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

Front matter

AN ACCOUNT

*- Is I ^

OF

Preface

V 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, Mmj 12th, 1803.

Contents

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 . - - - - _ _ „ ^

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 _ ■„ _ q

Prop. III. Galvanism develops itself in a powerful manner, independently of metals, by means of the human animal machine - - ± - ~ _ « ... % _ g

Prop.

viii CONTENTS.

PAGE

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 - - - \%

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 Ley den flash, 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 Ley den flash, as to ell 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 - - .f* - - - — - - - - - - 29

Prop.

CONTENTS. k

PAGE

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 Ley den flask - - - - - - - - - - 34

Prop. 'XIII. Galvanism, in animals and in the pile, traverses large spaces with the same rapidity as the electric fluid -------- - - - - - - - - - - - 35

Prop. XIV. The muscular contractions, which, according to the observations of Galvani, are produced by an electric atmosphere zvhether 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 _ _ _ _ - _ _ _ . . _ . L - - - 41

Prop. XVI. If the general relation between Galvanism and electricity be examined, such a correspondence willbefowid 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 a

PART

CONTENTS.

Part The Second. Pace

ON THE INFLUENCE WHICH GALVANISM HAS ON THE VITAL POWERS - - - - - - 53

Section I. Galvanism applied to various quadrupeds, birds, and other war m-bhoded animals - - - - - - 54

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 - - - - - ~ .. ~ . ~ . " ... " ~ " 80* 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 aconomy - k - - - - - - 123

BlSSER-

CONTENTS. xi

PAGE

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 ----- 153

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, G julio, 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

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, accord-

2 An Account of the late Improvements in Galvanism,

ing 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

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.

Hav ing 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.

EX PER I-

EXPERIMENT Til

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 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.

PRO-

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 annuals, 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. Progs 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 of Galvanism.

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.

PROa

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 in.

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 phenomenon 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 phenomenon 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.

c

EXPE-

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.

PROof Galvanism.

|1

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 phenomena were exhibited with the head of an ox, which possessed an extraordinary degree of vitality.

c 2 PRO-

PROPOSITION V.

The effects of Galvanism, in the preceding experiments, do not depend on the action of any stimulant, zvhich occurs in performing the experiments, and ought not to be confounded ' with Hie 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 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.

PRO*

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 of Galvanism.

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 fallowing, 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 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 *.

EXPE-

* 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 natter 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, of Galvanism.

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.

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 mademe sensible of the importance of th 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 J 7 94. 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 stimulusarising 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.

d EXPERT-

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 tio-ht, at the insertion of the nerves into the muscles of the thigh.

PROof Galvanism.

PROPOSITION VII.

The heterogeneity of metals contributes, in a great degree, to excite muscular contractions with more facility, hut 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.

If several prepared frogs, ten or more for example, be placed on a table (Plate I. fig. 7.)? an d 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.

EXPERI-

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.

PROof Galvanism.

PROPOSITION VIII.

The Ley den 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 IT.

I provided for this experiment a Ley den 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 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.