CHAPTER IV 



DRINKS AND NARCOTICS 



33. Pure Water. The clear and sparkling water of 

 our springs, wells, and lakes, that tastes so good and 

 forms really the only drink necessary for man and 

 beast alike, is by no means pure to the chemist. 

 Water that is chemically pure, distilled water, is not 

 found in nature, neither is it pleasant to drink, for it is 

 flat and tasteless. What is in the spring water that 

 we thought was pure and is so agreeable to the taste ? 

 When it is carefully examined by a chemist, it is found 

 to contain minerals of various kinds, and air. The 

 most common minerals are lime, soda, potash, iron, 

 magnesia, and sulphur. 



The water that is most healthful is not absolutely 

 pure but contains air and many mineral substances 

 that are valuable to the body. It is only when these 

 minerals are too abundant, and especially when water con- 

 tains disease germs, that it becomes dangerous to drink. 



1. Dissolve salt or sugar in water until you can easily taste it. 

 Then heat the solution to the boiling point and collect the vapor 

 that is given off. Do you detect any taste ? What has become of 

 the salt or sugar ? 



2. Evaporate the entire solution. Do you have any solid left ? 



30 



