VOLUME XXII JULY, 1943 NUMBER 2 



THE BELL SYSTEM 



TECHNICAL JOURNAL 



DEVOTED TO THE SCIENTIFIC AND ENGINEERING ASPECTS 

 OF ELECTRICAL COMMUNICATION 



A Mineral Survey for Piezo-Electric Materials 



—W. L. Bond 145 



The Fundamental Equations of Electron Motion (Dynam- 

 ics of High Speed Particles) . . . . L. A. MacColl 153 



Quartz Crystal Applications . . . . . W. P. Mason 178 



Methods for Specifying Quartz Crystal Orientation and 

 Their Determination by Optical Means . W. L. Bond 224 



A Note on the Transmission Line Equation in Terms of 

 Impedance J. R. Pierce 263 



Abstracts of Technical Articles by Bell System Authors . 266 



Contributors to this Issue 268 



AMERICAN TELEPHONE AND TELEGRAPH COMPANY 



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