nervous system. Some of 

 these are violent poisons, while others, in small quantities, 

 are mild in their action. Certain drugs, in addition to their 

 immediate effects, bring about changes in the nervous 

 system which cause an unnatural appetite, or craving, that 

 leads to their continued use. This is the case with alcohol, 

 the intoxicating substance in the usual saloon drinks, and 

 with nicotine, the stimulating drug in tobacco. The same 

 is also true of morphine, chloral, and several other drugs 

 used as medicines. The danger of becoming a slave to 

 some useless and pernicious habit should dissuade one from 

 the use of drugs except in cases of positive emergency. 



Alcohol and the Nervous System. Alcohol, as already 

 shown, injures practically all portions of the body; but it 

 has its worst effects upon the nervous system. Through 

 its action on this system, it interferes with the circulation 

 of the blood, produces a condition of " temporary insanity " 

 called intoxication, weakens the will, and eventually de- 

 thrones the reason. Worst of all, it produces a condition 

 of "chronic poisoning" which manifests itself in an un- 

 natural craving, and this causes it to be used by the victim 

 even when he knows he is " drinking to his own destruc- 

 tion." Though its use in small quantities does not, as a 

 rule, produce such marked effects upon the nervous system, 

 it develops the "craving," and this is apt in time to lead 

 to its use in larger quantities. But even if this does not 

 occur, the practice is objectionable for its unhygienic effects 



