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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