RAIN AND ITS ORIGIN IN THUNDERSTORMS. 413 



important bearing on the questions discussed in this paper. A simple method might 

 be based on a comparison of the rates of ascent of balloons during normal weather and 

 during thunderstorms. The retardation due to the water attaching itself to the 

 balloon would have to be estimated, but in spite of the uncertainty arising from this 

 cause, valuable information would probably be obtained by a systematic series of 

 observations. 



