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Ail which has been here faid relating to the flow" 
jng out of eledricity from overcharged bodies, hold® 
equally true with regard to the flowing in of eledri- 
city into undercharged bodies. 
But a circumftance which I believe contributes as 
much as any thing to the quick difcharge of eledri- 
city from points, is the fwift current of air caufed by 
them, and taken notice of by Mr. Wilfon and Dr. 
PriefUy {vide Prieftly, p. 1 17 and 591) j and which is 
produced in this manner. 
If a globular body A B D is overcharged, the air 
dole to it, all round its furface, is rendered over- 
charged, by the eledric fluid, which flows into it 
from the body; it will therefore be repelled by the 
body i but as the air all round the body is repelled 
with the fame force, it is in equilibrio, and has no 
tendency to fly off from it. If now the conical point 
A C B be made to fland out from the globe, as the 
fluid will cfcape much fafter in proportion to the 
furface from the end of the point than from the refl: 
of the body, the air clofe to it will be much more 
overcharged than that clofe to the refl of the body j 
it will therefore be repelled with much more force j 
and confequently a current of air will flow along the 
fides of the cone, from B towards C ; by which 
means there is a continual fupply of frefli air, not 
much overcharged, brought in contad with the point; 
whereas otherwife the air adjoining to it would be fo 
much overcharged, that the eledfricity would have 
but little difpofition to flow from the point into it. 
The fame current of air is produced in a lefs 
degree, without the help of the point, if the body, 
inftead of being globular, is oblong or flat, or has 
knobs 
