EXPERIMENTI.Onearc being applied to the mouth, and another to the ear, wetted with a solution of muriate of soda (common salt), Galvanism was communicated by means of three troughs combined together, each of which contained forty plates of zinc, and as many of copper. On the first application of the arcs the jaw began to quiver, the adjoining muscles were horribly contorted, and the left eye actually opened.EXPERIMENTII.On applying the arc to both ears, a motion of the head was manifested, and a convulsive action of all the muscles of the face: the lips and eyelids were also evidently affected; but the action seemed much increased by making one extremity of the arc to communicate with the nostrils, the other continuing in one ear.EXPERIMENTIII.The conductors being applied to the ear, and to the rectum, excited in the muscles contractions much stronger than in the preceding experiments. The action even of those musclesfurthest distant from the points of contact with the arc was so much increased as almost to give an appearance of re-animation.EXPERIMENTIV.In this state, wishing to try the power of ordinary stimulants, I applied volatile alkali to the nostrils and to the mouth, but without the least sensible action: on applying Galvanism great action was constantly produced. I then administered the Galvanic stimulus and volatile alkali together; the convulsions appeared to be much increased by this combination, and extended from the muscles of the head, face, and neck, as far as the deltoid. The effect in this case surpassed our most sanguine expectations, and vitality might, perhaps, have been restored, if many circumstances had not rendered it impossible.EXPERIMENTV.I next extended the arc from one ear to the biceps flexor cubiti, the fibres of which had been laid bare by dissection. This produced violent convulsions in all the muscles of the arm, and especially in the biceps and the coraco brachialis even without the intervention of salt water.EXPERIMENTVI.An incision having been made in the wrist, among the small filaments of the nerves and cellular membrane, on bringing the arc into contact with this part, a very strong action of the muscles of the fore-arm and hand was immediately perceived. In this, as in the last experiment, the animal moisture was sufficient to conduct the Galvanic stimulus without the intervention of salt water.EXPERIMENTVII.The short muscles of the thumb were dissected, and submitted to the action of the Galvanic apparatus, which induced a forcible effort to clench the hand.EXPERIMENTVIII.The effects of Galvanism in this experiment were compared with those of other stimulants. For this purpose, the point of the scalpel was applied to the fibres, and even introduced into the substance of the biceps flexor cubiti without producing the slightest motion. The same result was obtained from the use of caustic volatile alkali and concentratedsulphuric acid. The latter even corroded the muscle, without bringing it into action.EXPERIMENTIX.Having opened the thorax and the pericardium, exposing the heartin situ, I endeavoured to excite action in the ventricles, but without success. The arc was first applied upon the surface, then in the substance of the fibres, to the carneæ columnæ, to the septum ventriculorum, and lastly, in the course of the nerves by the coronary arteries, even with salt water interposed, but without the slightest visible action being induced.EXPERIMENTX.In this experiment the arc was conveyed to the right auricle, and produced a considerable contraction, without the intervention of salt water, but especially in that part called the appendix auricularis: in the left auricle scarcely any action was exhibited.EXPERIMENTXI.Conductors being applied from the spinal marrow to the fibres of the biceps flexor cubiti, the gluteus maximus, and the gastrocnemius, separately, no considerable action in the muscles of the arm and leg was produced.EXPERIMENTXII.The sciatic nerve being exposed between the great trochanter of the femur and the tuberosity of the ischium, and the arc being established from the spinal marrow to the nerve divested of its theca, we observed, to our astonishment, that no contraction whatever ensued in the muscles, although salt water was used at both extremities of the arc. But the conductor being made to communicate with the fibres of the muscles and the cellular membrane, as strong an action as before was manifested.EXPERIMENTXIII.By making the arc to communicate with the sciatic nerve and the gastrocnemius muscle, a very feeble action was produced in the latter.EXPERIMENTXIV.Conductors being applied from the sciatic to the peronæal nerve, scarcely any motion was excited in the muscles.EXPERIMENTXV.The sciatic nerve being divided about the middle of the thigh, on applying the conductors from the biceps flexor cruristo the gastrocnemius, there ensued a powerful contraction of both. I must here observe that the muscles continued excitable for seven hours and a half after the execution. The troughs were frequently renewed, yet towards the close they were very much exhausted. No doubt, with a stronger apparatus we might have observed muscular action much longer; for, after the experiments had been continued for three or four hours, the power of a single trough was not sufficient to excite the action of the muscles: the assistance of a more powerful apparatus was required. This shows that such a long series of experiments could not have been performed by the simple application of metallic coatings. I am of opinion that, in general, these coatings, invented in the first instance by Galvani, are passive. They serve merely to conduct the fluid pre-existent in the animal system; whereas, with the Galvanic batteries of Volta, the muscles are excited to action by the influence of the apparatus itself.From the above experiments there is reason to conclude:I.That Galvanism exerts a considerable power over the nervous and muscular systems, and operates universally on the whole of the animal œconomy.II.That the power of Galvanism, as a stimulant, is stronger than any mechanical action whatever.III.That the effects of Galvanism on the human frame differ from those produced by electricity communicated with common electrical machines.IV.That Galvanism, whether administered by means of troughs, or piles, differs in its effects from those produced by the simple metallic coatings employed by Galvani.V.That when the surfaces of the nerves and muscles are armed with metallic coatings, the influence of the Galvanic batteries is conveyed to a greater number of points, and acts with considerably more force in producing contractions of the muscular fibre.VI.That the action of Galvanism on the heart is different from that on other muscles. For, when the heart is no longer susceptible of Galvanic influence, the other muscles remain still excitable for a certain time. It is also remarkable that the action produced by Galvanism on the auricles is different from that produced on the ventricles of the heart, as is demonstrated in Experiment the tenth.VII.That Galvanism affords very powerful means of resuscitation in cases of suspended animation under common circumstances. The remedies already adopted in asphyxia, drowning,&c.when combined with the influence of Galvanism, will produce much greater effect than either of them separately.Toconclude this subject, it may be acceptable to the reader to have a short but accurate account of the appearances exhibited on the dissection of the body, which was performed with the greatest care and precision by Mr. Carpue.“The blood in the head was not extravasated, but several vessels were prodigiously swelled, and the lungs entirely deprived of air; there was a great inflammation in the intestines, and the bladder was fully distended with urine. In general, upon viewing the body, it appeared that death had been immediately produced by a real suffocation.”It may be observed, if credit can be given to some loose reports, which hitherto it has not been in our power to substantiate, that after this man had been for some time suspended, means were employed with a view to put an end to his sufferings.From the preceding narrative it will be easily perceived, that our object in applying the treatment here described was not to produce re-animation, but merely to obtain a practical knowledge how far Galvanism might be employed as an auxiliary to other means in attempts to revive persons under similar circumstances.In cases when suspended animation has been produced by natural causes, it is found that the pulsations of the heart and arteries become totally imperceptible; therefore, when it is to be restored, it is necessary to re-establish the circulation throughout the whole system. But this cannot be done without re-establishing also the muscular powers which havebeen suspended, and to these the application of Galvanism gives new energy.I am far from wishing to raise any objections against the administration of the other remedies which are already known, and which have long been used. I would only recommend Galvanism as the most powerful mean hitherto discovered ofassistingand increasing the efficacy of every other stimulant.Volatile alkali, as already observed, produced no effect whatever on the body when applied alone; but, being used conjointly with Galvanism, the power of the latter over the nervous and muscular system was greatly increased: nay, it is possible that volatile alkali, owing to its active powers alone, might convey the Galvanic fluid to the brain with greater facility, by which means its action would become much more powerful in cases of suspended animation. The well known method of injecting atmospheric air ought not to be neglected; but here, likewise, in order that the lungs may be prepared for its reception, it would be proper previously to use Galvanism, to excite the muscular action, and to assist the whole animal system to resume its vital functions. Under this view, the experiments of which I have just given an account, may be of great public utility.It is with heartfelt gratitude that I recall to mind the politeness and lively interest shown by the members of theCollege of Surgeons in the prosecution of these experiments. Mr. Keate, the master, in particular proposed to make comparative experiments on animals, in order to give support to the deductions resulting from those on the human body. Mr. Blicke observed that on similar occasions it would be proper to immerse the body in a warm salt bath, in order to ascertain how far it might promote the action of Galvanism on the whole surface of the body. Dr. Pearson recommended oxygen gas to be substituted instead of the atmospheric air blown into the lungs. It gives me great pleasure to have an opportunity of communicating these observations to the public, in justice to the eminent characters who suggested them, and as an inducement to physiologists not to overlook the minutest circumstance which may tend to improve experiments that promise so greatly to relieve the sufferings of mankind.
EXPERIMENTI.
Onearc being applied to the mouth, and another to the ear, wetted with a solution of muriate of soda (common salt), Galvanism was communicated by means of three troughs combined together, each of which contained forty plates of zinc, and as many of copper. On the first application of the arcs the jaw began to quiver, the adjoining muscles were horribly contorted, and the left eye actually opened.
EXPERIMENTII.
On applying the arc to both ears, a motion of the head was manifested, and a convulsive action of all the muscles of the face: the lips and eyelids were also evidently affected; but the action seemed much increased by making one extremity of the arc to communicate with the nostrils, the other continuing in one ear.
EXPERIMENTIII.
The conductors being applied to the ear, and to the rectum, excited in the muscles contractions much stronger than in the preceding experiments. The action even of those musclesfurthest distant from the points of contact with the arc was so much increased as almost to give an appearance of re-animation.
EXPERIMENTIV.
In this state, wishing to try the power of ordinary stimulants, I applied volatile alkali to the nostrils and to the mouth, but without the least sensible action: on applying Galvanism great action was constantly produced. I then administered the Galvanic stimulus and volatile alkali together; the convulsions appeared to be much increased by this combination, and extended from the muscles of the head, face, and neck, as far as the deltoid. The effect in this case surpassed our most sanguine expectations, and vitality might, perhaps, have been restored, if many circumstances had not rendered it impossible.
EXPERIMENTV.
I next extended the arc from one ear to the biceps flexor cubiti, the fibres of which had been laid bare by dissection. This produced violent convulsions in all the muscles of the arm, and especially in the biceps and the coraco brachialis even without the intervention of salt water.
EXPERIMENTVI.
An incision having been made in the wrist, among the small filaments of the nerves and cellular membrane, on bringing the arc into contact with this part, a very strong action of the muscles of the fore-arm and hand was immediately perceived. In this, as in the last experiment, the animal moisture was sufficient to conduct the Galvanic stimulus without the intervention of salt water.
EXPERIMENTVII.
The short muscles of the thumb were dissected, and submitted to the action of the Galvanic apparatus, which induced a forcible effort to clench the hand.
EXPERIMENTVIII.
The effects of Galvanism in this experiment were compared with those of other stimulants. For this purpose, the point of the scalpel was applied to the fibres, and even introduced into the substance of the biceps flexor cubiti without producing the slightest motion. The same result was obtained from the use of caustic volatile alkali and concentratedsulphuric acid. The latter even corroded the muscle, without bringing it into action.
EXPERIMENTIX.
Having opened the thorax and the pericardium, exposing the heartin situ, I endeavoured to excite action in the ventricles, but without success. The arc was first applied upon the surface, then in the substance of the fibres, to the carneæ columnæ, to the septum ventriculorum, and lastly, in the course of the nerves by the coronary arteries, even with salt water interposed, but without the slightest visible action being induced.
EXPERIMENTX.
In this experiment the arc was conveyed to the right auricle, and produced a considerable contraction, without the intervention of salt water, but especially in that part called the appendix auricularis: in the left auricle scarcely any action was exhibited.
EXPERIMENTXI.
Conductors being applied from the spinal marrow to the fibres of the biceps flexor cubiti, the gluteus maximus, and the gastrocnemius, separately, no considerable action in the muscles of the arm and leg was produced.
EXPERIMENTXII.
The sciatic nerve being exposed between the great trochanter of the femur and the tuberosity of the ischium, and the arc being established from the spinal marrow to the nerve divested of its theca, we observed, to our astonishment, that no contraction whatever ensued in the muscles, although salt water was used at both extremities of the arc. But the conductor being made to communicate with the fibres of the muscles and the cellular membrane, as strong an action as before was manifested.
EXPERIMENTXIII.
By making the arc to communicate with the sciatic nerve and the gastrocnemius muscle, a very feeble action was produced in the latter.
EXPERIMENTXIV.
Conductors being applied from the sciatic to the peronæal nerve, scarcely any motion was excited in the muscles.
EXPERIMENTXV.
The sciatic nerve being divided about the middle of the thigh, on applying the conductors from the biceps flexor cruristo the gastrocnemius, there ensued a powerful contraction of both. I must here observe that the muscles continued excitable for seven hours and a half after the execution. The troughs were frequently renewed, yet towards the close they were very much exhausted. No doubt, with a stronger apparatus we might have observed muscular action much longer; for, after the experiments had been continued for three or four hours, the power of a single trough was not sufficient to excite the action of the muscles: the assistance of a more powerful apparatus was required. This shows that such a long series of experiments could not have been performed by the simple application of metallic coatings. I am of opinion that, in general, these coatings, invented in the first instance by Galvani, are passive. They serve merely to conduct the fluid pre-existent in the animal system; whereas, with the Galvanic batteries of Volta, the muscles are excited to action by the influence of the apparatus itself.
From the above experiments there is reason to conclude:
I.
That Galvanism exerts a considerable power over the nervous and muscular systems, and operates universally on the whole of the animal œconomy.
II.
That the power of Galvanism, as a stimulant, is stronger than any mechanical action whatever.
III.
That the effects of Galvanism on the human frame differ from those produced by electricity communicated with common electrical machines.
IV.
That Galvanism, whether administered by means of troughs, or piles, differs in its effects from those produced by the simple metallic coatings employed by Galvani.
V.
That when the surfaces of the nerves and muscles are armed with metallic coatings, the influence of the Galvanic batteries is conveyed to a greater number of points, and acts with considerably more force in producing contractions of the muscular fibre.
VI.
That the action of Galvanism on the heart is different from that on other muscles. For, when the heart is no longer susceptible of Galvanic influence, the other muscles remain still excitable for a certain time. It is also remarkable that the action produced by Galvanism on the auricles is different from that produced on the ventricles of the heart, as is demonstrated in Experiment the tenth.
VII.
That Galvanism affords very powerful means of resuscitation in cases of suspended animation under common circumstances. The remedies already adopted in asphyxia, drowning,&c.when combined with the influence of Galvanism, will produce much greater effect than either of them separately.
Toconclude this subject, it may be acceptable to the reader to have a short but accurate account of the appearances exhibited on the dissection of the body, which was performed with the greatest care and precision by Mr. Carpue.
“The blood in the head was not extravasated, but several vessels were prodigiously swelled, and the lungs entirely deprived of air; there was a great inflammation in the intestines, and the bladder was fully distended with urine. In general, upon viewing the body, it appeared that death had been immediately produced by a real suffocation.”
It may be observed, if credit can be given to some loose reports, which hitherto it has not been in our power to substantiate, that after this man had been for some time suspended, means were employed with a view to put an end to his sufferings.
From the preceding narrative it will be easily perceived, that our object in applying the treatment here described was not to produce re-animation, but merely to obtain a practical knowledge how far Galvanism might be employed as an auxiliary to other means in attempts to revive persons under similar circumstances.
In cases when suspended animation has been produced by natural causes, it is found that the pulsations of the heart and arteries become totally imperceptible; therefore, when it is to be restored, it is necessary to re-establish the circulation throughout the whole system. But this cannot be done without re-establishing also the muscular powers which havebeen suspended, and to these the application of Galvanism gives new energy.
I am far from wishing to raise any objections against the administration of the other remedies which are already known, and which have long been used. I would only recommend Galvanism as the most powerful mean hitherto discovered ofassistingand increasing the efficacy of every other stimulant.
Volatile alkali, as already observed, produced no effect whatever on the body when applied alone; but, being used conjointly with Galvanism, the power of the latter over the nervous and muscular system was greatly increased: nay, it is possible that volatile alkali, owing to its active powers alone, might convey the Galvanic fluid to the brain with greater facility, by which means its action would become much more powerful in cases of suspended animation. The well known method of injecting atmospheric air ought not to be neglected; but here, likewise, in order that the lungs may be prepared for its reception, it would be proper previously to use Galvanism, to excite the muscular action, and to assist the whole animal system to resume its vital functions. Under this view, the experiments of which I have just given an account, may be of great public utility.
It is with heartfelt gratitude that I recall to mind the politeness and lively interest shown by the members of theCollege of Surgeons in the prosecution of these experiments. Mr. Keate, the master, in particular proposed to make comparative experiments on animals, in order to give support to the deductions resulting from those on the human body. Mr. Blicke observed that on similar occasions it would be proper to immerse the body in a warm salt bath, in order to ascertain how far it might promote the action of Galvanism on the whole surface of the body. Dr. Pearson recommended oxygen gas to be substituted instead of the atmospheric air blown into the lungs. It gives me great pleasure to have an opportunity of communicating these observations to the public, in justice to the eminent characters who suggested them, and as an inducement to physiologists not to overlook the minutest circumstance which may tend to improve experiments that promise so greatly to relieve the sufferings of mankind.