SUPPLYING WATER TO POPULOUS COMMUNITIES 199 



man's great problems. Rome received its water supply by 

 aqueducts from nineteen different sources, and some of 

 these aqueducts were in use for fifteen centuries. The 

 ruins of aqueducts built by the Romans are to-day among 

 the most picturesque sights of the Italian and Spanish land- 

 scapes. Eighteen great water cisterns, remarkably well 

 preserved, are the only remains of the once thriving city of 



STRETCH OF A ROMAN AQUEDUCT NEAR N!MES, FRANCE 



Carthage on the North African coast. Near Tunis may be 

 seen a stretch of the ancient aqueduct that brought water 

 to these cisterns from the mountains thirty-five or forty 

 miles to the south. 



Springs and shallow wells have always furnished water 

 to favorably situated rural districts and sometimes to small 

 cities. Only in recent times have deep wells been sunk 

 and water lifted from great depths. Modern large cities 

 have seldom found supplies of water from underground 

 sources adequate to the demands of manufacturing and 



