INCREASE IN ORGANIC DISEASES 



As communicable diseases come under control, more men and women survive to ad- 

 vanced ages. More deaths, therefore, result from various diseases of old age — 

 cancer, heart disease, kidney disease and others 



The privy and the home-sewage-disposal plant found on individual farms 

 or in outlying portions of towns frequently become dangers to health. The 

 cesspool lets the raw sewage drain quickly into the ground water, where it 

 sometimes pollutes wells and springs in the vicinity. The septic tank is much 

 safer than the cesspool, for in it any harmful microbes are destroyed by anaero- 

 bic bacteria. 



In towns and cities elaborate sewer systems are Installed to remove wastes 

 from the individual homes. Some cities allow the sewage to flow into a stream 

 or lake without any treatment. This is cheap, but it makes the stream unfit 

 for bathing and swimming and fishing; and it may create a distinct nuisance. 

 Furthermore, the bacteria which live on the decaying refuse may use so much 



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