WATER WASTE CAUSES FOR USES OF METERS SOURCES OF WATER SUPPLY RAIN WATER SUPPLY NOT RELIABLE EASILY POLLUTED FILTERING NECESSARY DESIRABLE FOR LAUNDRY PURPOSES SURFACE WATER STREAMS LAKES IMPOUNDING RESERVOIRS SOURCES OF IMPURITIES IN SURFACE SUPPLY GROUND OR SUBSOIL WATER WELL WATER SPRING WATER TEMPERATURE IN WELLS SHALLOW AND DEEP WELLS CONSTRUCTION OF WELLS SOIL AS A FILTER METHODS OF PURIFICATION NATURAL METHODS OF WATER PURIFICATION BY FREEZING SELF-PURIFICATION WATER VEGETATION DILUTION STORAGE AND SEDIMENTATION SUNLIGHT ARTIFICIAL METHODS OF WATER PURIFICATION DISTILLATION BOILING FILTRATION CHEMICAL PURIFICATION SWIMMING POOLS SANITATION OF SWIMMERS INSTRUCTED IN POOL SANITATION SEWAGE AND REFUSE DISPOSAL METHODS OF SEWAGE DISPOSAL DRY WET SEWAGE PURIFICATION SCREENED SEPTIC METHOD REFUSE DISPOSAL INCINERATION CITY COLLECTORS CHAPTER VII WATER GENERAL CONSIDERATIONS Necessity for Proper Supply One of the most important requisites in maintaining the organization of the material in the living body is a proper supply of water. It is absolutely indispensable to the expression of animal and vegetable life. Although not classed as a food it enters into the composition of food and hence becomes an essential article of diet. The greatest value has always been placed upon a sufficient supply of pure water. The history of the race shows that the earliest settlements were made with a view to obtaining a supply of water; they were either on waterways or in places where water was easily obtainable from springs or shallow wells. Water is needed not only as an article of diet, but it is also required for sanitary purposes: for cleansing the body externally, for washing clothes, and also for sprinkling streets and for other purposes such as sewage disposal in the thickly populated centers. Even in ancient times great sums of money were expended for the public supply of water. History of Public Water Supply A bit of history on this subject might be of interest to some. It is asserted by historians that there are aqueducts in China dating back to prehistoric times. Channels cut in solid rock have been revealed in Jerusalem in recent excavation which indicate that they were used for conveying the water supply from the country near Bethlehem and Hebron. There have been found in these excavations channels of earthen pipes cemented together and covered with rough rocks. The fact is also quite well established that water was brought to Athens from Mount Hymettos and Mount Pentelikon.