Abstracts of Bell System Technical Papers Not 

 Appearing in this Journal 



Direct Determination of Hydrocarbon in Raw Rubber, Gutta-Percha, 

 and Related Substances} A. R. Kemp. lodochloride in glacial acetic 

 acid is shown to be a suitable reagent to determine the unsaturation 

 of the hydrocarbon in rubber or gutta-percha. The influence of time, 

 temperature, sunlight, and reagent concentration upon the reaction 

 is shown. 



Comparisons are made between iodochloride, iodobromide and 

 bromine relative to their reactions with raw rubber and some of the 

 terpenes. 



Results of analyses of several rubber and gutta-percha samples are 

 given. 



The effects of mastication and heat upon the unsaturation of raw 

 rubber are shown. 



Microtomic Preparation of Soft Metals for Microscopic Examination^ 

 F. F. Lucas. This paper outlines the apparent limitations of polishing 

 methods for preparing specimens of soft metals for metallographic 

 examination. A microtome method has been developed and its 

 successful application to the study of lead cable sheath alloys illus- 

 trated. Much time and labor are saved and results have been ob- 

 tained which were impossible by polishing methods. 



In lead-antimony cable sheath alloys a widened grain boundary 

 phenomenon was disclosed by the new method and the probable 

 nature of the structural changes determined. Changes in structure 

 due to aging are shown and those which accompany thermal or 

 mechanical treatment of the metal may be followed clearly. 



Distribution of Energy in Worked Metals.^ Lyall Zickrick and 

 R. S. Dean. The purpose of this paper is to give experimental 

 results that seem to be in accord with the theory, that in the deforma- 

 tion of a crystal the energy supplied is distributed to the atoms of 

 the lattice, probably by the forced formation of molecules. 



1 Journ. Ind. and Engr. Chem., Vol. 19, p. 531, 1927. 



'^ Institute of Metals Division, A. I. M. E., February 15, 1927. 



3 Wire, Vol. 2, p. 161, 1927. 



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