70 C. E. ANDERSON 
for the cloud to rise in the first place. I think 
possibly that the individual elements, both the 
small rapidly changing ones and the larger ones 
are all unstable but have a life cycle because of 
precipitation processes. It is this life cycle which 
gives them a semiperiodic appearance, somewhat 
similar to the occlusion processes that give pe- 
riodic appearance to cyclones. 
Mr. C. B. Anderson—In regard to the problem 
of bubble versus periodic motions, I thought the 
data I showed from Vonnegut’s work would indi- 
cate that if these were discrete elements, they 
could not act over a large segment of the atmos- 
phere simultaneously. Since we find the motions 
near the cloud base, within the interior of the 
cloud, and at the top to be in phase, it is very 
hard to account for this by assuming some type 
of discrete element moving upwards. 
