CONTRIBUTORS TO THIS ISSUE 1255 



transmission theory, the application of Boolean algebra to switching, number 

 theory in cable splicing, and combinatorial and probability studies of traffic. 

 He is a member of the Amer. Math. Soc, Math. Assoc, of America, Inst, of 

 Math. Statistics, and Fellow of the Amer. Assoc, for the Advancement of 

 Science. 



A. A. RoETKiN, B.E.E., Ohio State University, 1927; M.Sc, 1929. Bell 

 Telephone Laboratories, 1929-. With the Laboratories Mr. Roetkin has 

 worked on overseas radio telephone receivers, ultra-high frequency, point- 

 to-point radio telephone service, pulse multiplex microwave radio repeaters 

 for the armed forces, and microwave radio-relay systems. He is a member 

 of the Institute of Radio Engineers. 



Thomas Shaw, S.B., Massachusetts Institute of Technology, 1905. Ameri- 

 can Telephone and Telegraph Company, Engineering Department, 1905-19; 

 Department of Development and Research, 1919-33. Bell Telephone Labora- 

 tories, 1933-48. Mr. Shaw's active telephone career was mainly concerned 

 with loading problems in telephone circuits, including the transmission and 

 economic features of the loading apparatus. The article which is concluded 

 in this issue was started shortly before his retirement in 1948. 



K. D. Smith, B.A., Pomona College, 1928; M.A., Dartmouth, 1930. Bell 

 Telephone Laboratories, 1930-. Consultant to National Defense Research 

 Council, 1941-44. Awarded Joint Army-Navy Certificate of Appreciation 

 for Scientific Achievement following World War II. With the Laboratories 

 Mr. Smith has been concerned with the coaxial cable system, radar bombing 

 equipment, broad band microwave radio system, and transistors. He is a 

 Senior Member of the Institute of Radio Engineers. 



R. L. Wallace, Jr., B.A. summa cum laude, physics and mathematics, 

 University of Texas, 1936; M.A., physics, 1939; Special Research Associate, 

 Harvard, 1941-45. Bell Telephone Laboratories, 1946-. Mr. Wallace's work 

 with the Laboratories has been chiefly concerned with magnetic recording 

 and transistors. He is a member of the Acoustical Society of America, Phi 

 Beta Kappa, and Sigma Chi. 



E. J. Walsh, Bell Telephone Laboratories, 1928-. Mr. Walsh's work with 

 the Laboratories has been chiefly on vacuum tube design, magnetrons, 

 proximity fuse tubes, reflex oscillators and close-spaced fine- wire grid tubes. 



