S..iitIisonian Report, 1935. — Johnson 



Plate 1 





1. Tiio cloiKl IracI: of a cosmic ray consisting of a row of water droplets condensed upon air molecules 

 which have been ionized by the ray. 



X' 





2 A cosmic ray "shower" photographed by Ulackett and Occhialini The existence of spcondarv rav.: 

 (pfocTe^S T^^'SllS^:^' ^'"-^ ^'^-"^- - - — »f anaiyz^in^g 'Kr^/^^lTcofr^I^ r^a^s^ 



