1921.] The Bighth Indian Science Congress. ci 
concentrate over a restricted path the energy extracted from 
d d, if water vapour 
hey y. 
damage by the suddenness and violence of the rainfall accom- 
panying them, but the energy they make use of is incomparably 
jess than that involved ina gently raining sky well spread ove 
Temperature 
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Fie. 4. 
& province in a normal monsoon. However great, then, may 
be our scientific interest in dust and thunder storms and other 
such small producers of rainfall, we have to recognize that the 
direction of practical enquiry lies rather in the causes of vari- 
ations in monsoon winds, cyclones and winter storms, and it 
is consequently to these that in India we have set ourselves in 
the first instance. 
21. Our business, then, has been to measure and record 
as many of the conditions in the upper-air over India as have 
