ELECTRICT Y, 
trifled negatively, the phial will be charged in the fame 
manner; but the fide that touches the conductor will he 
electrified negatively, and the oppolite fide will be elec¬ 
trified pofitively.- But, by i'nfulating the phial, and re¬ 
peating the,fame procefs, the index of the electrometer 
will foon rife to ninety degrees, yet the phial will remain 
uncharged ; becaufe the outfide, having no communica¬ 
tion with the earth, See. cannot part with its own elec¬ 
tricity, and therefore the infide cannot acquire an addi¬ 
tional quantity : but when a chain, or any other conduct¬ 
ing medium, connects the outfide of the phial with the 
table, the phial may be charged.as before. Moreover, 
if a phial be infulated, and one fide of it, inftead of being 
connected with the earth, be connected with the infulated 
rubber, whilft the other fide communicates with the prime 
conductor, the phial will be expeditioufly charged ; be- 
c.uife that, whilft the rubber exhaufts one fide, the other 
fide is ('applied by the prime conductor; and thus the 
phial is charged with its owiyeleCtricity ; or the eleCtric 
fluid of one of its (ides is thus thrown upon the other 
fide. This la ft experiment may be diveriified by inhi¬ 
biting the phial, and placing it with its wire at the dif- 
tance of about half an inch from the prime conductor, 
and holding the knob of another wire at the fame difiance 
from its outfide coating; then, upon turning the ma¬ 
chine, a fpark will be obferved to proceed from the prime 
conductor to the wire of the phial, and another fpark will 
pafs at the time from the outfide coating to the knob of 
the wire prefented towards it: and thus it appears, that 
■as a quantity of the eleCtric fluid is entering the infide 
of the phial, an equal quantity of it is leaving the out- 
flde. If the wire prefented to the outfide of the phial 
be pointed, it will be feen illuminated with a (tar; but 
if the pointed wire be connected with the coating of the 
phial, it will appear illuminated with a pencil or brufli 
of rays. 
Mr. Cavallo has deferibed the conftruCtion of a phial 
which, being charged by an electrical k s, e, in examining 
the date of the clouds, or in any other way, may be put 
into the pocket, and which will retain its charge for acon- 
fiderable time. A phial of this kind has been kept in a 
charged ftate for fix weeks. - See his Electricity, p. 340. 
Mr. Cavallo alfo deferibes a method of repairing coated 
phials that have cracked by accident. He firft removes 
the outfide coating from the fractured part, and then 
makes it moderately hot, by holding it to the flame of a 
candle; and whilft it remains hot, he applies, burning 
fealing-wax to the part, (o as to cover the fraCture en¬ 
tirely ; obferving that the thicknefs of this wax coating 
may be greater than that of the glafs. I.aftly, he covers 
all the fealing-wax,.and alfo part of the furface of the 
glafs beyond it, with a compolition made with four parts 
of bees-wax, one of refin, one of turpentine, and a very 
tittle oiltof olives; this being fpread upon a piece of oiled 
lilk, he applies it in the manner of a plafter. In this way 
feveral phials have been fo effectually repaired, that after 
being frequently charged, they were again broken by a 
fpontaneous difeharge, but in a different part of tlje glafs. 
Fig. 8. in the Engraving, exhibits another Leyden 
phial, which is called the Jpottcd bottle , becaufe it is only 
coated with fmall pieces of tin-foil, placed at a little dif- 
tance from each other. If this bottle be charged in the 
ufual manner, firong fparks of electricity will fly from 
one fpot of tin-foil to the other, making the puflage of the 
fluid on the outfide very vifible. Dilcharge this bottle, 
by bringing a pointed wire gradually near the knob, and 
the uncoated part of tire glafs between the fpots will be 
pleafingly illuminated, and the noife will refemble that 
of fmall fired crackers. If the jar be difeharged fuddenly, 
the outfide furface will appear illuminated. To produce 
thefe appearances, the glais mu ft be very free from moif- 
ture. If a phial uncoated on the outfide be held in the 
hand, and its knob prefented towards an electrified .con¬ 
ductor ; the eleCtric fluid, while it is charging, will pafs 
from the outfide to the hand, in a pleating manner; on 
Vox. VI. No. 360. 
41 3 
the difeharge, beautiful ramifications will be feen upon 
the uncoated part of the bottle. 
This experiment may be Hill farther purfued by fuf- 
pending two fets of bells from a Leyden bottle placed 
horizontally ; .oneTet connected with the infide, the other 
with the outfide, as reprefented by fig. 9. Hook up the 
chain from the bells communicating with the infide, that 
they may have no connection with the'table; charge the 
bottle in the, ufual manner; during the charge, the fet 
fuf'pended from the outfide will continue to ring. After 
the bottle is charged, unhook the wire of the bells fuf- 
pended from the infide. Touch now the wire A, and the 
bells will ceafe ringing, but the other -fet will begin to 
aCt; take the finger from A, and apply it to B, and the 
bells at B will be quiet, while thole at A will be fet 
ringing; and fo on alternately, till the butfle is difeharged 
of the eleClrical fluid. 
The mofl formidable charge that cap. be given to the 
eleCtrical apparatus, is by means of the eleCtrical battery, 
which confifts of a number of Leyden jars connected to¬ 
gether in a box. The bottom of the box is covered with 
tin-foil ; from thefe a hook projects on the outfide of the 
box, by which any fubftance may be connected with the 
outfide of the jars; their infides are all connected by wire 
or fome metallic communication; by means of which a 
great number of very interefting experiments in electri¬ 
city are performed ; and though it be a formidable ap¬ 
pendage to an eleCtrical machine, yet it,cannot be faid 
that the apparatus is complete without it. Its effeCts in 
exploding various bodies, in firing gunpowder, in melt¬ 
ing wires, and in imitating all the effects of lightning, are 
highly curious and interefting. 
In an eleCtrical battery, the jars are fo arranged that 
the whole may be charged at tire fame time, and dif¬ 
eharged in an inftant; Co that the whole power of the 
eleCtric fluid accumulated in them, may be at once ex¬ 
erted upon the fubftance expofed to the (bock. The 
eleCtrical battery reprefented at fig. 10, in the preceding 
engraving, confifts of nine jars connected together by the 
wires a, b, c, d, e,f ? g, h, i ; all of which are fattened into 
the (toppers of the bottles, and meet at top in the brafs 
ball. Thus a communication is made between all the 
infide coating of the jars, while their outfide coatings are 
connected by the bottom of the box in which they (land. 
In one fide of the box, near the bottom, is an hole through 
which a brafs hook pafies, and which communicates with 
the metallic lining of the box, and confequently'with the 
outfide coatings of the jars. To this hook a wire or chain 
is occafionally connected when a difeharge is made ; and, 
for the more convenient making of this difeharge, a ball 
and wire B, proceed to a convenient length from the cen¬ 
ter ball A. When the whole force of the battery is not 
required, one, two, or three, jars may be rendered neu¬ 
tral, by prefling down the wires belonging to them, until 
their extremities can (lip out of their refpeCIive holes in 
the brafs ball, and then turning them into fuch a pofture 
that they cannot have any communication with the bat¬ 
tery. The number of jars reprefented in this figure is 
rather fmall for fome purpofes ; but it may be enlarged 
at pleafure. 
The deElrical kite , was contrived by Dr. Franklin, as be¬ 
fore-mentioned, to verify his hypotbefis of the identity of 
electricity and lightning. It confided of a large thin (ilk 
handkerchief, extended andfaftened at the four corners o 
two (lender ftrips of cedar, and accommodated with a tail, 
loop, and ftriqg, fo as to rife in the air like a common paper 
kite.To the top of the upright (lick of the crofs was fixed 
a very fharp-pointed wire, riling a foot or more above the 
wood; and to the end of the twine, next the hand, a fi!k 
ribband was tied. From a key fufpended at the junction 
of the twine and filk, when, the kite is raifed during a 
thunder-dorm, a phial may be charged, and electric fluid 
collected, as is tifually done by means of a cylinder or 
globe in the electrical machine. Kites made of paper, 
covered with varnifli, or with well-boiled linfeed oil, to 
5 N preferve 
