29 3 Dr. Eqfon on the Afcent of Vapour. 
The able Nollet has proved, that water elec¬ 
trified, will evaporate fafter, than water which is 
not electrified. Does it not follow, that the 
more electric matter is in the air, the quicker 
the evaporation of water will be ? And Mr. 
Cavallo has proved, that at all times the atmo- 
fphere is electrified, but much ftronger in frofty, 
than in warm weather; and by no means lefs in 
the night than in the day: it is like wife ftronger 
in elevated, than in low places. From thefe 
faCts, we may be enabled to account, why 
evaporation is carried on during very cold 
•weather. All the heat contained in water, 
above what is fufficient to keep it in a fluid 
Hate, will convert it into vapour; which, in a 
north or north eaft wind, when the ele&ric matter 
greatly abounds, will be carried off with much 
rapidity; and, by the power of ele&ricity, will 
be rendered ftill lighter, the higher it afcends; 
each particle repelling each other, and prevent¬ 
ing the cold from condenfing the vapour, in its 
afcent through the cold regions of the atmo- 
fphere. The higher it rifes, the more fpace 
there is for expanfion ; and the more it is ex¬ 
panded, the clearer will the atmofphere appear, 
and, probably, the higher the mercury will rife 
in the barometer. 
It likewife appears, that the eleCtric matter 
is more fenfible near the lurface of the earth, in 
cold 
