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Obfervations on Electricity. 279 
hoarfe or chirping noife. When the ball was lefs than two 
inches in diameter, it was ufually covered with fhort flames 
of this kind, which were very numerous. 
26. When two equal balls were prefented to each other, 
and one of them was rendered ftrongly pofitive, while the 
other remained in connexion with the earth, the pofitive brufh 
or ramified {park was feen to pafs from the electrified ball : 
when the other ball was eleCtrified negatively, and the ball, 
which before had been pofitive, was connected with the ground, 
the eleCtricity (paffing the fame way according to Franklin) 
exhibited the negative flame, or denfe ftraight and more lu- 
minous fpark, from the negative ball ; and when the one ball 
was eleCtrified plus and the other minus , the figns of both elec- 
tricities appeared. If the interval was not too great, the long 
zig-zag fpark of the plus ball ftruck to the ftrait flame of 
the minus ball, ufually at the diftance of about one-third of 
the length of the latter from its point, rendering the other 
two-thirds very bright. Sometimes, however, the pofitive 
fpark ftruck the ball at a diftance from the negative flame. 
Thefe effefts are reprefented in Plate IV. fig. 1, 2 and 3. 
27. Two conductors of three-quarters of an inch diameter, 
with fpherical ends of the fame diameter, were laid parallel to 
each other, at the diftance of about two inches, in fuch a 
manner as that the ends pointed in oppofite directions, and 
were fix or eight inches afunder. Thefe, which may be dif- 
tinguifhed by the letters P and M, Were fucceffively eleCtrified 
as the balls were in the laft paragraph. When one conductor 
P was pofitive, fig. 5. it exhibited the fpark of that eleCtricity at its 
extremity, and ftruck the fide of the other conductor M. When 
the laft-mentioned conductor M was eleCtrified negatively, 
fig. 4. the former being in its turn connected with the earth, 
S f 2 tha 
