CONTRIBUTORS TO THIS ISSUE 249 



John Riordan, B.S., Sheffield Scientific School, Yale University, 

 1923. American Telephone and Telegraph Company, Department of 

 Development and Research, 1926-. Mr. Riordan's work has been 

 mainly on problems associated with inductive effects of electrified 

 railways. 



J. H. ScAFF, B.S.E., University of Michigan, 1929; Bell Telephone 

 Laboratories, 1929-. As a member of the Chemical Laboratories, Mr. 

 Scaff has been concerned chiefly with problems relating to the effect of 

 gases on the properties of metals. 



J. C. ScHELLENG, A.B., 1915; Instructor in Physics, Cornell Uni- 

 versity, 1915-18. Engineering Department, Western Electric Com- 

 pany, 1919-25; Bell Telephone Laboratories, 1925-. Mr. Schelleng 

 has been engaged in research in radio communication and is now Radio 

 Research Engineer. 



E. E. Schumacher, B.S., University of Michigan; Research Assis- 

 tant in Chemistry, 1916-18. Engineering Department, Western 

 Electric Company, 1918-25 ; Bell Telephone Laboratories, 1925-. Mr. 

 Schumacher's work since coming with the Bell System has related 

 largely to research studies on metals and alloys. 



Erling D. Sunde, E.E., Technische Hochschule Darmstadt, 1926. 

 American Telephone and Telegraph Company, Department of De- 

 velopment and Research, 192 7-. Mr. Sunde's work has been mainly 

 concerned with inductive effects of electric railways. 



