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GALVANISM ***




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AN ACCOUNT
OF
_THE LATE IMPROVEMENTS_
IN
GALVANISM,
WITH A SERIES OF CURIOUS AND INTERESTING
_EXPERIMENTS_
PERFORMED
BEFORE THE COMMISSIONERS OF THE FRENCH NATIONAL INSTITUTE,
AND REPEATED LATELY IN THE
ANATOMICAL THEATRES OF LONDON.

BY JOHN ALDINI,
PROFESSOR OF EXPERIMENTAL PHILOSOPHY IN THE UNIVERSITY OF BOLOGNA,
MEMBER OF THE MEDICAL AND GALVANIC SOCIETIES OF PARIS, OF THE
MEDICAL SOCIETY OF LONDON, ETC.

TO WHICH IS ADDED,
AN APPENDIX,
CONTAINING THE AUTHOR’S EXPERIMENTS
ON THE BODY OF A MALEFACTOR EXECUTED AT NEWGATE.
_&c. &c._

_ILLUSTRATED WITH ENGRAVINGS._

[Illustration: Medallions]

_LONDON_:
PRINTED FOR CUTHELL AND MARTIN, MIDDLE-ROW, HOLBORN,
AND J. MURRAY, NO. 32, FLEET-STREET,
BY WILKS AND TAYLOR, CHANCERY-LANE.
1803.




EDITOR’S PREFACE.


Few discoveries in modern times have excited so much curiosity as that
of Galvanism. Ever since it was first made known by its celebrated
Author, it has engaged the attention of the most eminent philosophers
in Europe; and various researches have been undertaken to ascertain
the principles on which it depends; and the laws to which it is
subject.

Though some of its singular properties are fully established, it must
be allowed that the discovery is still in its infancy; but enough of
it is known to prove its importance, and to induce philosophers to
continue their researches, which there is every reason to suppose may
lead to some very curious results.

The experiments, indeed, which have already been made, seem to
indicate that it may open a new field in the healing art; and it
appears by a late report presented to the Class of the Exact Sciences
of the Academy of Turin, that the medical application of it has been
attended with the most beneficial effects in a case of confirmed
hydrophobia.

While Galvanism, independently of other advantages, holds out such
hopes of utility in regard to objects so interesting to mankind; a
work containing a full account of the late improvements which have
been made in it, illustrated by a complete course of experiments,
cannot fail of being acceptable to the public in general, and in
particular to medical men, to whose department, in one point of view,
it more essentially belongs.

When Professor Aldini left this country, the manuscript, written in
French, together with two printed Latin Dissertations, was put into
the Editor’s hands, in order that they might be prepared for the
press. A translation of these forms the principal part of the work:
and an Appendix has been added, containing the author’s experiments on
the body of a malefactor executed at Newgate; experiments of a similar
kind on the bodies of three criminals decapitated at Bologna; and an
experiment lately made at Calais, which seems to show that Galvanism
is susceptible of being conveyed to a very considerable distance
through the water of the sea.

The Editor thinks it necessary to observe, that the principal
experiments, of which an account is given in this work, are
illustrated by proper engravings, and that the title page is
embellished with a representation of the gold medal presented to the
Author, as a mark of their respect, by the medical professors and
pupils of Guy’s and St. Thomas’s Hospitals.

LONDON,
_May 12th, 1803_.




CONTENTS.


PART I.

PAGE

OF THE NATURE AND GENERAL PROPERTIES OF GALVANISM.

PROPOSITION I. _Muscular contractions are excited by the
development of a fluid in the animal machine, which is
conducted from the nerves to the muscles without the
concurrence or action of metals_ 3

PROP. II. _The Galvanism excited, in the preceding experiments,
is not owing to the communication nor to the transfusion of
the general electricity, but to an electricity peculiar to
animals, which acts a very distinguished part in the animal
economy_ 6

PROP. III. _Galvanism develops itself in a powerful manner,
independently of metals, by means of the human animal machine_ 8

PROP. IV. _Muscular contractions can be excited, under certain
conditions, without establishing a continued arc from the
nerves to the muscles_ 11

PROP. V. _The effects of Galvanism, in the preceding
experiments, do not depend on the action of any stimulant,
which occurs in performing the experiments, and ought not to
be confounded with the effects of that action_ 12

PROP. VI. _Galvanism is excited in the animal machine without
any intermediate body, and merely by the application of the
nerves to the muscles_ 14

PROP. VII. _The heterogeneity of metals contributes, in a great
degree, to excite muscular contractions with more facility,
but is not absolutely necessary to their production_ 19

PROP. VIII. _The Leyden flask, the Voltaic pile, and animal
substances, have the faculty of absorbing principles from the
atmospheric air in an insulated plenum_ 21

PROP. IX. Flame _prevents the action of the Leyden flask, as
well as that of the pile, and also muscular contractions_ 27

PROP. X. _Certain fluids, applied to the whole surface of the
pile, or of animal parts, do not prevent the action of
Galvanism_ 29

PROP. XI. _Mere electrization, by means of the common kinds of
apparatus, does not increase the action of Galvanism_ 32

PROP. XII. _The Galvanic action is increased by employing as
part of the arc the apparatus of Volta, or the electrified
Leyden flask_ 34

PROP. XIII. _Galvanism, in animals and in the pile, traverses
large spaces with the same rapidity as the electric fluid_ 36

PROP. XIV. _The muscular contractions, which, according to the
observations of Galvani, are produced by an electric
atmosphere whether natural or artificial, correspond entirely
with those produced by the pile, or by similar kinds of
apparatus_ 37

PROP. XV. _Opium, cinchona, and other stimulants of a similar
kind, which exercise a powerful action on the animal machine,
contribute also to excite the action of the pile_ 41

PROP. XVI. _If the general relation between Galvanism and
electricity be examined, such a correspondence will be found
between them, as tends to confirm the analogy already stated_ 44

PROP. XVII. _The hypothesis of an animal pile, analogous to
that formed artificially, seems well calculated to explain
the sensations and contractions in the animal machine_ 47


PART THE SECOND.

ON THE INFLUENCE WHICH GALVANISM HAS ON THE VITAL POWERS 53

SECTION I. _Galvanism applied to various quadrupeds, birds, and
other warm-blooded animals_ 54

SECTION II. _Experiments made on human bodies after death_ 67


PART THE THIRD.

ON THE POWER OF GALVANISM AS APPLIED TO MEDICINE 97

SECT. I. _Advantages which the medical administration of
Galvanism has over that of common electricity_ 99

SECT. II. _Application of Galvanism to the organs of hearing
and of sight_ 101

SECT. III. _Application of Galvanism in cases of asphyxia and
drowning_ 110

SECT. IV. _Galvanism applied to the cure of melancholy madness_
113

SECT. V. _General reflections on the action and influence which
Galvanism, considered in a medical point of view, exercises
on the animal œconomy_ 123

DISSERTATION _on animal electricity, read in the Institute of
Bologna in the year 1793_ 133

SECOND DISSERTATION _on animal electricity, read in the
Institute of Bologna in the year 1794_ 155

_Conclusion_ 186


APPENDIX 189

No. I. _An account of the experiments performed, by J. Aldini,
on the body of a malefactor executed at Newgate Jan. 17,
1803_ ib.

No. II. _Report presented to the Class of the Exact Sciences of
the Academy of Turin, 15th August 1802, in regard to the
Galvanic experiments made by_ C. VASSALI-EANDI, GIULIO, _and_
ROSSI, _on the 10th and 14th of the same month, on the bodies
of three men a short time after their decapitation_. _By_ C.
GIULIO 204

No. III. _Account of an experiment made at Calais, on the
transmission of Galvanism through an arm of the sea_ 217




AN ACCOUNT

OF THE LATE

IMPROVEMENTS IN GALVANISM.


A just tribute of applause has been bestowed on the celebrated
Professor Volta for his late discovery; and I have no desire to
deprive him of any part of that honour to which he is so justly
entitled; but I am far from entertaining an idea that we ought, on
this account, to neglect the first labours of Galvani. Though these
two philosophers pursued different routes, they concurred to throw
considerable light on the same points of science; and the question now
is, to determine which of them deduced the most just consequences from
the facts he observed; and then to ascertain whether the facts
established by Galvani lead to the theory of Volta, or whether those
discovered by Volta are connected with the theory of Galvani. For my
part, I am of opinion that these two theories may serve in an eminent
degree to illustrate each other.

Last year Professor Volta announced to the public the action of the
metallic pile. I here propose to exhibit, according to the principles
of Professor Galvani, the action of the animal pile.

Such is the plan I have conceived in order to reconcile the systems of
these two illustrious philosophers: it forms the object of the present
work, which is divided into three parts. In the first I shall exhibit
the action of Galvanism independently of metals, and explain some of
its general properties. The second will contain experiments on the
power of Galvanism to excite the vital forces. In the third I shall
propose some useful applications of it to medicine, and explain the
principles on which the new medical administration of Galvanism is
founded. To render the work as methodical as possible, I have
endeavoured to arrange the experiments in such a manner that they may
serve as proofs to a series of general propositions, which, it is
hoped, will be of use to physiology and to the doctrine of the animal
economy.




PART THE FIRST.

OF THE NATURE AND GENERAL PROPERTIES OF GALVANISM.




PROPOSITION I.


_Muscular contractions are excited by the development of a fluid in
the animal machine, which is conducted from the nerves to the muscles
without the concurrence or action of metals._


EXPERIMENT I.

Having provided the head of an ox, recently killed, I thrust a finger
of one of my hands, moistened with salt water, into one of the ears
(Plate I. fig. 1.), at the same time that I held a prepared frog in
the other hand, in such a manner that its spinal marrow touched the
upper part of the tongue. When this arrangement was made, strong
convulsions were observed in the frog; but on separating the arc all
the contractions ceased.

This experiment will succeed still better if the arc be conveyed from
the tongue of the ox to the spinal marrow of the frog. This method was
found to be exceedingly convenient for trying the effect of Galvanism
on several calves.


EXPERIMENT II.

Having provided the trunk of a calf, I conveyed the arc from the
muscles of the abdomen to the spinal marrow of a frog, prepared and
arranged in the usual manner. The frog seemed much affected, and the
contractions were exceedingly violent when the arc was composed of a
chain of different persons, united together by the hands moistened
with salt water.


EXPERIMENT III.

I connected, by means of one chain of moisture, the heads of two or
three calves, and observed that by this combination the force of the
Galvanism was exerted with more energy: a frog, which was not affected
by touching one head, experienced violent contractions when applied to
a series of several heads connected together.


EXPERIMENT IV.

I think it proper here to mention a very curious observation which I
made lately at Paris, in company with professor Huzzard, and in the
presence of the Commissioners of the National Institute. On applying
the spinal marrow of a prepared frog to the cervical muscles of a
horse’s head, separated from the body, no muscular convulsions took
place; but if, at the same time, another person touched with his hand,
moistened by a solution of muriate of soda, the spinal marrow of the
horse, convulsions were always produced in the frog, though there was
no communication between the persons, except that formed by a floor on
which they stood.




PROPOSITION II.


_The Galvanism excited, in the preceding experiments, is not owing to
the communication nor to the transfusion of the general electricity,
but to an electricity peculiar to animals, which acts a very
distinguished part in the animal economy._


EXPERIMENT I.

Having placed the trunk of a calf (Plate I. fig. 2.) on an insulated
table, I made a longitudinal incision in the breast, in order to
obtain a long series of muscles uncovered. I then arranged two
insulated persons in such a manner that the one with a finger,
moistened by salt water, touched the spinal marrow of the calf, while
the other applied the spinal marrow of a frog to the muscles of the
trunk. Every time this arc was formed, muscular contractions were
produced in the frog. When the two persons let go each other’s hands,
the contractions ceased. I repeated this experiment, with the same
success, on the insulated head of an ox, conveying the arc from the
spinal marrow of the frog to the tongue. Frogs were as violently
affected when the experiment was made with the insulated trunks of
different kinds of birds.

This experiment, in my opinion, affords a decisive proof that the
Galvanic fluid is peculiar to the animal machine, independently of the
influence of metals, or of any other foreign cause. In these
experiments, indeed, we have some animal machines, so combined that
the result is strong contractions in the frog. All the bodies were
insulated; and, therefore, it cannot be supposed that the contractions
were occasioned by the direct influence of that general principle,
which pervades every body in nature. Hence it is evident, whether it
be ascribed to the action of the animal chain, formed by the arms of
the persons, or to the animal pile, formed by the trunk of the calf,
that we shall still be obliged to acknowledge the action of a
principle which belongs to the organization of the animal machine,
without having any dependence on metals.

* * * * *

To prove in the animal body the existence of a principle which
philosophers can by certain means excite and direct at pleasure in
their experiments, is a matter of the greatest importance; though the
manner in which it is put in action by nature, however wonderful, is
unknown to us. Here then we have developed a very energetic fluid,
capable of transmission, and deriving its origin from the action of
the animal forces; since the parts of bodies separated from the common
reservoir of general electricity have still of themselves the faculty
of reproducing it, and of causing it to circulate in a manner proper
for exciting muscular contractions.




PROPOSITION III.


_Galvanism develops itself in a powerful manner, independently of
metals, by means of the human animal machine._


EXPERIMENT I.

If you hold in your hand, moistened with salt water, the muscles of a
prepared frog, and apply the crural nerves to the tip of your tongue,
you will immediately see violent contractions produced in the frog.
All suspicion of any stimulant exerting an action in this case, may be
removed by repeating the experiment with the frog held in the dry
hand: the muscular contractions will then cease, unless the action of
Galvanism in the frog, or in the animal machine, be uncommonly
powerful; in which case contractions may be produced without
establishing an arc from the nerves to the muscles.


EXPERIMENT II.

I held the muscles of a prepared frog in one of my hands, moistened by
salt water, and brought a finger of the other hand, well moistened,
near to the crural nerves. When the frog possessed a great deal of
vitality the crural nerves gradually approached my hand, and strong
contractions took place at the point of contact. This experiment
proves the existence of a very remarkable kind of attraction, observed
not only by myself, but also by those whom I requested to repeat the
experiment.


EXPERIMENT III.

The above experiment requires great precision in the preparation, and
a considerable degree of vital power in the frog. I have been informed
by Professor Fontana, in a letter lately received from him, that this
phænomenon depends on very delicate circumstances, which he proposes
to explain. He assures me, at the same time, that he has twice seen
the nerve attracted, in this manner, by the muscle. Being desirous to
render this phænomenon more evident, I formed the arc, by applying one
of my hands to the spinal marrow of a warm-blooded animal, while I
held a frog in the other, in such a manner that the crural nerves were
brought very near to the abdominal muscles. By this arrangement the
attraction of the nerves of the frog became very sensible. I performed
this experiment for the first time, at Oxford, before Sir Christopher
Pegge and Dr. Bancroft, and repeated it in the anatomical theatres of
St. Thomas’s and Guy’s hospitals.


EXPERIMENT IV.

I made the same observations on the body of a man as I had before made
on the head and trunk of an ox. Having obtained the body of an
executed criminal, I formed an arc from the spinal marrow to the
muscles, a prepared frog being placed between, and always obtained
strong contractions without the aid of the pile, and without the least
influence from metals. I obtained the same result, in a certain
degree, from the bodies of men who had died a natural death.


EXPERIMENT V.

Let four or more persons hold each other by the hands, moistened by a
solution of muriate of soda, so as to form a long animal chain. If the
first hold in his hand the muscles of a prepared frog; and if the
last, at the other end of the chain, touch the spinal marrow or the
crural nerves, contractions will be produced: if the animal chain be
broken, the contractions will immediately cease. I performed this
experiment, making the animal chain to consist of two persons, before
the Galvanic Society at Paris, and in Mr. Wilson’s anatomical theatre,
Windmill-street.




PROPOSITION IV.


_Muscular contractions can be excited, under certain conditions,
without establishing a continued arc from the nerves to the muscles._


EXPERIMENT.

Having obtained the body of an executed criminal, I caused the biceps
muscle to be laid bare, and brought near to it the spinal marrow of a
prepared frog. By these means contractions were produced in it much
stronger than I had ever obtained in warm-blooded animals. I repeated
the experiment, being myself insulated, and observed no signs of
contraction. The same phænomena were exhibited with the head of an ox,
which possessed an extraordinary degree of vitality.




PROPOSITION V.


_The effects of Galvanism, in the preceding experiments, do not depend
on the action of any stimulant, which occurs in performing the
experiments, and ought not to be confounded with the effects of that
action._


EXPERIMENT I.

In the experiment of the frog applied to the uncovered biceps muscle
of the body of the malefactor, if any other body be made to touch the
frog it will remain motionless. This proves that the contractions
produced in the frog do not arise from the impulse of the mere contact
of the spinal marrow with the muscle of the human animal machine.


EXPERIMENT II.

To remove still further all suspicion of the action of stimulants, in
the preceding experiments, I prepared two frogs, and connected the
extremities of one with the spinal marrow of the other. I then held in
my hand the extremities of one of the frogs, and applied the spinal
marrow of the other to the uncovered muscles of the head of an ox,
which possessed a great degree of vitality. By these means
contractions were produced in both the frogs. It is evident, in this
experiment, that the force of the stimulant, if there were any, might
act on the second frog, but not on the first.




PROPOSITION VI.

_Galvanism is excited in the animal machine without any intermediate
body, and merely by the application of the nerves to the muscles._


Several philosophers have endeavoured to obtain this interesting
result. Professor Volta, in a letter which he addressed to me, in
Brugnatelli’s Journal, observed, “that various parts of animals can
excite Galvanism, independently of metals.” Galvani, a short time
before his death, proposed two ingenious methods of obtaining this
result, and gave me a description of them. This, however, has not been
able to destroy the incredulity of some philosophers, who hitherto
have confounded Galvanism with metallic electricity, under an idea
that all contractions proceed from irritation, produced by the action
of metals. For this reason I have, with confidence, announced my
method, which enables any one to observe this important result.


EXPERIMENT I.

Having prepared a frog in the usual manner, I hold the spinal marrow
in one hand (Plate I. fig. 3.), and with the other form an angle with
the leg and foot, in such a manner that the muscles of the leg touch
the crural nerves. On this contact strong contractions, forming a real
electrico-animal alarum (_carillon_), which continue longer or shorter
according to the degree of vitality, are produced in the extremity
left to itself. In this experiment, as well as in the following, it is
necessary that the frogs should be strong and full of vitality, and
that the muscles should not be overcharged with blood.


EXPERIMENT II.

By observing the directions already given, very strong convulsions
will be obtained; but they must not be ascribed to the impulse
produced by bringing the nerve into contact with the muscle. If the
experiment be repeated, covering the muscle, at the place of contact,
with a non-conducting substance, the contractions will entirely cease;
but they will be re-produced as soon as the nerve is made to touch the
muscular substance. In performing this experiment, in public, I
obtained several times more than two hundred successive contractions;
but this was never the case when I formed the same contact with the
muscle by means of a conducting substance, and even with a plate of
metal.

To ensure the success of this interesting experiment, the nerves must
be prepared as speedily as possible, by disengaging them from every
foreign substance. It will be proper also to apply the nerves not to
one but to several points of the muscle, throughout its whole length.
It is observed, that the contact of the nerves with the tendinous
parts which communicate with the muscles, often serves to increase the
muscular contractions. I performed the above experiment before several
able professors, among whom were the celebrated Brugnatelli and
Carcano, who, with that modesty peculiar to them, made several
ingenious observations on the precision which might be given to it.
Professor Brugnatelli was apprehensive that, as I had accidentally


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