435. 
ELECTRICITY. 
between the ftp'p'ermod-and lowed: plate; and, if 
one hand be applied to the latter, and the other to the 
limbed'metal, an eleftric (hock will be perceived, which 
jiiay be repeated as often as the contaft is renewed. The 
in'.enfity of the charge, however, is fo low, that it cannot 
penetrate the dry fkin ; it will therefore be neceflary to 
wet both hands, and to grafp a piece of metal in each, in 
order to produce the defired effect: its power may be 
confiderably increafed, both by an elevation of tempera¬ 
ture, and by augmenting the number of pieces that com- 
pofe the pile. Thus twenty pieces of each will emit a 
fhock, that is very perceptible in the arms ; it one hun¬ 
dred tie employed, a very fevere but tremulous and con¬ 
tinued fenfation will extend even to the (boulders; and, 
if the furface of the fkin be broken, the aftion of the 
eleftric fluid will be uncommonly painful. The fenfation 
of a fliock with this apparatus, does not materially difFer 
from that produced by two Ample coated plates; but it 
may be effected in various ways, efpecially if one or both 
hands be applied in a wet (late to the lowed: plate of the 
pile ; or any part of the face be brought-in contadl with 
a wire communicatingwith the top piece. Or if a wire 
be held between the teeth, fo as to red upon the tongue, 
that organ, as well as the lips, will become convulfed, 
the fpark will appear before the eye, and a very pungent 
tade will be perceived in the mouth.—See figures of the 
Voltaic pile in the Eleftricity Plate III. fig. 22, and 2;. 
As the apparatus lofes its energy, in proportion as the 
fubdances laid on each other become dry, M. Volta en¬ 
deavoured to prevent this effeft by indofing the pile in 
wax. He contrived to inclofe in this way two columns, 
each compofed of twenty plates, which added perfedtly 
well during feveral weeks, and which, he had reafon to 
expedt, would continue to do fo for the fpace of feveral 
months. The particular combination which he confiders 
as the mod ufeful, is a battery formed by a range of glaf- 
fes, or cups, fimilar to that of the Leyden jars, and con¬ 
taining warm water or brine. Into each of thefe a plate 
of diver, and another of zinc, are plunged, but without 
reciprocally touching each other. Between thefe glades, 
or cups, metallic communications are edublidied, and dif- 
pofed in fuch a way as that, provided they reach, on the 
one hand, the zinc contained in one of the glades, they 
fhould reach the diver in the other; and that from the 
zinc in the latter they fhould extend to the diver in the 
one by which it is followed ; and thus confecutively 
throughout the whole of the aflemblage. When any one 
places himfelf in the range of the battery, between the 
firft and the lad of the glades, he feels the-fliock. It is 
edential that the plates of metal, plunged in the fluid, 
flfould have, at the lead, a fquare inch of furface. With 
refpeft to the communications from one of the glades, or 
cups, to another, they may have as fmall an extent as 
the operator may wifh. This is called the Voltaic battery. 
Tn the lifting of the French national inflitute, on the 
7th of November, i8or, M. Volta read a memoir, con¬ 
taining the detail and refults of his new experiments made 
by this apparatus ; which tended to bring frefh and flrik- 
ing evidences of the identity of the galvanic and eleftric 
fluids, agreeably to the hypotheds he had invariably 
maintained. Thefe proofs were fo fatisfaftory, that the 
gold medal was unanimoudy decreed to the learned pro- 
fedbr of Pavia. A flriking feature adduced by Volta 
was, that if two diverfe metals, infulated, and po He fling 
their natural quantity only of eleftricity, be brought in 
contaft, it will be found that, as foon as they are with¬ 
drawn from this contaft, they will poflefs different dates 
of eleftricity, or, in other words, one of them will be in 
the pofltive, the other in the negative, date. Thus, in 
the mutual contaft of copper and zinc, the copper be¬ 
comes hegative, as to its eleftricity, and the zinc pofi- 
tive. The development of the eleftric fluid is confe- 
quently independent of any humid conduftor. All the 
■ether fafts connefted with this leading one, the inflitute 
afeertained to be "incontedible, The refult was there¬ 
fore declared fo be, “ tluil tire fluid to which the nrmf 
cular contractions, and the phenomena of the pile, are 
a fc rib able, notwitliftanding it has long been confidered as 
a particular fimd, is-merely the Common elettric fluid, put 
in aftion by a caufe, the nature of which is unknown, 
but the effects of which we evidently fee.” 
This intereding hifeovery foon gave rife to feveral 
others, which are principally due to our own country¬ 
men. Mr. Carlifle, and Mr. Nicholfbn, Tucceeded- in 
the fame experiments in England, that profelfor Volta 
had made in Italy and France. At a very early part of 
the invedigation, the pile having been formed, and -the 
contafts fecured by placing a drop of water upon the up¬ 
per plate of the pile, .a difengagement of gas was ob- 
ferved round the condufting wire. The gas, though 
minute in quantity, fecme.d to Mr. Nicholfon to have the 
fmell of hydrogen, when the wire of communication was 
fleel. This, with feme other fafts, led him to pro pole 
to break the circuit, by the fubfldtution of a tube of wa¬ 
ter between two wires. Accordingly, a brafs wire thrptigh- 
each, of two corks was inferred at the oppofrte ends ot a 
gdafs tube about half an inch in diameter, filled between 
the corks with water: the diflance between the points of 
the wires in the water, was about an inch and three quar¬ 
ters. This compound difeharger was applied fo that the. 
external ends of its wire were in contaft with the two 
extreme plates of a pile of thirty-fix half-crowns with 
correfpondent pifeces of zinc and padeboard. A dream 
of minute bubbles immediately began to flow from the 
point of the lower wire in the tube, which communi¬ 
cated with the diver, and the oppodte point of the upper 
wire became tarnifhed, firfl deep orange, and then black. 
On reverfing the tube, the gas came from the other point, 
which was now lowed:, while the upper, in its turn, be¬ 
came tarniflied and black. Reverfing the tube again, the 
phenomena again changed their order. In this (late the 
whole was left for two hours and a half. The upper 
wire gradually emitted whitifli filmy clouds, which, to¬ 
wards the end of the procefs, became of a pea-green co¬ 
lour, and hung in perpendicular threads from.the extreme 
half-inch of the wire, the water being rendered femi- 
opaque by what fell off, and in a great part lay, of a pale 
green, on the lower furface of the tube, which, in this 
difpofition of the apparatus, was inclined about forty de¬ 
grees to the horizon. The lower wire, three quarters of 
an inch long, conffantly emitted gas, except when an¬ 
other circuit, or complete wire, was applied to the ap¬ 
paratus; during which time the emiflion of gas was fuf- 
pended. When this lad-mentioned wire was removed, 
the gas re-appeared as before. The produft of gas, 
during the. whole two hours, and a half, was two-thir¬ 
tieths of a cubic inch. It was then mixed with an equal 
quantity of common air, and exploded by the application 
of a lighted wax.ed thread'. 
Meifrs.-Carlifle and Nicholfon were led, by reafoning 
on the firft appearance of hydrogen, to expeft a decom- 
polition of water; but it was with no little furprife that 
they found the hydrogen extricated at v the contaft with 
one wire, while the oxygen fixed itfelf in combination 
with the other wire at the didance of almoft two inches. 
As the didance between the wires formed a flriking fea¬ 
ture in this refult, it became dedrable to afceitain whe¬ 
ther it would take place to greater diflances.. When a 
tube three quarters of an inch in diameter, and thirty-fix 
inches long, was made life of, the effeft failed, though 
the very fame wires, inferted into a fliorter tube, operated 
very brifkly. The experiment being tried with tinftnre 
of litmus in place of water, and the oxydating wire, 
namely, from the zinc fide, being lowed in the tube, it 
changed the tinfture red in about ten minutes as high as 
the upper extremity of the wire. The other portion re¬ 
mained blue. Hence it fee ms either an acid was formed, 
or that a portion of the oxygen combined with the lit¬ 
mus, fo as to produce the effe.ft of an add. 
It may he here offered as a general remark, that the 
1 eleftric 
