Mr. Smee seems to have at once concluded that he had found out the true secret of the disease; which is just as if he had argued from the presence of lice upon the persons of a dozen or two of hospital-patients affected with pneumonia or rheumatism, that they were the cause of the malady. We have carefully searched his treatise for that collection of evidence on the subject which is necessary to establish anything like a satisfactory relation of cause and effect; but we have been utterly disappointed. No locality is referred to as furnishing the aphides, save the potato-grounds at Clapton; no results are adduced of inquiries made in distant parts of the country; no proof is given that aphides placed upon healthy potatoplants, and allowed to propagate there, will produce the potato-disease in question. We cannot too strongly express our surprise, that a gentleman of Mr. Smee's scientific attainments should have ventured, after all the experience of former failures in accounting satisfactorily for the disease, to make such confident assertions regarding its cause upon so meagre an amount of evidence; when a very short delay would have been sufficient to enable him to procure such confirmatory testimony as the nature of the case admitted from every quarter of the kingdom, the attention of almost everybody being alive to the subject, and any new theory being caught at with avidity. We are not passing judgment upon the merits of the doctrine itself, for we do not consider ourselves competent to do so. The question is entirely one of evidence; since the à priori probability seems to us rather in Mr. Smee's favour than against him. And we understand that since the publication of his book, he has collected a large amount of evidence which he ought to have got together previously. But our sole concern is at present with the Treatise itself; and whilst we admit that it contains much valuable and interesting matter bearing upon the question at issue, we must repeat that it has not the slightest claim to be regarded as a justification of its author's assumptions.

ART. IV. The Nature and Faculties of the Sympathetic Nerve. By JOSEPH SWAN.-London, 1847. 8vo, pp. 55.

WE have every respect for Mr. Swan as an able and industrious anatomist; but we cannot feel a similar confidence in his physiological deductions. There is a vagueness about his language, when he is speaking of function, which forms a striking contrast to the clearness of his descriptions of structure, and which frequently (as it seems to us) misleads not only his readers but himself. In the preface to the pamphlet before us, he very clearly points out the difficulties attendant on the study of this division of the nervous system, and indicates the sources whence information may be obtained regarding its offices in the system. And in the second chapter, in which he describes the chief variations in the structure and arrangements of the sympathetic system in different classes of vertebrata, he gives many interesting anatomical particulars, which are valuable as data for physiological reasoning. But at the very commencement of his inquiries into the operations of the sympathetic, he betrays the want of those clear ideas of the relation between the animal and organic functions, on which

alone any correct notion of its influence on the latter can be erected. "The great object of the sympathetic nerve," he says (p. 4), "is to furnish the parts it supplies with an appropriate nervous excitement of such a quality as will ensure their functions without disturbing any other portion of the nervous system." Now the whole gist of the matter lies in the simple phrase ensure their functions." Every one knows that the sympathetic system is distributed chiefly to the heart and sanguiferous system, and to the intestinal canal. Does Mr. Swan assert that the heart cannot beat,-that the arteries, capillaries, and veins cannot convey blood, -that the several parts which they supply cannot draw from the blood the materials of their growth and nutrition,-and that the peristaltic movements of the intestinal tube cannot continue,-without the constant influence of this system of nerves? Such would appear to be his meaning, from various expressions scattered through the pamphlet, though he nowhere (that we have discovered) formally states these views. The following passage, which succeeds the one we have just quoted, will give a fair specimen of Mr. Swan's style; and we think that our readers' judgment upon it will correspond with our own:

"It connects in different degrees all the parts of the nervous system as an harmonious whole, but brings them in so slight a degree in communion with the sensory, as to allow only a perceptibility that can appreciate and respond to impulses without permitting them to proceed beyond the viscera. By preventing sensation, it becomes favorable to the production of involuntary motion, so that impulses on the lining membrane of the viscera, when sufficiently strong, are responded to, and the contraction of the muscular coat takes place. For these purposes it has a peculiar conformation which differs more or less from [that of] the other parts of the nervous system. Although it communicates with several cerebral nerves, it assimilates most to the fifth and spinal nerves. From these and their centres it probably derives some of their essential or diffusive influence for fortifying its vital powers, but admits only just as much of their faculties as corresponds with the functions of the parts it supplies. It is not less extensive in any of the four superior classes of animals, in proportion to the parts it actuates, but its structure is more or less complex, and in the same degree its faculties are more distant from, or approach nearer to, those of the rest of the nervous system, and accordingly are more or less independent. When its faculties are insufficient for the organs, having more complicated functions than those it generally promotes, branches of the fifth, the par vagum, and spinal nerves, are combined with portions of it; or when any organs, supplied by cerebral and spinal nerves, require a more general and higher excitement from the heart and arteries, they receive more branches from the sympathetic." (pp. 4, 5.)

We might easily show the vague and unsubstantial character of every one of the statements contained in this paragraph. What clear notion can be attached to "a perceptibility that can appreciate and respond to impulses," if no consciousness of those impulses be excited? What proof exists, that any such reflex action is performed by the ganglia of the sympathetic system? What definite meaning can be drawn from the "essential or diffusive influence for fortifying its vital powers," supposed to be derived by the sympathetic from the fifth cerebral and the spinal nerves? What ground is there for the assumption that the "faculties" of the sympathetic are "insufficient for the organs" it supplies, save the fact that other nerves are transmitted to them?-or what indication exists of the more general and higher excitement from the heart and arteries" asserted

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by Mr. Swan to be required by some organs, save the larger number of branches of the sympathetic proceeding to them? A clearer case of reasoning in a circle never came under our notice. We might quote an abundance of passages of the same kind; and upon the whole we feel constrained to say, that, except the few anatomical details contained in the second chapter, the pamphlet contains nothing but a series of vague and unmeaning speculations, couched in language which is a great deal too positive.

ART. V.-Elements of Chemistry, including the Actual State and Prevalent Doctrines of the Science. By the late EDWARD TURNER, M.D. F.R.S. L. & E. Eighth Edition. Edited by Baron LIEBIG, Professor of Chemistry in the University of Giessen, and WILLIAM GREGORY, M.D. F.R.S.E., Professor of Chemistry in the University of Edinburgh. Part I. Inorganic Chemistry.-London, 1847, 8vo. pp. 676.

THAT this work should so completely hold its ground, in spite of the competition of such Treatises as those of Professors Graham and Kane, to say nothing of the excellent Manuals of Fownes and Gregory, is of itself a sufficient testimony of the excellence of its original plan, and of the completeness with which it has been kept by its present editors, au courant with the rapid progress of Chemical Science. It is scarcely requisite, therefore, that we should do more than notice the appearance of the first part of a new edition; in the preparation of which Professor Gregory has obviously been at great pains to embody every new discovery of sufficient note, relative to the departments which it includes. The remaining portion of the work, embracing organic chemistry, is announced as speedily forthcoming.

The following extract from the Preface will be interesting to many of our readers, as affording a marked proof of that growing conformity of opinion upon fundamental questions, which is one of the most satisfactory indications of the real progress of science:

"Since the publication of the last edition, many continental chemists, including Liebig, Wöhler, Gmelin, and their numerous pupils, have finally adopted the British equivalents or atomic weights for those substances in regard to which a difference existed. This difference, therefore, no longer exists as far as concerns the chemists above named, and many others; who in their works now admit as we do water to be H O, not as formerly H, O; and chloride of potassium to be K Cl, and not as formerly K Cl,, &c. In short, the atomic weights of hydrogen, nitrogen, chlorine, bromine, iodine, and fluorine are now, by those chemists, assumed to correspond with their equivalents, where formerly the equivalent was made to contain two atoms." (p. iii.)

On the other hand, the editors have abandoned the old mode of regarding the combining equivalents of phosphorus, arsenic, and antimony, as twice their atomic proportion; and have thus substituted the simple formulæ PO,, As Og, and Sb O, for the more complex T, Os, As, Os, and Sb. O,, hitherto employed.

3

2

2

2

PART THIRD.

CONTRIBUTIONS TOWARDS THE ADVANCEMENT

OF THE

Natural History and Treatment of Diseases.

II. A SKETCH OF THE NATURAL CURE OF DISEASES.

BY WILLIAM MACKENZIE, M.D.

[THE following paper was long since published in the Glasgow Medical Journal (No. v, Feb. 1829) of which the accomplished writer was then Editor. It bears so appropriately on the general subject to which this part of our journal is for the present devoted, that we make no apology for reprinting it. We should be under still greater obligation to the author, if he would favour us with new and still more extensive illustrations of the important practical principles advocated by him.]

As the greater number of diseases which attack the human frame are susceptible of cure by the operations of Nature alone, while no one disease can be cured by the powers of Art alone, and as in all our attempts to cure diseases by artificial means, we imitate, or ought to imitate, the modes of cure followed by Nature, there is perhaps no question more truly of importance to medical practitioners than this :-What are the natural processes by which diseases are removed?

Before attempting to answer this question, it may not be improper to premise, that in speaking of the restorative power, or powers of Nature, and of the natural cure of diseases, I have no intention to admit the existence of any intelligent power or powers resident in the body, superintending or operating in the cure. The vis conservatrix and vis medicatria Naturæ have sometimes been spoken of in such a manner as might lead us to suppose that this was actually meant that it was not merely acknowledged that the body has in itself a power or condition, depending on its structure and on the revolutions of its functions, by which, in many cases, it resists the injuries which threaten it, and on many occasions corrects or removes the disorders induced in it, but that this preserving and remedying power was an actual agent superadded to the constitution of the body.

It will at once be seen that I refer in these remarks to the opinions of the celebrated Stahl, who explicitly founded his system on the supposition, that the power of Nature, so much talked of, did not in any degree depend on the structure and functions of the body, but belonged entirely to what he styled the Rational Soul. He maintained that, on many occasions, the soul acts even independently of the state of the body; and that without any physical necessity arising from that state, but purely in consequence of its intelligence, the soul

XLVI.-XXIII.

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perceiving the tendency of noxious powers threatening, or of disorders anywise arising in the system, immediately excites such actions in the body as are suited to obviate the pernicious consequences which might otherwise take place. This is a very fanciful, and I believe an entirely groundless hypothesis; but there is so much appearance of intelligence and design in the operations of the animal economy, that many medical authors have very much countenanced the same opinion. It may suffice at present to observe upon these notions, that the admitting of any such intelligent governor of the animal economy, would oblige us to reject all anatomical and physiological reasoning concerning diseases, and would render the whole practice of medicine capricious, and even dangerous. We see, in fact, the preposterous effects of such a system in the practice of Stahl himself and his followers, who, trusting much to the constant attention and wisdom of nature, proposed what they called the art of curing diseases with expectation, used, therefore, only very inert and frivolous remedies, were extremely reserved in the use of such general and powerful means of cure, as bloodletting, vomiting, and the like, zealously opposed the use of some of the most efficacious medicines, such as opium and Peruvian bark, and, in fact, converted the healing art, as far as they could, into a mere curious contemplation of diseases and of death.

I go on, then, in answer to the question already stated, to remark in the first place, that in some instances the natural cure of diseases is so direct and prompt, that we are unable to discover any process by which it is effected. Pain ceases to be felt-and the disease is at an end. Spasm relaxes—and the muscle returns under the control of volition. In epilepsy, we see the return to health take place almost as suddenly as was the attack of the disease;-in the midst of the most violent symptoms, that calm comes on which announces the termination of the attack. The heart interrupts or relaxes its wonted action, and as the common name of the disease denotes (cvv кOTTO,) the patient is struck down, blind, pale, and cold;—the heart resumes its labour, and animation is restored. In cases such as these, the cure is so simple, the steps of recovery so few and short, that we may be allowed to regard them as instances of the mere cessation of disease

In the second place, some diseases undergo a natural cure by means of the Revolutions of the Functions. As an example of this, we may take the disease of intoxication. When a person has swallowed a large quantity of ardent spirits, there follow all the symptoms produced by a narcotic poison. For a time the force of the circulation is increased, but this is soon followed by languor, delirium, and stupor, attended by nausea, vomiting, and headache. Å tendency to apoplexy is produced, and a temporary want of power over some of the voluntary, and occasionally in some of the involuntary movements of the body. In consequence of this palsy extending to the muscles of respiration, the disease of intoxication sometimes proves mortal; but in general a cure is effected by the natural revolutions of the functions of the body. We are unable to trace the processes completely by which this disease is produced and afterwards cured, but part of them is sufficiently known. It is known that the ardent spirits are carried into the circulation, for alcohol has been obtained by distillation from the blood of animals to whom it had been administered. It is also known, that mixed with the blood, it first of all excites the heart to more frequent action; and either directly, in the blood circulating through the brain, or indirectly, by operating on the nerves of the stomach, excites the brain to inordinate action, and to all the false fire and unmeaning fury of the drunkard. This is followed by congestion of the blood passing through the vessels of the brain, and this is succeeded by temporary palsy and insensibility. The method in which the body gets free of the poison is partly by its being conveyed in the blood to the kidneys, by which organs it is separated along with the urine, and thus excreted, and partly by being conveyed to the per