WATER SUPPLY 



supply, should be analyzed, and all the surround- 

 ings should be thoroughly examined. If your 

 spring is analyzed as wholesome, and you are sure 

 that it cannot be contaminated from some neigh- 

 bor's drainage, build over it a spring house, of stone, 

 if possible, and in this have a stone box for keeping 

 meats cool, and a tank for milk cans. 



Wells are contaminated not only by surface water, 

 by slops, and by barnyard drainage, but by sub- 

 terranean streams that encounter cesspools or other 

 contaminating substances. In this way typhoid 

 fever bacteria, as well as those which cause diarrhea, 

 dysentery, and probably other diseases are carried 

 into the human system. It is thought that such 

 epidemics as cholera are frequently caused by pol- 

 luted wells. A well must therefore not only be 

 placed on high ground, but we must make sure that 

 the under-soil strata do not seep toward it. The 

 impervious strata may slope so as to run water under 

 the soil for quite a distance and turn it into a well. 

 The ground immediately around the well should 

 slope away from it, and the waste water from the 

 well itself should not be allowed to soak down into 

 the ground, carrying with it surface impurities and 

 stagnation. But you cannot even then be sure of 



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