FURTHER READING 



Witcher, C. M., and Washington, L.: "Echo-Location 

 for the Blind." Electronics, December 1954, pages 

 136-137. 

 A brief but complete description of one of the more 

 successful sound-generating devices used by blind 

 people to find their way about. The late C. M. Witcher 

 was himself blind and he devoted his engineering tal- 

 ents to improving such devices for his own use and 

 for the benefit of other bUnd people. 



Zahl, P. A. (Editor) : Blindness. Princeton, New Jersey: 

 Princeton University Press, 1950. 



A collection of articles by different authors discussing 

 the most important problems faced by bUnd peo- 

 ple, education for the blind, vocational rehabilitation, 

 talking books, guide dogs, guidance devices, and the 

 remote possibility of direct stimulation of the optic 

 nerves or visual areas of the brain. 



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