Contributors to this Issue 



C. B. Aiken, B.S., Tulane University, 1923; M.S. in Electrical Com- 

 munication Engineering, Harvard University, 1924; M.A. in Physics, 

 1925 ; Ph.D., 1933. Geophysical research and exploration with Mason, 

 Slichter and Hay, Madison, Wisconsin, 1926-28. Bell Telephone 

 Laboratories, 1928-. Dr. Aiken has been engaged in work on aircraft 

 communication equipment, broadcast receiver design, centralized radio 

 systems and common frequency broadcasting. 



A. W. Clement, B.S. in Electrical Engineering, University of Wash- 

 ington, 1925; M.A., Columbia University, 1929. Bell Telephone 

 Laboratories, Apparatus Development Department, 1925-. Mr. 

 Clement has been engaged in the development of various types of trans- 

 mission networks, such as electric wave filters and equalizers. 



Karl K. Darrow, B.S., University of Chicago, 1911; University of 

 Paris, 1911-12; University of Berlin, 1912; Ph.D., University of 

 Chicago, 1917. Western Electric Company, 1917-25; Bell Telephone 

 Laboratories, 1925-. Dr. Darrow has been engaged largely in writing 

 on various fields of physics and the allied sciences. 



L E. Fair, B.S., in Electrical Engineering, Iowa State College, 1929. 

 Bell Telephone Laboratories, Radio Research Department, 1929-. 

 Mr. Fair has been engaged in experimentation on piezo-electric crystals 

 for frequency control. 



Frank Gray, B.S., Purdue, 1911; Ph.D., University of Wisconsin, 

 1916. Western Electric Company, Engineering Department, 1919-25. 

 Bell Telephone Laboratories, 1925-. Dr. Gray has been engaged in 

 work on electro-optical systems. 



H. S. Hamilton, B.S. in Electrical Engineering, Tufts College, 

 1916. American Telephone and Telegraph Company, Engineering 

 Department, 1916-18; Department of Development and Research, 

 1918-34. Bell Telephone Laboratories, 1934-. Mr. Hamilton has 

 been engaged exclusively in toll transmission work, including telephone 

 repeaters, program transmission and carrier telephone systems. 



F. R. Lack, B.Sc, Harvard University, 1925; Engineering Depart- 

 ment, Western Electric Company, 1913-22; First Lieutenant, Signal 

 Corps, A.E.F., 1917-19; Harvard University, 1922-25. Bell Tele- 



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