THERMODYNAMICS OF ATMOSPHERE VON BEZOLD 279 



(3) Such variations of atmospheric pressure and barometric 

 steps occur frequently during thunderstorms and of magnitudes 

 such as without difficulty may be referred back to supersaturation 

 or subcooling. 



(4) It is also a fact that during thunderstorms the conditions 

 that favor the existence of such unstable conditions are fulfilled, 

 especially should subcooling occur very frequently in the higher 

 portions of thunder clouds. 



(5) Since the dissipation of such conditions must produce sudden 

 warming in individual locations, therefore by such processes we 

 must explain the peculiar changes of form that we observe in the 

 thunderstorm cumuli and which we cannot consider as a simple 

 consequence of a steadily ascending current even when this ascent 

 occurs in connection with vortex motions. 



(6) The formation of sleet and hail may without difficulty be 

 referred back to subcooling. 



