FURTHER READING 



This rather technical book describes the basic prin- 

 ciples and operation of electronic sonar systems as 

 they are used on ships. It explains the Doppler effect 

 and other basic phenomena of echolocation with spe- 

 cial reference to underwater sound. 



Hurley, P. M.: How Old is the Earth. New York: 

 Science Study Series, Doubleday Anchor Books, 1959. 



This modem book on radioactivity as an energy 

 source in the earth and as means of measuring time 

 also includes a piece on seismic waves. 



Pierce, J. R., and David, E. E., Jr.: Man's World of 

 Sound. New York: Doubleday and Company, 1958. 

 A semi-popular book describing at an elementary 

 level the physical properties of sound waves. It dis- 

 cusses such matters as interference, the propagation 

 of sound, standing waves, etc., in a way which any 

 student of secondary school physics should have litde 

 diflBculty in understanding. 



Ridenour, L. N. (Editor) : Radar System Engineering, 

 New York: McGraw-Hill, 1st Edition, 1947. 



This is a general description of the radar systems de- 

 veloped during World War II by the Radiation Labo- 

 ratory at M.I.T. While parts of it are quite technical, 

 many chapters can easily be understood by any seri- 

 ously interested reader of this monograph. Radar sets 

 and systems are described and illustrated in sufi&cient 

 detail to permit, for example, the sort of comparison 

 with biological systems that were discussed in Chap- 

 ter 5. 



Rummell, J. A.: "Modern Sonar Systems." Electronics 

 (Engineering Edition), January 1958, pages 58-62. 

 A brief survey of the apparatus used in sonar systems. 



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