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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
touched some metals before I performed the experiment, metallic
particles might have adhered to my fingers, and thus have served, in
some measure, as invisible arming, sufficient of itself to excite
muscular contractions. This suspicion, however, I removed, by
immersing my hands in water, to detach every foreign substance. He
then observed that animal moisture, independently of the circulation
of the Galvanic fluid from the nerves to the muscles, might also
excite muscular contractions; and he requested that the crural nerves
might be washed in common water. This was accordingly done; and the
humidity of the nerves being thus externally removed, very strong
contractions were still produced, as the professor found, to his full
conviction, on repeating the experiment himself several times[1].
[1] It may not be improper here to observe, that my
method of exciting muscular contractions, without
metals, is very different from that proposed by others.
I do not know that convulsions have ever been obtained
in cold-blooded animals by means of warm-blooded. From
observations I have made, I flatter myself with the
hope of being able to obtain contractions without
metals, even in the muscles of warm-blooded-animals.
But to ensure the certainty of this method would
require long practice, and a preparation attended with
considerable difficulty. I however propose to attempt
it on my return to Italy. Some philosophers, indeed,
had conceived the idea of producing contractions in a
frog without metals; and ingenious methods proposed by
my uncle Galvani induced me to pay attention to the
subject, in order that I might attain to greater
simplicity. He made me sensible of the importance of
the experiment, and therefore I was long ago inspired
with a desire of discovering that interesting process.
It will be seen in the _Opuscoli of Milan_, that I
shewed publicly, to the Institute of Bologna,
contractions in a frog without the aid of metals, so
far back as the year 1794. The experiment, as described
in a memoir addressed to M. Amorotti, is as follows: “I
immersed a prepared frog in a strong solution of
muriate of soda. I then took it from the solution, and,
holding one extremity of it in my hand, I suffered the
other to hang freely down. While in this situation, I
raised up the nerves with a small glass rod, in such a
manner that they did not touch the muscles. I then
suddenly removed the glass rod, and every time that the
spinal marrow and nerves touched the muscular parts,
contractions were excited. Any idea of a stimulus
arising either from the action of the salt, or from the
impulse produced by the fall of the nerves, may be
easily removed. Nothing will be necessary but to apply
the same nerves to the muscles of another prepared
frog, not in a Galvanic circle; for, in this case,
neither the salt, nor the impulse even if more violent,
will produce muscular motion.
EXPERIMENT III.
The Commissioners of the French National Institute remarked, that, in
order to give the greatest precision possible to these experiments, it
would be necessary to insulate entirely the nervous and muscular
systems. For this purpose, I applied these parts to each other by
means of glass rods, and each time they were brought into contact I
obtained muscular contractions. The case was the same when an animal
arc was applied to two insulated frogs: contractions were produced in
them both. The apparatus employed for this purpose may be seen in
Plate I. fig. 5 and 6.
EXPERIMENT IV.
Having prepared a frog according to the usual method, I cut one of its
crural nerves in such a manner that the trunk was united to the spinal
marrow by means of the other nerve, which remained uncut, and also by
a blood-vessel contiguous and parallel to the cut nerve. I then
repeated the above experiment; and, though only one nerve was in
contact with the muscles, I obtained the same results.
EXPERIMENT V.
A ligature was placed loosely around the middle of the crural nerves,
and one of these nerves at the ligature applied to the corresponding
muscles: strong contractions ensued; which, however, did not take
place, when the ligature was drawn tight, at the insertion of the
nerves into the muscles of the thigh.
PROPOSITION 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._
This proposition I could demonstrate in a direct manner, by means of
experiments, which I published formerly, on the contractions excited
by very pure mercury, and which were repeated, in different ways, by
the celebrated Humboldt. I am, however, happy to have an opportunity
of examining the influence of arming with heterogeneous substances;
and I shall endeavour to prove that it cannot, of itself, produce the
effect of muscular contractions.
EXPERIMENT I.
If several prepared frogs, ten or more for example, be placed on a
table (Plate I. fig. 7.), and arranged parallel to each other, in such
a manner that the whole system of the nerves shall be at one end, and
that of the muscles at the other,—on applying two armatures and a
metallic arc to the first of these frogs, muscular convulsions will be
immediately excited, not only in the first frog, but in all the rest.
EXPERIMENT II.
If the experiment be repeated with the frogs arranged in such a manner
that the spinal marrow and muscles are not each at one end (Plate I.
fig. 8.), but disposed alternately so that the spinal marrow of one
touches sometimes the muscles of another, or vice versa, convulsions
will then be produced only in some of the frogs, and not in the whole
series. This experiment proves that the effect does not, in any
manner, depend on the action of metals; because metallic electricity
in the first experiment ought to exercise an action only on the first
frog, and not on the rest; and, in the second, ought to cause them all
to move together, or to leave them motionless.
I shall now proceed to those experiments which appear to be best
calculated to support the opinion of the great analogy between
electricity and Galvanism.
PROPOSITION VIII.
_The Leyden flask, the Voltaic pile, and animal substances, have the
faculty of absorbing principles from the atmospheric air in an
insulated plenum._
EXPERIMENT I.
By means of a metallic point, I electrified the interior side of a
glass jar, which I inverted and placed on a plate of metal, so as to
form an insulated plenum. In a little time, I saw the water rise in
the glass several lines; and I then flattered myself with the hopes of
obtaining some remarkable effects by another method.
EXPERIMENT II.
I provided for this experiment a Leyden flask, seven inches in height
and about three in diameter, coated in the usual manner with tin foil:
the exterior end of the wire terminated in a sharp point, so that the
electric fluid which escaped from it could easily combine with the
principles of the atmospheric air, with which it had a greater
affinity. I then electrified the jar, and covered it with a glass
receiver of such a size that its electricity could not be weakened by
the sides of the latter. I thus formed an insulated plenum, and at the
end of half an hour I saw the water ascend in the receiver in a very
sensible manner.
EXPERIMENT III.
Having made the wire to terminate, not in a point, but in a metallic
knob, as usual, I again charged the jar, and having placed it under a
common receiver, at the end of about half an hour I found that the
elevation of the water was much greater. To remove every suspicion
that this might arise from the water employed in the preceding
experiment, to insulate the plenum, I substituted mercury in its
stead; and though the elevations were less, they were, however,
analogous to those which had been observed a little before with water.
By repeating this experiment with a similar jar, not electrified, one
may be easily convinced, that the elevation of the water in the bell
ought not to be ascribed to a difference in the temperature of the air
within it.
EXPERIMENT IV.
I placed under a bell-glass, forming an insulated plenum, a pile
consisting of fifty plates of silver and zinc. Next morning I observed
that the water had risen some inches, indicating that a great
absorption of air had taken place. Having then introduced a taper into
the receiver, it was immediately extinguished. The pile, without being
arranged anew, was placed under the same receiver; and on forming an
insulated plenum, I observed, after twenty-four hours had elapsed, a
sensible absorption of air. A taper was then introduced, and I
obtained the same result. I replaced the pile under the receiver, and
found, on the third and following days, that the pile retained its
moisture, so that till the tenth day it gave analogous results. I
repeated the same experiment with oxygen gas, and found, six days
after, that the water in the bell had risen a foot.
EXPERIMENT V.
The same results may be obtained without employing large piles and
large receivers. In general, it will be sufficient to arrange, in
alternate strata, some plates of heterogeneous metals. If two plates
of copper and zinc be placed under a bell an inch and a half in
diameter, and three inches in height, and if an insulated plenum be
then formed, two days after the water will have risen about half an
inch. Having repeated the experiment with different metals, I found
that a greater or less absorption of air had taken place, according to
the difference of their nature and combination. This inspired me with
the idea of making a series of experiments with different metals; and
I hope to be able, at some future period, to form a table of the
different heights of the fluid, which may serve to determine how far
they are respectively susceptible of oxidation. However, to ascertain
the oxidation of metals with precision, pieces of coin mixed with
alloy ought not to be employed. Pure metals, formed into small piles,
must be subjected to observation, and ought to be placed under equal
bells, at the same temperature as that of the atmosphere. Until it be
proved that the absorption of oxygen in the above experiments is
merely a chemical effect, altogether unconnected with the action of
Galvanism, I think I may be allowed to avail myself of it to prove the
proposed analogy.
EXPERIMENT VI.
The ingenious theory of Girtanner, who ascribes the cause of muscular
contractions to oxygen, the curious experiments by which Professor
Humboldt revives the muscular force, by means of oxygenated muriatic
acid, and those made by the celebrated Fourcroy on the same subject,
induced me to examine the effect resulting from a combination of
oxygen with muscular fibres, in a state of the greatest vitality. For
this purpose, I adapted to a bell-glass a bent metallic wire, from
which were suspended fourteen frogs, prepared with the utmost
dispatch, and almost at the same instant, by myself and several of my
pupils; and having formed an insulated plenum, I found, at the end of
twenty-four hours, that the water had risen in the bell to the height
of about half an inch.
EXPERIMENT VII.
I repeated this experiment, with the same success, on warm-blooded
animals. I provided, for that purpose, the extremities of different
pullets from which the crural nerves had been previously separated,
and found that the elevations of the water, in the insulated plenum,
were much less when I employed the fibres of these animals after their
vitality had been weakened.
EXPERIMENT VIII.
Having obtained the bodies of some executed criminals, I exposed to
the action of an insulated plenum the nervous and muscular fibres, and
the substance of the brain. The elevations of the water were
remarkable, in consequence of the different substances subjected to
experiment, which, according to their different characters, exercised
a different action on the oxygen. This fact ought to induce
physiologists to undertake experiments of a similar kind with other
gases, to enable them to determine the strength of the affinity
exerted by animal substances to combine with oxygen.
EXPERIMENT IX.
As fishes, and in particular the torpedo, furnish a large quantity of
animal or Galvanic electricity, I was inclined to think they would
exhibit the before-mentioned effects in a very striking manner in an
insulated plenum. I mentioned to Professor Mojon of Genoa the
experiment I proposed to make; and, in a letter which I lately
received from him, he informed me of the result, as follows:
“I took a strong torpedo, and, as soon as it was dead, armed
its nerves with the usual armature. Having then placed it on
an insulating stool, a little elevated above water, I
covered it with a bell-glass the content of which was equal
to 432 cubic inches. At the end of some hours I observed,
with great surprise, that the water under the insulated
plenum began to rise progressively during about ten hours;
and at the end of forty-eight I found that it had risen an
inch; so that it occupied a ninth part of the capacity of
the bell, that is to say, forty-eight cubic inches. I
analysed the remaining air, and found that the bell
contained no more than 80 cubic inches of oxygen gas, and
324 of azotic gas; and that, during the above period, more
than two-fifths of the oxygen gas contained in the bell had
been absorbed.”
I propose going to the sea-coast, in order that I may repeat the
experiment on the torpedo without any armature; and I shall embrace
that opportunity of making various researches in regard to the new
theory of Galvanism. I think it necessary, in general, to submit to
new experiments the different animal parts immersed in the different
aëriform fluids, fixing their various combinations according to the
degrees of Galvanic force which they may possess.
PROPOSITION IX.
_Flame prevents the action of the Leyden flask, as well as that of the
pile, and also muscular contractions._
EXPERIMENT I.
I placed a lighted taper on an insulating stool; and having made the
wire, proceeding from the interior coating of a charged Leyden flask,
to pass through the flame, I found that, without forming an arc, it
lost a portion of its electricity. If the experiment be repeated in
such a manner that the flame makes a part of the arc between the two
coatings, the flask is entirely discharged, without the arms of the
person who forms part of the arc experiencing the least shock.
EXPERIMENT II.
I adapted to the summit of the pile a circular brass vessel,
containing spirit of wine. By these means the pile was made to
terminate in a strong flame, to which I applied a metallic conductor,
while with the other hand I touched the bottom of the pile. The
Galvanic fluid still withstood my efforts; and the case was the same
when I substituted for the spirit of wine the flame of a common
candle. It is proper here to remark, that the flame did not lessen the
action of the Galvanism when the conductor, instead of being applied
to the flame, was applied to the plate at the summit of the pile.
EXPERIMENT III.
I have already proved by a series of experiments, addressed to C.
Lacepede, that flame made to form part of the arc applied to the
nerves and muscles of a frog, prevents muscular contractions. I
repeated the experiment, with the same result, on several warm-blooded
animals. I observed that the flame interposed in the arc, which
touched the back and belly of the torpedo, prevented the electric
shocks.
PROPOSITION X.
_Certain fluids, applied to the whole surface of the pile, or of
animal parts, do not prevent the action of Galvanism._
EXPERIMENT I.
Two years ago, I made various experiments on this subject at Florence,
with the celebrated Fontana; and we found that a pile, composed of a
hundred plates of zinc and silver, after being immersed some time in
common water, still exercised a very strong action. Professor Fontana
informs me, in a letter, that he has performed the same experiment
several ways, and always with the same success.
EXPERIMENT II.
Being desirous to examine the nature of the element inhabited by the
numerous family of fishes, which are also subject to the influence of
the Galvanic processes, I filled with sea-water thirty earthen
vessels; and having formed a communication between them, by means of
heterogeneous arcs, composed of brass and zinc, I obtained a shock,
which appeared to me stronger than that obtained with artificial salt
water. By establishing an arc with only five of these vessels, the
action was very sensible. A pile composed of pieces of pasteboard,
moistened with sea-water, and entirely immersed in the same water,
gave, when tried, very strong shocks.
EXPERIMENT III.
I was able to prove the action of the Galvanic pile and of metals
under water, by the following simple experiment: I placed a plate of
zinc at the bottom of a vessel filled with salt water, (Plate II. fig.
6.). A person then brought the spinal marrow of a frog into contact
with the surface of the salt water; and another person, absolutely
insulated, touched with a silvered copper wire the plate of zinc.
Every time that the wire was brought into contact with the zinc,
muscular contractions took place. I am well aware, that the advocates
for metallic electricity will deduce from the plain statement of this
fact, an induction contrary to Galvanism; but my candour, on this
occasion, will show how much I am attached to the cause of truth.
EXPERIMENT IV.
Among animal bodies, the torpedo is one of those which produce the
most powerful Galvanic action. In the autumn of 1801, I made some
experiments on this animal at Genoa, in conjunction with Professor
Mojon and his brother, who gave me every assistance in their power.
When I touched the torpedo, under water, at the moment when it gave
the shock, it contracted itself, and two jets of water proceeded from
the two holes in its head. To obtain the shock, it was not necessary
to touch two distinct parts of its body: in many cases, the
application of the hand to the electric organ was sufficient.
PROPOSITION XI.
_Mere electrization, by means of the common kinds of apparatus, does
not increase the action of Galvanism._
EXPERIMENT I.
Artificial electricity was communicated to an apparatus, composed of a
hundred cups, care being first taken to insulate the table and the
persons who were afterwards to receive the action of it. If we suppose
that the heterogeneous arcs were charged with different kinds of
electricity, it would seem that, by communicating to them any
electricity, the electricity of the whole apparatus ought to have been
reduced to the same kind; consequently that no shock ought to have
been produced. The contrary, however, was the case. We experienced
very strong shocks, very little different from those which would have
been obtained without artificial electricity. I observed the same
result with the pile.
EXPERIMENT II.
An insulated torpedo being electrified, the shocks it gave were not
increased. The torpedo was killed, and then armed, according to the
method of Galvani, for the purpose of trying whether metallic
electricity, in this case, would have any influence over it. After
this arrangement was made, every time that the conducting arc was
applied to it strong contractions were produced; but very little
different from those remarked in other animals. This observation is
agreeable to those made at Naples by the celebrated Abilgaard, who,
having subjected the torpedo to the Galvanic processes, found no
extraordinary contractions.
PROPOSITION XII.
_The Galvanic action is increased by employing as part of the arc the
apparatus of Volta, or the electrified Leyden flask._
EXPERIMENT I.
In the hall of the Institute, I placed on a large table a hundred
glass cups, and arranged them in such a manner as to form two
rectangles, each composed of fifty. I established a communication
between the first of these cups and the apparatus of Volta, by means
of a metallic wire, which proceeded from one of the interior chambers
of the _Cabinet de Physique_, and terminated at the place where the
experiment was performed. I then tried this arrangement several times;
and, however different opinions might be in regard to the precise
increase of the action of the Galvanism, all constantly agreed in
considering the shock as stronger. Some even went so far as to assert
that it was increased a third.
It gave me great satisfaction to be able, on this occasion, to confirm
the last discovery of Professor Volta, as well as one of those which
he had made before. One observation, well attested, which tends to
establish the truth of this proposition, is, that if a person touch
the summit and base of the pile with two large metallic conductors,
the shocks he receives will be much stronger.
EXPERIMENT II.
Electricity, concentrated in the Leyden flask, contributes also to
increase the action of Galvanism. Having prepared a pile, composed of
fifty plates of copper and zinc, I formed an arc by interposing a
charged jar, and obtained an explosion much stronger than that
obtained by the Leyden flask charged with an equal quantity of the
electric fluid, and discharged independently of the pile.
EXPERIMENT III.
I took the same flask, after it was discharged, and having formed a
portion of an arc, applied to the two extremities of the pile, I
observed that the Galvanism refused to pass the obstacle presented to
it by the stratum of glass interposed between the two coatings;
consequently I received no shock.
EXPERIMENT IV.
I repeated the second experiment, insulating the pile, and at the same
time the person who touched the pile with the charged flask. By these
means I obtained a much stronger explosion than could have been
produced separately by the Leyden flask or the pile. In this
experiment I observed that the repeated passage of the electricity of
the flask throughout the whole extent of the pile, did not deprive it
of the property of exciting Galvanism.
PROPOSITION XIII.
_Galvanism, in animals and in the pile, traverses large spaces with
the same rapidity as the electric fluid._
EXPERIMENT.
I extended an iron wire, two hundred and fifty feet in length, around
my chamber, taking great care that it should not any where touch
itself, and made its extremities to terminate at a table which I had
prepared for the experiment. One of these extremities being brought
into communication with a pile composed of fifty plates of copper and
zinc, I held the other in my left hand, and with my right touched the
summit of the pile. The Galvanism then proceeded from the bottom of
the pile to the summit, traversing a portion of the arc formed by the
animal machine. By the effect of this passage, we may therefore form
some opinion of the celerity of the Galvanic current. Its rapidity was
such, that neither I nor any of those who repeated the experiment
publicly, were able to determine the degree. The truth of this
proposition is confirmed by experiments lately made by the celebrated
Van Marum, who charged large batteries by means of Galvanism.
PROPOSITION 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._
When a change of equilibrium takes place in those systems of bodies
which communicate with the nerves and the muscles of the animal
machine, it is always sensible of this change, and muscular
contractions are produced.
EXPERIMENT I.
It is curious to see an animal, placed at the extremity of an
apartment, experience a shock, when the electric spark is extracted at
a considerable distance. I performed this experiment several times in
the _Cabinet de Physique_ of the Institute of Bologna, by means of a
metal wire, not insulated, which was at the distance of four feet from
the conductor of a common electrical machine. I repeated the
experiment with crural nerves, having a ligature in the middle; and on
extracting the spark, I observed violent contractions, which ceased
when the ligature was formed at the place of their insertion into the
muscles. I then performed with the new apparatus of Volta the
experiments which Galvani had made with artificial electricity alone.
At first I employed several glass cups and piles of from one to two
hundred plates of metal; which proved to me that similar results might
be obtained with the following simple apparatus.
EXPERIMENT II.
Having placed upon a table two glass vessels filled with salt water,
(Plate II. fig. 5.) which I connected by means of an arc composed of
brass and zinc, I applied to the surface of the water, in one of the
vessels, the spinal marrow of a prepared frog, the corresponding
muscles of which I held in one of my hands. Another person with his
hand, or a plate of metal, then touched the water contained in the
other vessel, and, at each contact, the muscles experienced violent
contractions. To remove all idea of the contractions being produced by
the action of the salt water, I connected with the spinal marrow a
part of the muscles of another animal, which, instead of the spinal
marrow, was made to touch the salt water, and obtained the same
result.
EXPERIMENT III.
The same apparatus being retained, if either the person who touches
the surface of the water in the first glass vessel, or the part of the
frog immersed in the second, be insulated, no muscular contractions
are produced; but they again take place when the insulation is
removed. The violence of the contractions is increased by increasing
the number of the glass vessels. If these vessels are made to
communicate by means of arcs, formed of one homogeneous metal, the
results are not different from those observed when heterogeneous
metals are employed.
EXPERIMENT IV.
Being desirous to confirm the theory of the Galvanic atmosphere, I
placed in it the body of an executed criminal. I removed the pile to
the distance of a foot from the trunk, without the usual communication
of metallic arcs; and having made an incision in each ancle, two
persons held two frogs prepared in the usual manner, in such a
position that the spinal marrow rested on the incisions. When matters
were thus arranged, every time that a third person touched the summit
of the pile, both the frogs experienced violent contractions, and to
such a degree, that, leaving free one of the extremities, a real
electrico-animal alarum was obtained, perfectly similar in its effect
and identity to that described by Galvani in his Commentary. When the
metallic apparatus is employed, if one of the persons who holds a frog
be insulated, the frog will remain motionless, while the other will
experience the usual effect. I had an opportunity of confirming the
truth of this observation, on the trunk of a dog, during a course of
experiments made in the _Hôpital de la Charité_, at Paris, and at St.
Thomas’s Hospital, London.
PROPOSITION 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._
EXPERIMENT I.
In the last sitting of the Institute of Bologna, at which I was
present, I constructed two piles, each composed of fifteen pieces of
silver and zinc, employing for the one an extract of opium, and for
the other an infusion of cinchona in alcohol. I covered the piles with
two equal receivers; formed an insulated plenum, by pouring mercury
around the bottoms of them; and placed weights on the receivers
sufficient to prevent the mercury from raising them. At the end of
some hours, I found a remarkable elevation of the surface of the
mercury, so that the receivers remained fixed without requiring any
weight to keep them down. In the bell which covered the pile where
extract of opium had been employed, the mercury rose more than an
inch; but in that covering the other, where cinchona had been used,
the elevation of the mercury was scarcely three lines.
EXPERIMENT II.
Having successively introduced a taper into each of the two receivers
before mentioned, it was immediately extinguished in that containing
the pile with the extract of opium; but in the other containing the
pile with the infusion of cinchona, it continued burning for some
time. I found also that four of the plates, at the bottom of the pile
where I employed opium, had suffered from the action of the mercury;
and that some others, to the height of about three inches and a half,
exhibited a few globules of that metal. The pile in which I employed
infusion of cinchona showed scarcely any signs of the action of the
mercury.
EXPERIMENT III.
As I concluded that the pile in which I had employed the alcoholic
extract of opium possessed more activity than the other, I examined it
for four or five days successively. I tried the flame of a taper with
the same result as before, and assured myself that this pile retained
the Galvanic power, though a little weakened, even till the eighth
day. On the other hand, twenty-four hours had scarcely elapsed, when
the pile in which alcohol and cinchona had been employed exhibited no
signs of activity.
EXPERIMENT IV.
I constructed two piles, in the same manner, with pieces of pasteboard
interposed, which had been previously moistened with strong solutions
of camphor and of castor oil, in pure alcohol. In these two piles the
Galvanic effects were much weaker in every respect than those observed
in the preceding experiment; for, besides the explosion being less,
the elevation of water in the insulated plenum was very small, and the
alteration of the flame was scarcely sensible.
EXPERIMENT V.
I was able to convince myself that the effects of the two piles,
before mentioned, were the immediate result of the substances
dissolved, and not of the alcohol; for, having constructed a pile of
thirty plates of silver and zinc, with pieces of pasteboard
interposed, moistened with pure alcohol, I observed no signs of
Galvanism; and the case was the same when I employed a pile of zinc
combined with copper and other metals.
PROPOSITION 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._
To illustrate this proposition, I shall here take a view of the
particular properties of electricity and Galvanism, which, if
considered separately, would not be sufficient for my object. I am,
however, of opinion, that when combined together they will serve to
prove it in a satisfactory manner.
1st, Galvanism, like artificial electricity, emits sparks, fuses
metals, and can even be employed to charge armed non-conducting
bodies. I have proved the last-mentioned property, discovered by the
celebrated Van Marum, with a new apparatus, composed of a pile with a
hole in the middle, in which I place the flask I intend to charge.
2dly, The influence of artificial electricity tends to accelerate the
putrefaction of animal parts; and the same phænomenon may be produced
by communication with the Voltaic pile, or by the first processes of
Galvani.
3dly, The electricity of the Leyden jar is renewed in part immediately
after its discharge. A similar phænomenon is exhibited by the pile;
and it is observed, if the common Galvanic armatures be employed, that
the vital force in animals is almost revived, when the arcs are
applied different times.
4thly, As the action of common electricity and of the pile is
suspended, when the combination of the metallic pieces is changed; in
like manner, in a system of several animal machines, if their
combination be changed, muscular contractions entirely cease.
5thly, Water may be decomposed by common electricity, as well as by
the Galvanic pile, according to the ingenious method proposed by Dr.
Wollaston. I lately saw, with the greatest pleasure, experiments on
this subject performed by himself with the utmost neatness and
precision. It is much to be wished, that the same result could be
obtained by animal Galvanism alone; as it might tend to throw great
light on some important points in physiology. For my part, I entertain
no doubt that, after repeated trials, it may one day be effected, by
means of large animals possessing a great abundance of animal
electricity.
To conclude: I think I may venture to assert, that the correspondence
between the properties of Galvanism and common electricity might be
carried to a much greater extent, in confirmation of the analogy which
I proposed to prove in this proposition.
PROPOSITION 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._
It seems to be proved by the observations of Mr. Davy, Professor in
the Royal Institution of Great Britain, and those of M. Gautherot at
Paris, that a pile may be composed without any metallic substances
whatever. We are therefore naturally led to suppose, that one may be
composed also of animal substances alone. Though this has never yet
been obtained by art, we behold it with admiration constructed by
nature in various animals. If we examine, indeed, the structure of the
regular bodies which succeed each other in the torpedo, the electrical
eel of Surinam, and in the silurus, we shall find them to be real
animal piles, differently arranged: and if an animal pile, exceedingly
strong, be capable of communicating a shock, why should not one of a
more moderate nature excite that activity which is necessary to
produce muscular convulsions? I have already proved, that the system
of the nerves and that of the muscles possess different Galvanic
powers, or, as it were, different kinds of electricity, to which the
animal moisture serves as a conductor. In this point of view, the
discovery of the pile of the celebrated Volta, instead of destroying
the principle of Galvanism, tends rather in a powerful manner to
support it. The object of Galvani’s system is to prove the existence
of an animal electricity, and then to explain how its action operates
in producing muscular sensations and contractions. The first part of
his system rests upon facts, the truth of which neither time, nor the
different experiments made by philosophers, have been able to weaken.
The second presents an hypothesis which, perhaps, may be further
illustrated when the physiology of the human body is better known.
Galvani, to explain the activity of animal electricity, supposes the
nerves and muscles to be like the Leyden jar; and this idea I
confidently adopted. But by the expression ‘Leyden flask’ he meant
nothing else than that in the animal machine there are two opposite
kinds of electricity, resulting from the nervous and the muscular
systems, to which animal moisture continually serves as a vehicle. It
was in this sense that he announced his theory of the Leyden flask, in
his public lectures, and in his last works. No better comparison was
then known, in the language of philosophy, to express this action. It
however affords me great pleasure, that I can now substitute for it
the pile discovered by Volta, which is perfectly consistent with the
system of Galvani; and since I am ready to allow that the invention of
the metallic pile gives Volta a title to the discovery of metallic
electricity, I hope the discovery of animal electricity, properly so
called, will be allowed to Galvani, as similar phænomena are exhibited
by the nervous and muscular systems, independently of common
electricity.
But some important questions in regard to Galvanism still remain to be
answered, such as the following: whether the action of chemical
combinations be the cause of Galvanism, or whether Galvanism be the
cause of chemical combinations. In my opinion, we have not yet a
sufficient number of data to determine this point. It may also be
asked, whether Galvanism be of the same nature as electricity, but
differently modified by the animal organization. For my part, until
their identity be proved by further researches, I shall be contented
with admitting that there is a great analogy between them.
But leaving these questions, the discussion of which might be
premature, it will be better to deduce general corollaries from the
series of experiments already detailed.
COROLLARY I.
It is found that there is a real attraction between certain parts of
animals; and this tends to confirm the idea of a sort of atmosphere
peculiar to parts of animals, as has been suggested by Humboldt. By
these means it will perhaps be one day possible to explain, with less
difficulty, the correspondence of some sensations in the animal
machine.
COROLLARY II.
The action of Galvanism on the aëriform fluids may serve to explain
its influence over the animal fluids by the oxidation of the humours,
and other phænomena which hitherto have been explained only in a
hypothetical manner.
COROLLARY III.
Fishes, and several amphibious animals which live under water,
sometimes approach the surface on certain changes of the atmosphere.
When the before-mentioned experiments on the Galvanic atmosphere are
considered, we may easily explain, why those changes which take place
in distant parts of the atmosphere are communicated to the element in
which these animals reside.
COROLLARY IV.
It has been ascertained, that water saturated with salts, and in
particular with muriate of soda, contributes a great deal to increase
the effects of Galvanism. It is well known also, that fishes, as
compared with other animals, possess a very high degree of vitality;
and hence we have reason to admire the wisdom of nature in making the
sea, which is destined for the abode of fishes, to be abundantly
saturated with muriate of soda.
COROLLARY V.
As Galvanism possesses great activity in chemical decompositions, it
cannot remain in a state of inaction; but must necessarily produce
great changes in the animal fluids and functions.
COROLLARY VI.
This principle, to which some of the grand operations of nature have
been entrusted, is not hypothetical; since it has been proved, that as
there is a metallic arc and a metallic pile in the mineral kingdom,
there is also an animal arc and an animal circle in the animal
kingdom; which may one day throw great light on the progress of
medicine, and be productive of considerable benefit to the human race.
PART THE SECOND.
ON THE INFLUENCE WHICH GALVANISM HAS ON THE VITAL POWERS.
To conduct an energetic fluid to the general seat of all impressions;
to distribute its influence to the different parts of the nervous and
muscular systems; to continue, revive, and, if I may be allowed the
expression, to command the vital powers; such are the objects of my
researches, and such the advantages which I purpose to derive from the
action of Galvanism.
The discovery of the Galvanic pile by the celebrated Volta has served
as a guide to enable me to obtain the most interesting results; and to
these I have been conducted by numerous researches and a long series
of experiments. I have examined the whole range of nature, and the
grand family of animals has afforded me the means of making
observations, highly interesting to physiology, on the whole œconomy
of the vital powers. My experiments on this subject I shall divide
into two Sections.
SECTION I.
_Galvanism applied to various quadrupeds, birds, and other
warm-blooded animals._
EXPERIMENT I.
The head of an ox, recently killed, was subjected to the action of a
pile (Plate II. fig. 1.) composed of fifty plates of copper and zinc,
separated, as usual, by small pieces of pasteboard moistened with a
solution of muriate of soda. Having moistened one of the ears with the
same solution, by means of a syringe, I introduced into it one
extremity of a metallic wire. I then formed an arc with this wire to
the summit of the pile, and by means of another wire made a
communication between the bottom of the pile and the nostrils. When
this apparatus was applied, the eyes were seen to open, the ears to
shake, the tongue to be agitated, and the nostrils to swell, in the
same manner as those of the living animal, when irritated and desirous
of combating another of the same species.
I then moistened both the ears with salt water, by the same method as
before, and inserted into each an extremity of one of the arcs. When
the Galvanism was communicated, the movements already described were
reproduced; but they appeared to be much more violent.
EXPERIMENT II.
A pile composed of a hundred pieces of silver and zinc (Plate II. fig.
2.) being employed, the tongue issued from the mouth four inches, and
re-entered it an inch, on each application of the arc; notwithstanding
the resistance opposed by the teeth which pressed against it: so that
after four or five applications of the arc it was entirely restored to
its usual situation.
I repeated this curious experiment several times at Bologna and Turin,
and lately at London before their Royal Highnesses the Prince of
Wales, the Duke of York, the Duke of Clarence, and the Duke of
Cumberland, who seemed to be much interested in my researches. I
showed them that the tongue returned without being touched, merely by
forming an arc between distant parts, such as the spinal marrow and
the cervical or nasal muscles. A person who held the extremity of the
tongue with a pair of pincers felt the effort it made to return every
time that the Galvanism was applied.
EXPERIMENT III.
With the same apparatus I suspended from the extremity of the
conducting arc the posterior half of a frog, by bending the iron wire
at right angles into a small elbow; and then, instead of making the
tongue touch the extremity of the arc, I brought it into contact with
one of the paws of the frog, while the other extremity of the wire
rested on the summit of the pile.
When this arrangement was made, I not only obtained the same
contractions in the head of the ox, but I observed also that when the
paw of the frog ceased to be in contact with the tongue, it was
attracted by the latter, which produced in it oscillations, so that it
formed a kind of Galvanometer; for the thighs of the small animal
diverged more or less according to the intensity of the fluid which
passed through them, and were restored to their former position when
the paw of the frog and the tongue of the ox were again brought into
contact. These oscillations continued about six minutes.
Suspecting, however, that the crural nerves might have some share in
these phænomena, independently of the pile, I cut these nerves, and
under similar conditions I obtained the same results.
EXPERIMENT IV.
Being desirous to repeat the above experiments on the heads of other
oxen, and on those of sheep and lambs, varying the pile, both in
regard to its nature and the number of pieces, I constructed three
piles of twenty-five, fifty, and a hundred and twenty pieces of silver
and zinc. The results, however, differed from the preceding only in
the greater or less intensity of the contractions, according as one or
the other apparatus was applied to the same animals. I remarked in
particular, that the combination most favourable to muscular
contractions is obtained, when the arc is established from the ears to
the spinal marrow. In this case the eye is so much affected, that the
eye-lids open entirely while the eye-ball turns round, and projects
somewhat from its socket, as sometimes happens in the most violent
madness.
EXPERIMENT V.
Having provided an ox recently killed, the head of which was not cut
off, I formed an arc from one ear to the other, interposing the pile.
The immediate result was a commotion so violent in all the extremities
of the animal, that several of the spectators were much alarmed, and
thought it prudent to retire to some distance. I then cut off the
head, and formed an arc from the spinal marrow, first to the
diaphragm, and then to the sphincter ani. In the first case, the
diaphragm experienced violent contractions; in the other I obtained a
very strong action on the rectum, which even produced an expulsion of
the fæces.
EXPERIMENT VI.
To give more extent to my experiments, I thought proper to repeat them
on lambs, chickens, and other warm-blooded animals; and without
enumerating such phænomena as are common, I shall only observe, that
the tongue, which was projected beyond the lips, again returned into
the cavity of the mouth, after several applications of the arc, as was
the case in the second experiment. The movements of the ears and
eye-lids were stronger than in the other parts. Comparative anatomy
must explain why this phænomenon, so striking in animals of this kind,
is not observed in man.
EXPERIMENT VII.
The observations which I had made on the Galvanism of the pile excited
my curiosity so much, that I was induced to try some comparative
experiments by means of common electricity. With this view I placed an
iron wire in each ear of a lamb, and discharged through it twice in
succession a Leyden flask, the two coatings of which were in
communication with the wires applied to the ears. By these means I
obtained contractions, but weaker than those produced by the pile; and
I always observed the same result in other warm-blooded animals.
EXPERIMENT VIII.
Having repeated the same experiments on live chickens, I found, to my
great surprise, notwithstanding the weakness of their organization,
that they sustained with firmness the strongest shocks, communicated
several times, with a pile composed of fifty plates of silver and
zinc. Though apparently dejected, and almost on the point of
expiring,—as soon as I interrupted the action of the pile, they
fluttered their wings, and seemed to congratulate themselves on their
escape from danger.
The curiosity natural to a philosopher induced me to subject these
birds to anatomical dissection, that I might examine what effects had
been produced on the animal machine by these convulsions. The
principal phænomena which I observed were extravasated blood in the
muscles; a derangement of the humours in different parts; the
intestines removed from their usual seat, and thrown towards the
pelvis. At some future period, I purpose to examine how long these
animals are capable of living under the continued action of Galvanism,
applied to them in different ways.
EXPERIMENT IX.
I applied the Galvanic action to a pullet just killed, forming an arc
from one of the ears to the other. When this arrangement was made, I
observed contractions not only in the feet, but also in the wings and
the whole animal machine. The same phænomena were produced by the same
means in two other pullets. I then combined the different parts of
these three pullets in such a manner, that the head of the second was
joined to the foot of the first, and the head of the third to the head
of the second. An arc being then formed to the two extremities of this
chain of animal parts, I was much pleased to see the three pullets
move their wings and their feet at the same time.
EXPERIMENT X.
The results of the preceding experiments led me to examine the power
of an arc formed by animal moisture. For this purpose, having
connected the heads of two oxen, (Plate II. fig. 3.) by bringing near
each other the sections of the neck, I established an arc from the
summit of the pile to one of the ears of one head, and another from
the base of the pile to one of the ears of the other. When this
arrangement was made, I observed that both the heads exhibited evident
signs of muscular contractions.
EXPERIMENT XI.
The trunks of two calves being united by the sections of the neck, and
an arc being established by the interposition of the pile from the
anus of the one to that of the other, both the trunks received, at the
same time, a commotion, but not very violent. I repeated this
experiment on the trunks of two lambs, but with a more striking
result, as all the extremities and muscles experienced violent
convulsions. A glass vessel, employed for the experiments, which stood
on the table, was overturned by one of the extremities, and thrown to
the distance of about two feet. I tried other combinations, but the
contractions were weaker.
EXPERIMENT XII.
Having sawn open the skull, I directed the action of the pile to
different parts of the brain, in the same order as they occurred in
the course of anatomical dissection. All these parts appeared to be
affected by the Galvanic force; but its action was stronger on the
corpus callosum and the cerebellum. The same result nearly was
obtained, when I repeated the experiment on the heads of different
calves and lambs.
EXPERIMENT XIII.
The heart of an ox, removed from the body, being exposed to the action
of Galvanism, though the pile was very powerful, exhibited no signs of
muscular contraction. I repeated the same experiment on the heart of
an ox, without removing it from the body, and on the hearts of several
dogs, one arc being applied to the spinal marrow, while the other
touched sometimes the surface of the heart, and sometimes penetrated
into its substance; but with the same result: no muscular convulsions
were produced.
EXPERIMENT XIV.
I prepared some frogs; and having waited till the motion of the
ventricles of the heart had become very slow, and almost
imperceptible, I communicated to them the Galvanic influence, and it
appeared to me that some movements were produced in the ventricles. I
repeated this experiment lately on the heart of a rabbit, and with the
same success. Having tried the hearts of several calves and dogs, I
could not observe any decided motion in the ventricles; but I remarked
that the Galvanic power exercised a strong action on the auricles.
EXPERIMENT XV.
Without taking into consideration the differences in the action of
Galvanism on the heart, according to the different applications and
the different kinds of animals subjected to experiment, I observed,
that after this muscle has lost its susceptibility to the action of
Galvanism, the other muscles still retain it in a very high degree.
This effect is very striking in regard to the heart and the muscles of
oxen and dogs; and this corresponds with what has been stated by the
Commissioners of the French National Institute in their Report.
Speaking of the anomalies found in this respect in the heart, they
conclude _that it is at any rate certain that this organ loses, in a
very short time, and much sooner than the other muscles, the faculty
of being agitated by Galvanism_.
EXPERIMENT XVI.
All the observations I was able to make on the involuntary muscles
will be found in the same Report, from which the following is an
extract: “Dr. Grapengiesser says, that he saw the vermicular motion of
the intestines increased by the action of Galvanism in a living
subject, whose large intestines protruded beyond the abdomen, in
consequence of a scrotal hernia. Professor Aldini made us observe the
same effect on the intestinal canal of a dog. We perceived also very
evident contractions in a portion of the stomach, separated from the
animal. We saw the auricles of the heart contract; but never found
this to be the case with the ventricles.”
EXPERIMENT XVII.
As I found it difficult, in the course of my travels, to obtain large
animals for my experiments, a desire of prosecuting my researches
induced me to be satisfied with such small animals as were easiest to
be procured. I therefore declared war against the dogs, which
exhibited the same phænomena as oxen, and with the greatest energy, as
may be seen by the following extract from the before-mentioned Report
of the Commissioners of the French National Institute: “The head of a
dog being cut off, Aldini subjected it to the action of a strong pile,
by which means the most frightful convulsions were produced. The mouth
opened, the teeth gnashed, the eyes rolled in their orbits; and, if
the imagination had not been restrained by reason and reflection, one
might have almost believed that the animal was restored to life, and
in a state of agony.”
EXPERIMENT XVIII.
The head and trunk of a dog, separated from each other, and placed in
such a manner as to leave an interval of about a foot between them
(Plate II. fig. 4.), were made to move simultaneously by applying the
Galvanic action to one of the ears, and to a small incision made in
one of the extremities of the trunk. I saw the same effect produced in
a public sitting held at the _Hôpital de la Charité_ at Paris. In this
case, the distance between the head and trunk was a foot and a half.
EXPERIMENT XIX.
In the preceding experiments, it is always necessary that the part of
the table which forms the interval between the head and trunk should
be moistened with salt water, or some other _conducting fluid_.
Considered in this point of view, the head and trunk mutually form an
arc which conducts the Galvanic action; so that the contractions
excited at the same time do not depend on the particular organization
of the animals subjected to experiment. This I confirmed by producing
simultaneous contractions in the trunk of a dog combined with the head
of a rabbit, and vice versa.
EXPERIMENT XX.
At the School of Medicine at Paris, in presence of the Commissioners
of the French National Institute, and of Professor Huzzard, I tried
the action of Galvanism on a horse which had been killed by the
insufflation of air into the jugular veins. The trunk exhibited no
extraordinary motion; but the head was violently agitated. A very
sensible gnashing of the teeth was produced, and all the muscles
performed, in a surprising manner, the same motion as is exerted
during the time of mastication. There was even a visible excretion of
the saliva. Of all the heads hitherto tried, that of the horse
exhibited the most violent motion by the action of Galvanism.
EXPERIMENT XXI.
Having performed this series of experiments, it was necessary that a
comparison should be made, cæteris paribus, between the action of
those stimulants proposed by the celebrated Haller, and the means here
used to excite the action of Galvanism. For this purpose I employed a
head weakened to such a degree that it was no longer sensible to the
action of the Hallerian stimulants applied to the muscles and nerves,
and then to different parts of the brain laid bare, and separated one
from the other. I tried the action of the sulphuric and nitric acids,
and the effect of the bistouri, but without ever producing the
smallest contraction in warm-blooded animals: on the other hand, the
action of Galvanism, on these parts, in the above state, occasioned
very powerful muscular contractions.
SECTION II.
_Experiments made on human bodies after death._
From the experiments already described, one might by analogy
conjecture what effect the action of Galvanism would produce on that
noble being man, the sole object of my researches. But to enable
philosophers to judge with more certainty respecting the effects of
this wonderful agent, it was necessary to adhere to certain
conditions, and to apply it immediately after death. The bodies of
persons who had died of disease were not proper for my purpose;
because it is to be presumed, that the development of the principle
which occasions death destroys the elasticity of the fibres, and that
the humours are changed from their natural to a corrupted state. It
was therefore necessary to obtain the human body while it still
retained, after death, the vital powers in the highest degree of
preservation; and hence I was obliged, if I may be allowed the
expression, to place myself under the scaffold, near the axe of
justice, to receive the yet bleeding bodies of unfortunate criminals,
the only subjects proper for my experiments. In consequence of an
application made for that purpose, I obtained from Government the
bodies of two brigands, who were decapitated at Bologna in the month
of January 1802. As both these individuals had been very young, and of
a robust constitution, and as the parts exhibited the utmost
soundness, I entertained strong hopes of obtaining the happiest
results from my proposed researches. Though accustomed to a more
tranquil kind of operations in my closet, and little acquainted with
anatomical dissections, the love of truth, and a desire to throw some
light on the system of Galvanism, overcame all my repugnance, and I
proceeded to the following experiments.
EXPERIMENT XXII.
The first of these decapitated criminals being conveyed to the
apartment provided for my experiments, in the neighbourhood of the
place of execution, the head was first subjected to the Galvanic
action. For this purpose I had constructed a pile consisting of a
hundred pieces of silver and zinc. Having moistened the inside of the
ears with salt water, I formed an arc with two metallic wires, which,
proceeding from the two ears, were applied, one to the summit and the
other to the bottom of the pile. When this communication was
established, I observed strong contractions in all the muscles of the
face, which were contorted in so irregular a manner that they
exhibited the appearance of the most horrid grimaces. The action of
the eye-lids was exceedingly striking, though less sensible in the
human head than in that of the ox.
EXPERIMENT XXIII.
Having established an arc from the top of the left ear, and then from
the bottom of that ear to the tongue, drawn about an inch without the
mouth, contractions were observed in the face, and the tongue sensibly
returned into the mouth. I then touched the upper or lower lips, and
obtained contractions, which were remarkable chiefly in all the
muscles of the left part of the face; so that the mouth appeared as if
distorted by a partial kind of palsy. On the first application of the
arc, a small quantity of saliva was discharged from the mouth.
EXPERIMENT XXIV.
I caused the head to be shaved exactly above the parietal protuberance
on the right side; and having moistened the integuments, armed with
silver and zinc, I established a communication by means of the pile
between the parietal bone and one of the ears. I obtained
contractions, but weaker than those observed when the arcs were formed
according to the different methods already described.
EXPERIMENT XXV.
Having formed an arc from the ears to different parts of the face,
moistened with a solution of muriate of soda, such for example as the
nose and forehead, I always observed violent contractions. But the
contractions were stronger when, instead of the first-mentioned pile,
I employed another consisting of fifty plates of copper and zinc. I
even still decreased the number of plates, in order that I might try,
in the course of these experiments, the different degrees of activity
which the pile would exhibit.
EXPERIMENT XXVI.
The head of the other criminal being brought to me after I had
employed about half an hour in these experiments, I repeated them on
this second head, and found the results to be analogous to those
before obtained. But the contractions produced in the second head were
stronger in consequence of its greater vitality: the vitality of the
first seemed to have been nearly exhausted.
EXPERIMENT XXVII.
Being desirous to examine, according to the principles of Galvani, the
power of an arc of animal moisture in warm-blooded animals, I
recollected that I had several times observed simultaneous convulsions
produced by these means in two frogs, and recently in the heads of two
oxen, the arc being conveyed from the one to the other in different
ways.
I placed the two heads in a straight line on a table, in such a manner
that the sections of the neck were brought into communication merely
by the animal fluids. When thus arranged, I formed an arc from the
pile to the right ear of one head, and to the left ear of the other,
and saw with astonishment the two heads make horrid grimaces; so that
the spectators, who had no suspicion of such a result, were actually
frightened. It was however observed, that the convulsions excited in
the heads disposed in this manner, were not so strong as those
produced when I performed the experiment on each head separately. It
is certain that, in this experiment, the arc of animal moisture
supplies the place of a continuation of the nervous and muscular
fibres.
EXPERIMENT XXVIII.
Having tried the effect of Galvanism on the exterior part of the head,
I proceeded to examine the phænomena exhibited by the interior organs
when treated in the same manner. I therefore removed the upper part of
the cranium by a section parallel to its base, uncovered the pia
mater, and established an arc from one of the ears to the medullary
substance. On the application of the arc strong convulsions were
observed in the face. While preparing the brain for my experiments, I
remarked that, in dividing the muscles of the forehead, at each stroke
of the dissecting knife, very strong contractions, which continued
after the dissection was finished, were excited in the muscles of the
face. I was informed that this is an uncommon phænomenon in anatomical
dissections; and therefore I shall leave it to anatomists to determine
whether it was occasioned, either in whole or in part, by the
preceding action of the pile.
EXPERIMENT XXIX.
Having then separated the lobes of the brain, I applied the arc to the
corpus callosum, to the ears or to the lips, and found that the whole
osseous box and the muscles of the face were violently agitated. Some
of the spectators even imagined that the corpus callosum itself was
affected by a peculiar convulsion; but it is possible that this
emotion was owing to a mechanical impulse which shook the whole head.
New experiments will, therefore, be necessary before any thing further
can be said in regard to this observation.
EXPERIMENT XXX.
Having carried the dissection to the olfactory nerves, and even to the
crossing of the optic nerves, I formed an arc from these parts to the
lips and the eyes, and obtained contractions, but very weak in
comparison of the preceding. I observed that on touching the optic
nerves with one of the arcs no sensible convulsions were produced in
the eye-lids.
EXPERIMENT XXXI.
This mutilated head, which had been so long the subject of
observation, was united by the plane of the section to that of the
other criminal, which had not been subjected to anatomical dissection.
I then applied two arcs, making one of them to communicate with the
summit of the pile and the right ear of one head, and the other with
the bottom of the pile and the left ear of the second head. Both heads
experienced contractions similar to those described in the 27th
experiment; but in the head which had already been employed they
appeared to be weaker.
EXPERIMENT XXXII.
After these experiments on the head, I proceeded to the trunk of the
second criminal, which I conceived to be most proper for my purpose.
I think it necessary here to observe, that the body had been exposed
for about an hour, in an open court, where the temperature was two
degrees below zero. The muscles of the fore-arm and the tendinous
parts of the metacarpus being laid bare, an arc was established from
those muscles to the spinal marrow. In consequence of this
arrangement, the fore-arm was raised, to the great astonishment of
those who were present.
EXPERIMENT XXXIII.
Having established an arc between the biceps muscle of each arm, which
I had laid perfectly bare, I obtained similar contractions, but
somewhat weaker than in the preceding case.
EXPERIMENT XXXIV.
Having laid bare the tendons of the fingers, on the back of the hand,
I established an arc between that region and the spinal marrow, and
obtained strong contractions in the fingers and in the whole hand.
EXPERIMENT XXXV.
Proceeding to the lower extremities, I formed an arc from the spinal
marrow to the vastus internus, vastus externus, sartorius, and other
muscles, and obtained strong contractions in all these muscles. Having
removed the arcs and the pile, the muscles retained a small
oscillatory motion, which continued for ten minutes. I observed the
same phænomenon in the muscles of the neck, when I established an arc
between the spinal marrow and various other parts of the trunk.
EXPERIMENT XXXVI.
Having applied the arc to the spinal marrow and the uncovered muscles
of the under part of the tarsus of the right foot, the extensor
muscles of all the toes, and particularly of the great toe,
experienced very sensible contractions. I repeated the experiment with
the arc applied, not to the spinal marrow, but to the uncovered
muscles of the thigh, employed in the preceding experiment, and found
the contractions excited to be much stronger. In like manner, the
muscles of the soles of the feet, when I established an arc between
them and the muscles of the thigh, manifested much stronger
contractions than when the arc extended to any other distant part.
EXPERIMENT XXXVII.
Having examined the force of the contractions, when the arcs were
applied to the surface of the muscles of the extremities, I tried what
effect would be produced by introducing them into their substance. In
this case, the energy of the contractions was much increased.
EXPERIMENT XXXVIII.
After trying the action of Galvanism on the extremities, I resolved to
examine the trunk. With this view, having established an arc from the
spinal marrow to the muscles of the diaphragm, I obtained very
sensible contractions every time the arc was applied.
EXPERIMENT XXXIX.
I then caused the thorax to be opened, that I might try the effects of
Galvanism on the most important of all the muscles, the heart. The
pericardium having been detached, I applied the conductor to the
principal organ of life, and I even caused it to be opened, to examine
whether there existed in any of its folds some fibre susceptible of
oscillation; but my researches were fruitless. This insensibility
ought, perhaps, to be ascribed to the want of a certain degree of heat
and of animal moisture, not to be found in a body two hours after
death. It will, therefore, be proper to repeat this experiment, taking
care to observe all those conditions which may be necessary to ensure
its success.
EXPERIMENT XL.
In the preceding experiment I observed that the diaphragm contracted,
and that the blood, which after this phænomenon I supposed to be
coagulated, flowed on the contrary from the vena cava inferior, and
the jugular veins, the moment the arc was applied, and appeared of a
bright red colour. Is there reason to conjecture that, though great
contractions cannot be produced, it is possible to excite in the
interior parts of the heart some oscillations analogous to those which
I observed in the muscles of the thigh and neck? This question can be
determined only by new experiments.
EXPERIMENT XLI.
I observed in these experiments, that the more the points of contact
of the arc with the biceps muscle were multiplied, the more the motion
of the arm was extended; especially when care was taken to insulate
the muscle by removing the integuments, and surrounding it with the
wire bent in the form of a ring. Having applied arcs to the biceps
muscle of each arm, I was much surprised to see the fore-arm and hand
of the extremity, where the before-mentioned ring was placed, rise
quickly to the height of about six inches.
EXPERIMENT XLII.
I repeated the experiment, forming the arc from the biceps muscle of
the fore-arm to the spinal marrow. By these means contractions so
violent were excited, that the anterior part of the arm, the whole of
which lay extended in a horizontal position, rose seven inches above
the plane of the table. Having placed on the palm of the hand a
metallic body, such as a piece of money, the hand at first supported
it for a little time; but at a certain degree of elevation it
projected it to some distance. I then substituted for the piece of
money a pair of iron pincers, about half a pound in weight; the hand
rose up and seemed to seize them; but at the highest degree of
elevation the contraction ceased, and the pincers fell. I observed
that the weight with which the hand was loaded, diminished the
elevating power of the arm very little. It may be proper to remark,
that the last two experiments were performed an hour and a quarter
after the execution, and those on the lower extremities almost two
hours.
If this experiment were speedily repeated, in order to take advantage
of the highest degree of vitality, loading the hand with different
weights in succession, till the motion of the hand should be totally
impeded, I am of opinion that an estimate might be formed of the
elevating force, according to the different degrees of vitality.
In the preceding experiments I have omitted certain observations,
which did not agree with those made on other warm-blooded animals. But
my silence deranges no theory; and, besides, facts not sufficiently
confirmed would have led me into physiological discussions of little
utility, as these points can be determined only by new experiments.
It is painful to a philosopher to reflect, that his doubts cannot be
cleared up until new victims shall fall under the sword of justice;
but the hope that his researches may lead to some new discovery
beneficial to mankind, in a physiological point of view, lessens in a
certain measure the disagreeable sensations excited by these
melancholy scenes.
An assassin decapitated at Bologna, in the month of January 1802,
afforded me an opportunity of verifying the truth of my former
observations. In my first experiments on the human body, the dura and
pia mater had been so little affected, that several of those present
concluded that these parts were absolutely insensible to the action of
the Galvanic pile; and this opinion was still further strengthened by
the authority of several able anatomists. On the other hand, many
warm-blooded animals, as will be seen hereafter, afforded contrary
results. It is certain that nature, which is always consistent with
itself in the action of that general principle which excites the
muscular forces, ought to exhibit in the human body the same phænomena
as those which constantly occur in other warm-blooded animals. I
mentioned this anomaly to several of my colleagues, and particularly
to that able anatomist Mondini, who, having made researches on this
subject, communicated to me the result of them, and directed all the
preparations necessary for the following experiments, modified
according to the general views collected in the preceding
observations.
EXPERIMENT XLIII.
The body of the criminal having been removed from the place of
execution to a neighbouring apartment, the trunk was placed on one
table, and the head on another. On the latter stood a pile, composed
of a hundred plates of zinc and copper, and on the former, a pile of a
hundred plates of silver and zinc. This apparatus tended greatly to
facilitate the rapid performance of the experiments, which were made
at the same time on all the parts of the body, and enabled us to take
advantage of its great vitality. I had with me a select company of
young physicians and surgeons, who, being much interested in the
progress of Galvanism, assisted me with great ardour. They were
divided into two parties, each of which was stationed around one of
the tables, in order that the operations performed at the one might
not interrupt those at the other. To gratify Professor Mondini, who
was desirous of seeing the muscular action in the whole head, an arc
was established from the spinal marrow to one of the ears, the pile
being interposed between them, and strong contractions were produced
in the whole face, as had been the case in all the other animals.
EXPERIMENT XLIV.
Having sawn through the scull with every possible precaution, and an
arc being established from the dura mater to one of the ears, the
usual contractions ensued. The pia mater was then uncovered, and, by
employing the same means, the same results and the same effects were
produced as had been obtained in other animals.
EXPERIMENT XLV.
The cortical substance in the left hemisphere was uncovered, and an
arc being extended from it to the right ear, the movements of the face
were exceedingly sensible in the part opposite to the uncovered
hemisphere. I repeated the experiment different ways with the same
results, and found, as I suspected, that this process put an end to
the anomaly observed in regard to the membranes and cortical
substance, which at first seemed to withstand the general action of
the Galvanic fluid, though it produced an effect on the other parts of
the brain. Dr. Mondini took care to remove the superfluous moisture,
both from the membranes and cortical substance, in order to prevent
all suspicion that it might facilitate a communication, in any manner,
with the medullary substance.
EXPERIMENT XLVI.
Dr. Mondini, with his usual ability, having exposed in the brain the
medullary substance, the corpora striata, the corpus callosum, the
thalami nervorum opticorum, and the cerebellum, and an arc being
formed of all these parts, we fully confirmed the results of the
experiments which had been before made on the bodies of other
criminals.
EXPERIMENT XLVII.
Having observed these phænomena in the head, we proceeded to the
trunk, which gave us results no less interesting. The body was sound
and robust, and indicated a constitution replete with vital energy. By
forming an arc from the spinal marrow to the biceps muscle, very
strong movements were produced throughout the whole body, and
particularly in the arm, which could not be bent without very great
exertion.
EXPERIMENT XLVIII.
By again applying the arc, according to the method detailed in the
41st experiment, the violence of the contractions was much increased.
The trunk was thrown into strong convulsions; the shoulders were
elevated in a sensible manner; and the hands were so agitated that
they beat against the table which supported the body.
EXPERIMENT XLIX.
A silver probe was inserted into the spinal marrow, and one of the
hands immersed in a solution of muriate of soda. I then applied one
extremity of the arc to the most distant part of the probe, and the
other to the surface of the water, by which means the Galvanism was
made to exercise its action without any immediate contact of the
animal parts. When this arrangement was formed, the arm, which hung
over the edge of the table, moved towards the breast, passing over the
space of about a foot and a half. By employing, at the same time, the
two piles composed of a hundred plates of copper and zinc, the
contractions were much increased. But this augmentation of force did
not exactly follow the ratio of the combined activity of the two piles
united.
EXPERIMENT L.
By forming an arc from the feet to the spinal marrow, first applying
armatures, and then employing a solution of muriate of soda as in the
preceding experiments, I obtained contractions, but weaker than those
in the upper extremities. As there was reason to suspect that this
diminution arose in part from the position of the trunk, I placed the
body in such a manner, that, while the thighs rested on the edge of
the table, the legs, which hung over it, were at full liberty to move.
This difference in position produced a difference in the results; and
I intend to repeat the experiment, according to this arrangement,
applying the arc directly to the crural nerves.
EXPERIMENT LI.
A small portion of the great pectoral muscle being detached from the
ribs, and exposed to the action of the pile, exhibited strong
contractions, and the motion of the diaphragm was also very
remarkable. The heart alone, though carefully subjected to all the
operations detailed in the 47th experiment, remained perfectly
motionless.
EXPERIMENT LII.
Having brought the separated head near to the neck of the trunk, I
established a communication between it and the trunk by means of the
animal moisture alone; and an arc being then formed from the head to
different parts of the trunk, sensible contractions were produced, and
particularly in the latter. This observation seems still further to
prove that an arc of moisture has power to excite muscular
contractions. In this, as well as in the preceding experiments, if any
of the spectators, while an arc was established by means of the pile,
brought a frog prepared in the usual manner near to the human body,
the frog experienced strong contractions, though at a distance from
the place to which the action of the Galvanism was determined.
EXPERIMENT LIII.
After three hours had been employed in these experiments, I conceived
the idea of trying the action of Galvanism on some parts of the body
separated from the trunk. One of the legs, therefore, was amputated
six inches above the joint of the knee; and an arc being established
from a point in the plane of the section to the knee, I obtained
contractions similar to those which had been produced before the limb
was separated from the body. I then formed an arc of moisture, by
applying the amputated limb to the trunk; and having determined the
action of the pile to the spinal marrow and the foot, I obtained very
sensible contractions. I observed, on this occasion, that a frog,
prepared some time before, and which was accidentally lying on the
table, at each application of the metallic arcs moved like an
electrometer, and thus confirmed the action of an arc of moisture.
EXPERIMENT LIV.
After a considerable time had been employed in the preceding
experiment, I endeavoured to revive the action of the Galvanism by
moistening the muscles with a solution of opium. By these means the
contractions seemed to be increased; and the case was the same in
other warm-blooded animals. A series of similar experiments, if
carefully made, would no doubt be attended with important results; as
they might enable us to ascertain the action of the different
stimulants proposed by Dr. Brown. But I must, in the mean time,
observe, that the before-mentioned effects of opium fully correspond
with those long ago observed by Galvani.
It results, in general, from my experiments, that moisture performs a
conspicuous part in producing contractions; and that it is even of
more importance than animal heat. I indeed find that muscular
contractions may be obtained after the body has thrown out a great
deal of its heat, even when it has cooled for several hours, and when
it has been exposed to a temperature below zero; for, if Galvanism be
communicated to a body in that state, muscular contractions will be
immediately excited; but they soon cease by the privation of animal
moisture. If a muscle, indeed, which has been laid bare resists the
Galvanic influence, its action may be speedily renewed by making an
incision into it, or into some of the muscles which surround it. I can
assert, that by this process partial contractions were produced in the
human body five hours after death, every time that the arcs were
applied to the muscular fibres.
Being worn out with this long series of experiments, I found it
necessary to abandon them; but, from the force of the contractions, it
could easily be seen that they might have been produced much longer.
Having communicated these results to the celebrated Caldani, Professor
of Anatomy in the University of Padua, he requested that I would
confirm the observations I had made by again applying Galvanism to the
membranes and to the cortical substance of the brain. He was unwilling
to give up the system of Haller without very positive proofs; and his
doubts were to me of great utility, as they induced me to establish
the action of Galvanism on these parts by the following experiments:
EXPERIMENT LV.
As these doubts related to a delicate point, which would have produced
some variation in the theory of a celebrated physiologist, I repeated
the experiment on the head of an ox newly killed, in the presence of
Professor Mondini, who made the necessary preparations. The dura mater
was laid bare; and the action of the Galvanism being conducted to it,
strong contractions were immediately produced. The same phænomenon
took place when the cortical substance was brought into contact with
one of the arcs. I repeated this experiment with the same success on
the heads of several oxen and lambs.
EXPERIMENT LVI.
When I passed through Turin, Professors Vassalli, Giulio, and Rossi
requested me to perform, in their presence, my principal experiments,
and those in particular which related to the membranes and the
cortical substance of the brain. They observed, at the same time, that
in uncovering the brain of an ox with a cleaver, some derangement, in
consequence of the agitation, might be effected in that organ, which
would perhaps produce an alteration in the results. Professors Giulio
and Rossi proposed therefore to uncover the brain by the trepan, which
gave a greater degree of precision to the experiment. The dura mater
of an ox being uncovered in this manner, it was subjected to the
action of Galvanism, and even with this mode of preparation the
muscular contractions every time the arc was applied were pretty
strong. The arc being determined to the cortical substance, the force
of the contractions seemed to be increased; and in general they
appeared to be more considerable in proportion as the arc was plunged
to a greater depth into the substance of the brain.
These gentlemen, in whose presence I performed my principal
experiments, having pursued my method after my departure, made some
observations which may be of great use to physiology. They had before
entertained strong doubts whether the heart was susceptible of the
Galvanic action, by means of simple armatures applied to the different
parts of that muscle; and such irregularity had been observed in the
results, that it appeared difficult to determine the question. I was
therefore exceedingly happy that I had had an opportunity of exciting
in others a desire to make new researches in regard to this point, of
so much importance. Professors Vassalli, Giulio and Rossi repeated and
modified my experiments on the heart in such a manner, that they
obtained in man, and warm-blooded animals, contractions similar to
those which I had observed only in cold-blooded animals. I wait for a
detailed account of these experiments, as well as of others made on
decapitated criminals[2], which were subjected to my processes. The
bodies were removed to the large hospital; and notwithstanding the
long period which had elapsed between the time of the execution and
that when the experiments were performed, they observed almost the
same phænomena.
The observation made on this criminal, that the vital powers exist so
long in the body after death, induces me to hope that I shall be able
to obtain similar results by the application of my method, in common
cases of suspended animation. But when employed for this laudable
purpose it should be modified in such a manner as to render
unnecessary those operations which are so painful to humanity. On this
account, I have invented a method by which muscular contractions may
be produced without the least incision or separation of the muscles.
It is so combined, that it cannot be rejected by the most rigorous
medical jurisprudence.
[2] Some account of the latter, from the _Journal de
Physique_, will be found in the Appendix.—TRANS.
EXPERIMENT LVII.
In order to try the vital force existing in the human body after
death, I immerse the hand in a solution of muriate of soda, and
establish an arc, one of the extremities of which is made to pass
round the fore-arm, while the other is brought into contact with the
bottom of the pile. I adapt to the extremity of another arc an elastic
probe, which is applied to one of the ears, moistened by means of a
syringe with the same solution, and connect the other extremity of the
arc with the summit of the pile. By this arrangement various
contractions, according to the different degrees of vitality in the
bodies, are observed, sometimes in the fingers, sometimes in the hand,
and sometimes in the whole arm. The fingers bend, and move in a
sensible manner; and sometimes the whole of the fore-arm proceeds
towards the breast. The importance of this method for determining the
duration of the vital powers after death may be readily comprehended.
Should means be found hereafter to make further discoveries in regard
to this interesting point, physiologists may then be able to determine
with certainty those cases when interment ought to be retarded; and
those where the good of society requires that every possible means of
resuscitation should be employed. In the large hospital of Bologna, I
made several observations on this subject; and remarked in particular,
how much the nature of the disease contributes, _cæteris paribus_, to
produce a difference in the duration of the muscular contractions. I
tried the case of death produced by putrid fevers, by pleurisies, by
wounds in the pericardium, by the scurvy, and by the consequences of
parturition; and I found a great difference in the degrees of
vitality, according to the circumstances of the disease, the age and
temperament of the individual; which confirms me in the opinion I
entertain, that these experiments, if long continued without
intermission by able physiologists, might be of the greatest benefit
to medicine.
These researches are not an object of mere curiosity; they seem to
open an extensive field for promoting the welfare of the human race,
and may be of service in cases of apparent death, occasioned by an
alteration of the brain, and sometimes in cases of asphyxia. Various
learned academies are entitled to great praise for having turned their
attention to this subject, and for having already recommended
different stimulants as proper for being used on such occasions. But I
must take the liberty of requesting that in similar cases the action
of Galvanism maybe tried, by employing the new method here proposed.
It is of great importance that the means of affording relief to the
sufferings of mankind should be multiplied, and especially in cases in
which the old system of medicine presents to us so few resources. In
the mean time I conceive it may be useful to make some trials on
animals thrown into a state of asphyxia different ways. These
researches may lead to valuable discoveries, and produce some light to
direct us in our attempts to save the lives of men. If the
encouragement I have received from the medical and philosophical
world, in general, induce others to pursue the same path, it will give
me great satisfaction. Galvanism is yet in its infancy; and when we
reflect on the slow progress which many other branches of science have
made, and how long they remained almost stationary before the full
importance of them was known, it would be presumption to set bounds to
that which is the subject of the present work. For my part, I spared
no pains during my short stay at Paris to exhibit my method, and to
make it publicly known. Dr. Pinel assisted at my experiments with the
utmost zeal, and was witness to muscular contractions excited in the
body of an old woman, who had died of a malignant putrid fever. The
interest which he took in my researches induced me to communicate to
him several plans I had formed for giving relief to some of those
unfortunate beings committed to his skill and beneficent care in the
_Hôpital des Foux_. I pointed out to him some particular cases where
the individuals, in consequence of a deep rooted melancholy, were
reduced almost to a state of idiotism, and in which Galvanism seemed
likely to be attended with the greatest benefit. In the last public
sitting of the Institute of Bologna, at which I was present, I
announced the complete cure of two lunatics performed in the Public
Hospital, in the presence of many of the medical pupils, and with the
assistance of the professors who superintend that establishment, and
who are now employed in confirming my method on other patients. I am
well aware that two cures are not sufficient to make operations of
this kind be admitted as general remedies; but they ought to encourage
physicians to prosecute this subject in order to ascertain how far
Galvanism can be considered as of utility in such cases, and to
endeavour by their labours to fill up the vacuity which still exists
in this part of medicine. I am ready to acknowledge that great caution
ought to be employed in performing such experiments; and for this
reason I purpose, in the third part of the present work, to lay before
the reader the reflections and observations of various ingenious men
who have made this department of Galvanism an object of their
researches.
But before I proceed further, I think it necessary to deduce from what
has been already said a few general corollaries.
COROLLARY I.
The muscles are affected by the action of the pile in a much more
powerful manner when they are laid entirely bare, and when the arc is
made to penetrate to a considerable depth in their substance.
COROLLARY II.
These convulsions are increased in proportion to the number of the
points of contact between the arc and the muscle.
COROLLARY III.
In many cases, muscular contractions are obtained by forming an arc
from one muscle to another.
COROLLARY IV.
Muscular contractions are almost always speedily obtained by the pile,
even when the means proposed by Haller fail to produce them.
COROLLARY V.
The heart, which, according to Haller’s principle, is the first muscle
that receives life and the last to lose it, in comparison of the other
muscles, can with difficulty be made to feel the influence of the
Galvanic action; while the other muscles always retain, a long time
after death, that vital force which it has never been found possible
to excite but by the impulse of Galvanism.
COROLLARY VI.
The partisans of Haller, to excite these contractions, often employ
stimulants, which alter the texture of the muscular fibre, and destroy
its continuity; an inconvenience which may be avoided by applying
Galvanism.
COROLLARY VII.
As the kinds of apparatus before mentioned are not applied to the
spinal marrow alone, but to the different nerves of the animal
machine, they may afford to the anatomist an experimental myology; by
means of which he can render sensible to the eye the fixed and
moveable points of the muscles, and the real extent of their action.
COROLLARY VIII.
The experiments made on the bodies of persons who died a natural
death, are of the greatest importance to physiology. I am strongly
inclined to think that, by pursuing these researches more in detail,
they will one day make us better acquainted with the character of the
vital powers, and the difference of their duration, according to
diversity of sex, age, temperament and disease, and even according to
diversity of climate and to the nature of the atmosphere.
PART THE THIRD.
ON THE POWER OF GALVANISM AS APPLIED TO MEDICINE.
If the doctrine of Galvanism have thrown considerable light on various
parts of philosophy and chemistry, it gives us reason to hope that it
may also be of benefit to medicine. The labours indeed of Galvani,
whose most ardent desire was that his discovery might be rendered
useful to mankind, were at length directed to this object, and his
wishes now begin to be realized; but I must request the reader not to
be too sanguine in his expectations, or to imagine that I here mean to
entertain him with a long series of wonderful or extraordinary cures
performed by means of Galvanism. I have no intention to decorate the
discovery of my late uncle with false glory. Though I possess neither
the same depth of knowledge, nor the same superiority of talents, I
have always endeavoured to imitate his moderation and prudence in the
application of his theory. I am fully convinced that much still
remains to be done, in order to discover the best methods of employing
this new agent; and that the facts respecting it, though numerous,
have not been reduced to principles sufficiently certain and
satisfactory. There are, nevertheless, some results and observations
exceedingly curious, which, if confirmed by new experiments and
researches, may enable us to obtain convincing proofs of its utility.
New facts, however surprising, are not to be despised merely on
account of their being different from any before observed. Those who
reject them, as some have done, ought first to show that they are
inconsistent with the principles of sound philosophy. Guided by these
reflections, and desirous of contributing, as far as possible, towards
the illustration of a new and very obscure subject, I shall lay before
the reader the result of my researches in the following articles.
SECTION I.
_Advantages which the medical administration of Galvanism has over
that of common electricity._
Several reasons have induced me to prefer the medical administration
of Galvanism by means of the pile, to that of artificial electricity.
In regard to the action of the common electric machine, the difficulty
of calling it forth properly during damp weather; the time required
for exciting it; the necessity of charging the jar every time it is
applied to the patient, are so many obstacles which render the
administration of common electricity inconvenient; and on this account
it is now much less used than formerly. On the other hand the pile,
according to the observations which I have had an opportunity of
making, acts in a uniform manner; is not sensible to the effects of
moisture; and forms a sort of Leyden flask, which has a continued
action that may be a long time employed. It may be considered as an
apparatus, which in itself contains a series of jars charged in
succession with different degrees of electricity.
I might here enumerate many differences which are found between the
administration of Galvanism and that of electricity. If electricity be
administered to a patient directly from the conductor, he receives
very little of its action; if a shock be given with the Leyden flask,
the action is exceedingly strong, but not permanent. On the other
hand, the pile has a strong and continued action, and occasions a
powerful circulation of the Galvanic matter, which after some time
produces very striking effects on the animal fluids. I might here
refer, by way of example, to the experiments made with Galvanism on
the blood, the bile, and the urine, which gave results I was never
able to obtain by common electricity. I shall mention, in the last
place, the great convenience of the pile, and the short space of time
in which Galvanism may be administered by it to a great number of
persons; and this advantage is sufficient, cæteris paribus, to render
it preferable in this respect to common electricity.