developing a multiple-effect sea water conversion system, which 

 shows promise of producing fresh water for 20 cents per 1,000 gallons 

 commercially. 



The oldest method, solar distillation, is not economical, because even 

 In the Sahara the cost of a plant would be four times that of an evapora- 

 tion plant using artificial heat. Nevertheless, there are areas in the 

 world where small quantities of water are needed, but energy sources 

 and technical competence are not available. In these areas the simple 

 solar still may be a partial answer. 



Spiegler, K. S. 



Sa/t Water Purification, John Wiley and Sons, 1962. 

 Stewart, Harris B., Jr. 



Deep Challenge, Van Nostrand, 1966. 

 U. S. Department of the Interior 



Saline Water Conversion Report for 1965, Office of Saline Water, 



Washington, D. C, 1965. 



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