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The fame oblervations that lead us to the difcovery 
of any power, if followed out with due attention, 
may ferve to inftruCt us in the laws of its action ; and 
if we can attain a fufficient knowlege of thofe laws, 
however ignorant we may be of the peculiar manner 
in which the power exerts itfelf, we may be, by that 
means, enabled to trace it through its various opera- 
tions. 
The laws of nature are few and fimple. It is only 
from the variety of circumftances, under which the 
refpeCtive powers are exerted, that the phenomena of 
nature are multiplied. The powers of mechanic mo- 
tion, thofe I mean by which bodies aCt upon one an- 
other in impulfe or preflure, are found to be under 
the direction but of three general laws; and from 
thence is deduced a moft extenfive branch of natural 
knowlege. 
The laws that regulate the powers, by which bo- 
dies aCt at a diftance upon one another, when we 
come to be better acquainted with them, may be 
found to be not more numerous or complex. What 
appears wonderful to us, is, that bodies fhould at all be 
capable of acting upon one another at a diftance : But 
are we not equally ignorant of the manner, in which 
the powers of motion are exerted, when the bodies 
are in actual congrefs ? Daily experience convinces 
us of the faCt in this cafe ; and in the other, repeated 
experiments, and frequent obfervations, leave us little 
room to doubt, that there are powers, which, when 
lodged in one body, are capable of being exerted 
upon another at a diftance. 
The powers of electricity are found to be of this 
nature. When either of thofe powers prevails in a 
7 body. 
