Contributors to this Issue 



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-. 

 As Research Physicist, Dr. Darrow has been engaged largely in writing on 

 various fields of physics and the allied sciences. 



Thornton C. Fry, A.B., Findlay College, 1912; A.M., University of 

 Wisconsin, 1913; Ph.D., 1920. Mathematician, Western Electric Com- 

 pany, 1916-24; Bell Telephone Laboratories, since 1924. Dr. Fry is now 

 Mathematical Research Director in the Laboratories. 



C. M. Hebbert, B.S., Otterbein College, 1911; M.S., University of 

 Illinois, 1914; Ph.D., University of Illinois, 1917; Research Assistant for 

 National Advisory Committee on Aeronautics, 1919; Instructor in Mathe- 

 matics, University of Illinois, 1919-20. American Telephone and Tele- 

 graph Company, 1920-29; Bell Telephone Laboratories, 1929-. Dr. 

 Hebbert is engaged in the study of general transmission engineering prob- 

 lems. 



F. R. Stansel, B.S. in E.E., Union College, 1926; M.E.E., Polytechnic 

 Institute of Brooklyn, 1934; D.E.E., Polytechnic Institute of Brooklyn, 

 1941. Bell Telephone Laboratories, 1926-. Dr. Stansel has been engaged 

 in the design of special laboratory measuring and testing apparatus. 



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