THE VITAL IMPORTANCE OF PURE WATER 203 



generally recognized that a modern city has no task more 

 vital than that of guarding against contaminated water. 



WILSON AVENUE WATER TUNNEL, CHICAGO 



Photographed during construction. This tunnel is 12 feet in diameter, is 

 hollowed out of solid rock 110 feet below the surface of the water, 

 and extends eight miles from the pumping station on the north shore 

 to the crib. 



Those communities that use polluted water generally have 

 a very high death rate from typhoid fever and from other 

 intestinal diseases. Moreover the industrial efficiency of 



