1802. } 
fon held the prepared frog, while another 
touched the cup, no movements were ex- 
cited, but they did immediately enfue 
when both took hold of another. If both 
Jaid hold of a glafs tube, the contractions 
were likewife not excited, but they came 
on when they took an iron cylinder inftead 
of the glafs tube. The inveltigation of 
this fubjeét was farther profecuted’ by a 
feries of experiments. He firlt placed a 
frog on an electric-plate, and touched the 
animal fometimes with a conducting arch 
of iron, fomerimes with an arch that was 
but for a part electrical, fo that he brought 
one arm in contact with the copper-hook, 
which fecured the animal, the other arm 
to fhe femoral mufcles ; the movements 
were produced’ in the firft experiment, but 
in the other the animal remained motion- 
Jefs. Hence he concluded, that the mo- 
tions proceeding on the iron-plate had 
been owing to a fimilar arch reprefented 
by that plate. He likewife found, that 
different metals, joined together in a dif- 
ferent manner, were the molt efficient, 
but above all filver. The experiment 
fucceeded under water quite as well as in 
open air, It furprifed Mr. Galvani, that, 
if the hook faftened in the fpinal: marrow 
was touched, the water replacing the con- 
ducting arch would excite contraétions in 
the animal, which did not enfue on theex- 
periment being made under oi]. Our au- 
thor thought himfelf now entitled to 
affert, that there is in the animal a double 
electricity, oppofité to one another, the one 
in the mufcles, the other inthe nerves, or 
both at the fame time in either of them. 
In order to afcertain this circumftance, he 
coated the nerve or the fpine of the back 
with tin-foil, by which he found the mo- 
tions to be extremely increafed. The 
contractions, however, proceeded lefs vi- 
goroufly by coating the mufcle. If a 
part of the nerve as well as of the mufcle 
was coated with a non conducting fub- 
ftance, as filk, or pitch diffolved in oil, no 
contractions were excited, even on apply- 
ing the conduéting arch. Mr. Galvani 
allo obferved, that this animal electricity, 
as it was ftyled by him, opens itfelf an 
ealy paflage through fome condufting folid 
bodies, whereas through others it paffes 
with moyg difficulty; but the beft conduc- 
tor of this electricity is water, while oils 
deftroy the phenomena of this matter. 
‘To the conduéting property of water the 
author was inclined to afcribe the faét, 
that, having coated the fpinal-marrow, 
and feparated the lower extremities, he 
only obferved contraétions in the leg that 
was touched, which were, however, com- 
| Hifterical Account of Galvani/m. 
505 
municated to the other as foon as he had 
brought both in contatt with each other. 
Mr. Galvani. proves next, in the moft 
convincing manner, that the contra¢lions 
are nowife excited by mechanical ftimull, 
as was firft fuppofed by others. He alfo 
obferved the contractions to fucceed lefs vi- 
goroufly when the mufcles were placed on 
a glafs-panel, and the fpinal-marrow on 
an elettric¢-plate ; but they became ftronger 
after having changed that fituation: mioft 
violently, however, they were excited when 
the legs as well as the fpinal-marrow 
were placed on coated glals-panels, par- 
ticularly on giving them fome eleétrical 
ftrokes. When the nerves were entirely 
feparated from the furrounding parts, the 
contractions did confiderably increafe. 
The experiments fucceeded equally well 
with warm-blooded and with cold-bleoded 
animals. The contractions being dimi- 
nifhed, were reftored to their former vi- 
gour after a time of reft had been al- 
lowed. ah 
We mutt acquiefce in mentioning only 
the conjectures and conclufions which the 
author has drawn from his difcovery, 
without farther entering into the fubtle 
arguments he has brought forth in fupport 
of his ideas. The conclufions he builds 
on the facts related by him are as fol. 
low :—Animals are endued with a pecu- 
liar electricity, to which he gives the ap- 
pellation of animal electricity, and which 
he thinks to be contained in moft animal 
parts, chiefly, however, manifetting itfelf 
in the mufcles and nerves. It feems to be 
fecerned in the brain from the blood, 
whence it is communicated through the 
nerves to the different parts of the body, 
but it appears to refide chiefly in the 
mufcles. A mufcular fibre is fimilar toa 
{mall Leyden phial, and the nerve repre- 
fents the conduétor of the phial, and con~ 
fequently the whole mufcular fubftance is 
to be confidered as a number of Leyden 
phials, The external furface of the mutcle 
poffefles negative, the internal fubftance 
pofitive, electricity. The interior of 
nerves is compofed of a matter capable of 
s 
conducting electricity, while the exterior ” 
prevents, by the oily coating, its cffugon 
and’ difperfion. _Muaflcular motions pro- 
ceed, when the electric fluid is condufied 
from the interior of the mufcle into the 
nerve, whence it is brought back again to 
the mufcle, either through the extern:l 
fluid of the nerves or through the mem- 
branes and the adjacent parts, as it were 
through an arch, fo that, according to the 
laws of equilibrium, the fame quantity, 
may be united in the negative electric 
- part 
