CORRESPONDENCE 



HANDBOOK OF METEOROLOGY 

 I. From J. W. Red way, Meteorological Laboratory, Mount Vernon, N.Y. 

 To the Editor of Science Progress 



Dear Sir, — A review of my Handbook of Meteorology contains the 

 statement, " The causes of precipitation are less clearly set out." If you 

 have formed this opinion I certainly am glad to know it, and I appreciate 

 your frank statement ; for it is only by taking advantage of such opinions 

 that weak places can be strengthened. 



So far as cloudbursts are concerned, I plead guilty. If only I could obtain 

 definite knowledge in the problem I might make myself clear. But my 

 experience of a dozen years in a region where cloudbursts come when they 

 come has forced me to object to theories that have been advanced. One 

 meteorologist of highest repute calls the cloudburst " an exaggerated thunder- 

 storm precipitation." This might apply to the downpour of a thunderstorm 

 in the eastern part of the United States, but certainly not to the cloudbursts 

 of the western border — Arizona or California. 



The first note on p. 105 records my own experience — and that very mildly. 

 To the best of my judgment more, rather than less, than 6 inches of water 

 came down in sheets. The fact that I wish to emphasise is, that all the 

 water vapour up to cloud-height limits could not have accounted for the 

 amount of water that fell. A light drizzle continued for several hours ; there 

 was a very light fall a few miles away, but none at all across the range. 



Now, if someone will propound a theory of cloudbursts that will conform 

 to my experiences I will endeavour to express it in a style that will convey a 

 clear meaning. 



Thanking you for your note, !I am very sincerely yours, 



J. W. Red WAY. 

 Mount Vernon, N.Y. 



May 31, 1922. 



II. From E. V. Newnham, D.Sc, Meteorological Office, London 



To the Editor of Science Progress 



Dear Sir, — In the review in question it was not my intention to suggest 

 that cloudbursts are sufiiciently well understood for it to be possible to give a 

 clear and concise description of the way in which the heavy rainfall is brought 

 about. Mr. Redway's remark, however, on p. 105 of his Handbook, that 

 " All the water in an overhead saturated air at a temperature of 70° F. over 

 the area covered by the downpour would not make a rainfall sufficient to 

 account for the water dropped by a cloudburst," makes me wonder whether 



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