 
		 
		 
		Fairmount and vicinity, 1839
 
		Isometrical View of Fairmount Water Works, 1843
 
		Fair Mount Water Works engine house, 1819
 
		Wooden Water Pipe, removed from Market Street, December 6, 1901
 
		Bethlehem Water Works, 2011
 
		Roman Aqueduct in Segovia, Spain
 
		Main Pumping Stations for Philadelphia Drinking Water
 
		Volume of Sludge from 1,000,000 Gallons of Sewage
 
		Diagram Showing Rate Between Bulk of Wet Sludge and Its Percentage Moisture
 
		Sludge Drying Beds, Essen Nord, Germany
