C. £. Dutton—Lfect of a warmer Climate upon Glaciers. 9 
the atmosphere. So obvious are the considerations which arise 
from this fact that no further discussion of it is necessary. 
(18.) Having found that the mean rate of precipitation would 
be largely increased by a warmer climate, the next step is to 
inquire whether the tame of precipitation would also be in- 
creased by the same cause. Here as before we must recur to 
the causes and conditions, which fix for any locality, the num- 
ber of rainy days and hours of the average year; but we only 
need to advert to them in their most general forms. We may 
recall again the statement that precipitation takes place when 
Saturated air is cooled—never otherwise. It cools when it 
moves from a place where the local conditions make it warmer, 
to a place where the local conditions make it cooler. Again 
winds from certain directions bring wet weather, while th 
double duty. In part, however, it presents independent consid- 
otly. ave 
_ erations which will be adverted to prese 
9 
