the Annual Evaporation at Liverpool, 8cc. 251 
perature of the air, the ftate of the winds, and the eva- 
poration, were nearly the fame during thefe t wo months, 
and yet the rain of Auguft was more than double that of 
July. The reafon why the greater quantity of rain had 
no more effect than the fmaller in adding moifture to 
the atmofphere, is obvious ; for on confulting my regifter 
I find, that the rain of Auguft fell in heavy fhowers, and 
ran off the ground before it could be evaporated ; while 
that of July, falling in fmall drizzling fhowers, gave 
more time for its evaporation. 
Again, the temperature of the air, the ftate of the 
W r inds, and the evaporation, were nearly the fame during 
the firft three months of the year 1773, with what they 
were during the laft three months of that year; the ftate 
of the air therefore, with refpedt to moifture and dry- 
nefs, muft have been the fame during thefe two feafons ; 
and yet the depth of rain, in one of thefe feafons, was 
much more than double what it was in the other. If 
we attend to whole years the fame obfervation is con- 
firmed. The rain of 1775 exceeded the rain of 1774 
more than eight inches; and hence it might he con- 
cluded, that the atmofphere was more moift in 1775 
than in 1774; the reverfe of this, however, is found to be 
the fa£t : for there evaporated from a conftant and deter- 
minate furface of water in 1775, full three inches more 
K k 2 than 
