#62] 
erroneous, but has also made known 
several important facts, in addition 
to those which had been discovered 
by that author.” As he appears, 
however, from these letters, to have’ 
fallen into some mistakes himself, 
and has certainly not exhausted the 
subject which he has treated in 
them, I shall venture to communi- 
cate to this learned body a few ob- 
servations I have made respecting 
it, which may contribute both to 
correct his errors, and to increase 
our knowledge of the,cause of those 
motions, which have been attributed 
by Mr. Galvani and others to an 
animal electricity. These obser- 
vations will be so arranged, as to 
furnish answers, more or less satis- 
factory, to the following questions : 
does the incitement of the influence 
which, in Mr. Galvani’s experi- 
ments, occasions the muscles of ani- 
mals to: contract, either wholly, or 
in part, depend. upon any peculiar 
property of living bodies? What 
are the conditions necessary for the 
excitement of this influence? Is it 
electrical ? ' 
- When a muscle contracts upon a 
connection being formed, by means 
of one or more metals, between its 
external surface and the nerve 
which penetrates it, Mr. Galvani, 
contends that, previously to this 
effect, the inner and outer parts of 
the muscle contain different quan- 
tities of the electric fluid; that the 
nerve is consequently in the same 
state, with respect to that fluid, as 
the internal substance of the muscle; 
and that, upon the application of 
one or more metals between its 
outer surface and the nerve, an 
electrical discharge takes place, 
which is the cause of the contrac- 
tion of the muscle. In shsrt, he 
supposes a complete similarity to 
ANNUAL REGISTER, 
1795. 
exist between a muscle, in a proper |i 
condition to exhibit this appears | 
ance, and a charged Leyden phial; 
the nerve of the former answering, |} 
as faras/his experiments are con= {f 
cerned, the same purpose as the 
wire, which is connected with the in- 
ternal surface of the latter. 
Now, if this were just, sucha fj 
muscle ought to contract, whenever |; 
a communication is formed between — 
its internal surface and the nerve, 
by means of any conductor of elece | 
tricity ; and accordingly Mr. Volta, 
who toa certain extent adopts Mr. 
Galvani’s theory, asserts this to be 
the case, as often as the experiment 
is made upon an animal which has 
been newly killed. But Iam in- 
clined to believe that he rests this 
assertion upon some general princi- 
ple, which he thinks established, 
and not upon particular facts; for 
he gives none in proof of it, and I 
have often held a nerve of an animal 
newly killed in one hand, while 
with the other I touched the muscle 
to which the nerve belonged, but 
never saw contractions by this 
means excited. Lhave also frequent- 
ly taken hold of a nerve of an ani- 
mal, which was recently killed, with 
a non-conductor of electricity, and 
have in this way applied its loose 
end to the external surface of the 
muscle which it entered, without 
ever observing motion to follow. I 
think, therefore, I am entitled to 
conclude, not only that the theor 
advanced by Mr. Galvani, respect- 
ing the cause of the muscular mo- 
tions in his experiments, is erro. 
neous; but also, that the influence, 
whatever its nature may be, by 
which they are excited, does not 
exist in a disengaged state in the 
muscles and nerves, previously tothe 
application of metals. Should it be 
urged 
