any sensible operation, but the next morning the animal was found dead.

In the eleventh experiment twenty grains of calcined magnesia were intended to be injected in five drachms of water. Scarcely half a drachm of the mixture was thrown in before convulsions ensued, and death was produced in less than four minutes. Death followed with equal rapidity after the injection of two drachms of undiluted alcohol, though the same animal had a few moments before borne two drachms of a mixture of equal parts of alcohol and water, without any very serious effects. A drachm and a half of a solution of tartrite of potass and soda was borne without any bad consequences, and seemed to cause a slight operation upon the bowels; but two drachms of the sulphate of magnesia, dissolved in half an ounce of water, caused death before one third of the quantity could be injected. The injections were all made into the jugular vein.

But the most interesting and important experiment was that performed upon his own person; and it is, we believe, the only well authenticated one, in modern times at least, in which any medicinal substance has been injected into the veins of the human subject. The substance selected in this instance was castor oil, and the quantity, half an ounce, a small dose for an adult. This was thrown in at an opening made in one of the veins of the arm, commonly selected for bleeding, and at the temperature of about seventy degrees. The intrepidity, resolution, and perseverance with which this experiment was designed and performed were not a little remarkable; and it was accomplished under circumstances of difficulty and embarrassment, which would have made almost any operator, particularly in his own person, shrink from following up his undertaking. His sensations after the experiment are best detailed in his own words.

I felt very well for a short time after the operation was finished. The first unusual sensation that I perceived, was a peculiar feeling, or taste of oiliness in the mouth, a little after twelve o'clock,' (about ten minutes after the oil had been completely injected,) very soon after, while I was washing the blood from my arm and hands, and was talking in very good spirits, I felt a slight nausea with eructations, and some commotion in the bowels, then a singular and indescribable feeling seemed very suddenly to ascend to my head. At the same instant, I felt a slight stiffness of the muscles of the face and jaw, which cut short my speaking in

the middle of a word, accompanied by a bewildered feeling in my head, and a slight faintness. I sat down, and in a few moments recovered myself a little.' pp. 114, 115.

For two hours after the completion of the experiment, Dr Hale continued to experience a strange sensation in his head, a degree of nausea, the oily taste in his mouth, and a tendency to alvine evacuation evinced by wandering pains &c. in his bowels, but without any real operation. The former symptoms left him after this period, but these deceptive feelings in the bowels remained through the evening, though there was no operation at any time, which could be attributed to the oil. The next day some unpleasant symptoms ensued of a different character.

'I had some pain in the head, and was all day much inclined to chilliness, though without true rigors. My arm was quite painful through the day. I had some fever and loss of appetite, and felt altogether too ill to make any use of my faculties, either of body or mind. This state continued several days; and when I began to recover from it, I found my strength so much diminished, that it required two or three weeks to restore it to its former vigor." p. 118.

These symptoms, we conceive, however, and we presume Dr Hale to be of the same opinion, are to be in a very considerable degree attributed to the sympathy of the system with the injury to the arm occasioned by the operation, and not to the effect of the presence of the oil in the circulation. They were not different in their nature, nor greater in degree, than might be expected from the violence done to the parts about the vein. And although they would not be necessarily always the consequence of such an operation, yet so great is the probability of their occurrence, as to form an almost insurmountable objection to the adoption of the practice.

But in addition to these unpleasant consequences, there seems to be sufficient ground on other considerations to relinquish the expectation of finding in the injection of medicines into the veins, an advantageous mode of introducing them into the system.

On a review of the whole subject,' says Dr Hale, ' we find that the evacuations, occasioned by the operation of emetics and cathartics, might be procured quite as effectually, and even more so, by injecting them into the veins, as by introducing them into the stomach; but that it would be dangerous in the extreme to administer in this manner any of the emetics, or of the more power

ful cathartics; and that the injection of even the milder cathartics is attended by much more pain and inconvenience, than can be counterbalanced by any advantages that it seems to promise. We must, therefore, regard this mode of administering medicines as too full of dangers to be entitled to confidence.' p. 135.

ers.

In this conclusion we perfectly agree, and presume that few, after the experience of Dr Hale, will be inclined to put it again to the test of experiment, either on themselves or othFor all practical purposes, there can be little room for difference of opinion about the expediency of adopting the injection of medicinal substances as a means of curing diseases. Whatever may be the results of this operation upon other animals, they never can inspire sufficient confidence to justify us in making our fellow beings the subjects of such a series of severe and hazardous experiments, as would be necessary in order to establish the practice upon a sure basis; so that even were it determined as a matter of physiological interest, that similar results follow from the injection of medicinal substances, in man as in other animals, we conceive that few would be hardy enough to take upon themselves the risk and responsibility of the operation, in cases of disease.

Dr Hale states very candidly, in his introduction, some of the objections to experiments upon living animals, and observes, with great truth, that thousands of animals have died in the cause of physiological science, whose deaths have scarcely added any thing to our knowledge of the laws or properties of the human system.' Now we are not all disposed to deny, that there are questions in physiology which can only be decided by means of experiments on living animals; and such experiments, when performed in the course of a regular train of investigation, may be made to throw much light upon some of the dark points in the science of life. But their necessity and importance has been, we conceive, very much overrated. They have been and are resorted to as modes of proof upon the most trivial occasions, and too often unlimited confidence has been placed upon the deductions drawn from them, when they least deserved it.

Experiments have an imposing air when brought in support of any opinion, and they are too apt to command our implicit belief, without a sufficient examination of their claim to it. Yet surely men are as liable to be mistaken in the results of the experiments they perform, as they are to be wrong in the opin

ions they hold. Before we give full faith to deductions from experiments made upon living animals, we ought to assure ourselves that the operator is competent to the undertaking. The qualities necessary to it are rarely to be met with; one should have, not only the anatomical knowledge and manual dexterity of the most accomplished surgeon; but a thorough acquaintance with the whole science of physiology, and more especially of the particular subject before him. He should add also to these qualifications a clear, unprejudiced, and philosophical mind, capable of drawing accurate inferences from the phenomena that occur. Yet these circumstances are seldom taken into consideration, and an experiment would be received as conclusive from a quarter, whence an opinion merely would meet with little regard. But it should be recollected, that there are probably more men qualified to form an opinion deserving of attention, than to perform an experiment; the latter presupposing even more rare qualities than the former. And, besides, when we decide between the comparative value of opinion and argument on the one hand, and experiment upon the other, we ought to consider that we are more competent judges of the former, than of the latter; we can estimate the weight and importance of men's arguments, and the grounds of their reasoning; but we cannot their powers of observing accurately, or of reporting truly. Hence the remark, we believe of Dr Cullen, that there were more false facts than false theories in medicine, is found abundantly true.

The zeal for matter of fact philosophy, which is so prevalent among some at the present day, makes it necessary that much caution should be used in placing dependence upon its results. This philosophy, when implicitly relied on, is fully as dangerous to the cause of truth as the theoretical, or even more so. Men generally theorize upon common and acknowledged facts, so that others can detect the fallacy of their opinions, if they are fallacious; but when they pretend to have opened a new field in nature and to found opinions upon discoveries made by themselves, the evil is more difficult to be remedied, because in such cases we commonly have just as much theory built upon facts, of the evidence for which we are not competent judges. We find, in truth, that experiments, apparently conclusive, are brought in favor of the most opposite opinions; and it would seem as if men formed their opinions first, and then looked about for experiments to support them. It seems impossible, after even the laceration occasioned by

the preparation for an experiment, and especially after the lesion or separation of the noble organs which are so frequently the subjects of them, that life should retain enough of the harmony, regularity, and consistency of its operations, for us to judge with certainty of the principles and laws, by which they are governed. Such, it appears to us, must be the disturbance among those functions, whose mutual relation is their mutual support, by so great violence to any of them, that no legitimate inferences can be drawn from the phenomena. which occur.

We have only to look at the history of some physiological questions for evidence of the truth of these remarks; in which, after some important facts have been brought to light with regard to them by men of genius, they have been involved in fresh darkness by the accumulation around them of a mass of ill-contrived and ill-digested experiments. Let us not be mistaken; we do not intend to deny, that experiments upon living animals, performed by those competent to the task, with relation to subjects which are capable of being illustrated in this way, and without such injury and laceration of organs as throw into complete disorder all the functions of the system, may be of much service in enlightening some parts of the science of physiology. But when they are performed in the mere wantonness of philosophy, with scarce any other definite object, than that of gaining a name by eliciting some striking phenomena in the struggles of nature, which shall have the air of important discoveries, they are useless at best.*

That we do not exaggerate in speaking on this subject, we think will be made evident by the following sketch of some interesting experiment on vomiting, performed within a few years at Paris.

M. Magendie, in order to prove that the stomach was inert in the act of vomiting, asserts, that when two fingers were introduced through an incision into the abdomen, the stomach was found not to act itself, but to be compressed between the diaphragm and abdominal muscles; that if the incision was enlarged so as to bring the stomach out of the wound, vomiting ceased, and the stomach remained quiet, although tartar emetic was injected into the veins that if the abdominal muscles are cut away, vomiting is still produced by the compression of the stomach against the linea alba by the diaphragm, but that if this latter organ be incapacitated by dividing the phrenic nerves, vomiting is at an end. To crown all, M. Magendie removed the stomach, substituted a pig's bladder, which he connected with the œsophagus, and then having sewed up the abdomen, injected tartarjemetic into the veins, and succeeded in producing vomiting.

So far all seems very well; but another inquirer, M. Maingault, having taken up the same subject, arrived by experiments performed like Magendie, or living animals, at results directly opposite. He succeeded in producing vomiting, by strangulating an intestine, and by injecting tartar emetic, after dividing the abdominal muscles, cutting them off from the body, dividing the