Abstracts of Technical Articles from Bell System Sources (01 October 1936)

Published by Macmillan Company, New York, N. Y., September, 1936. 628 ABSTRACTS OF TECHNICAL ARTICLES 629 and to that extent allows a more accurate calculation of the identity periods of the crystalline forms to be made. A partial transformation of the beta to the alpha form of guttapercha results by stretching at 80° C., although the exact conditions under which this occurs have not been determined. The identity period in the fiber direction of the beta modification is 4.77 ± 0.03 A., or double this value, and the alpha modification presents an anomaly in that two identity periods are in best agreement with the data. 

These are 9.00 dh 0.05 and 8.70 db 0.13 A. In the case of the beta modification three possible orthorhombic unit cells which are in agreement with the observed lattice plane spacings are given. Fields Caused by Remote Thunderstorms.3 K. E. GOULD. The object of the studies described in this paper was to verify the supposition that certain types of short-duration longitudinal voltages appearing in communication circuits are caused by remote thunderstorms. 

By means of simultaneous directional measurements made in the frequency range below 40 kilocycles at two points as much as 900 miles apart, thunderstorms at distances of several hundred miles from one or both of these points have been located with a degree of accuracy great enough to permit conclusive correlation of the storm locations indicated by the directional measurements with the locations of recorded thunderstorms.