o4 T HE:O RY “or 
ftored to their natural ftates, but either by immerfing them 
fingly under water, or by replacing the whole apparatus 
and filling both the jars, and the box which contains them, 
with water as at firft, and introducing a metalline conduc- 
tor betwixt the water without the jars and any one of the 
wires which conneé their infides ; then the whole will be 
inftantly difcharged with an explofion*. 
To apply thefe obfervations to the prefent fubje&t, we 
may regard every particle of a body of pure, but inci- 
dentally eletrified air, in the fame light with one of the 
jars in the battery aforefaid, which, after having been 
charged, is deprived of its adventitious coatings: Each 
particle, like one of thofe jars, will retain the ftate it may 
happen to be in, fo long as it remains deftitute of a con- 
duéting appendage. But when, and by what means foever, 
a fufficiency of moift vapors fhall become interfperfed 
amonett thefe particles of air to furnifh them feverally with 
non-eleétric coatings, and by the nearnefs or contiguity of 
thefe vapors to form a communication from one to another 
throughout the whole, they will then be in the fame con- 
neéted ftate with the jars in the battery, when complete 
in every part, and charged; and like thofe jars be the 
particles ever fo numerous, they will be in a capacity of 
jointly receiving or communicating the electric fire. And 
as, by the addition of jars in the conftruction of the bat~ 
tery, the explofion at the difcharge may be increafed inde- 
finitely, fo will the violence of the explofion from a thun- 
der cloud be increafed in proportion to its extent, and to 
the multitude of aerial particles together with their ap- 
pendant vapors of which it confifts, and which are fo con- 
nected as to be capable of uniting in the fame difcharge. 
But as a thunder cloud is not ufually formed at once, but 
by degrees, fmaller clouds generally forming themfelves 
in 
* Thefe experiments I never faw particularly made, but the conclufions neceflarily follow 
from fome which I have feen, as well as from thofe pointed out above. 
+ Pure as to the purpofes of electricity, or free from conducting vapors; perhaps pure ele- 
mentary air is not to befound in our atmofphere. 
