122 BELL SYSTEM TECHNICAL JOURNAL 



primary, then in cases where they are observed alone. In the closing 

 section are discussed the cases in which electromotive forces are 

 generated in solids by light. 



An Estimate of the Frequency Distribution of Atmospheric Noise.^ 

 R, K. Potter. A relation between atmospheric noise intensity and 

 frequency is estimated upon the basis of noise measurement data 

 covering the frequency range between 15 and 60 kilocycles, and 2 

 and 20 megacycles. 



6 Proc. I. R. E., September, 1932. 



