mind), good may be done by all means which tend to moderate the symptoms, restore right secretions, and sustain the powers of life. But until the proportion of mortality is distinctly abated under some given plan of treatment, and this effect well attested by comparison with other places where different methods, or no methods at all, have been pursued, the conclusion will remain, that no real antidote has yet been discovered; and that the cases interpreted as cures derive this character from causes which we neither recognise nor can command.

If the disease should still continue in the world, and a remedy, justly so called, be happily discovered hereafter, it will probably be of the nature of a specific antidote to the action of the virus on the blood. I hazard this opinion, looking to the singular importance of this action in the pathology of Cholera; to the promise which animal chemistry gives of new methods of altering the state of the blood; and to the actual results obtained by means expressly applied to the object in question. I allude to the treatment by saline injections into the veins; which, though not yet thoroughly established by experience, has nevertheless in many cases been found to possess singular power in checking the progress of collapse; and approaches nearer, perhaps, to a successful issue than any other method yet employed. Still it is only an approach; and the problem yet remains to be overcome, either by accident, or the better fortune of future experiment. Casualty may perchance serve us better here than reason; but we are bound to follow the latter as far we can.

The best contingency, next to that of a specific remedy, seems to be the discovery of means capable of sustaining or restoring the nervous power of the vital organs, so rapidly and deeply affected by the disease.

Any agent equal to fulfil

such purpose must presumably be both simple and powerful:

whether electricity, in any form of its action, may be capable of this, is a question not yet fully answered. Speaking generally of the treatment of Cholera, I certainly do not believe that an efficient means of cure will ever be attained by dealing with the symptoms in detail. The magnitude of the disease, and intensity of its cause, are beyond this means of reaching them; and it is probably only in the milder cases that any such result can thus be obtained. After all, is it just to speak of our ignorance of a remedy for Cholera as a peculiarity of this disorder? Have we any more certain or specific cure for other contagious or epidemic diseases, unless dignifying with this name that mitigation of symptoms, and prevention of particular mischiefs, which alone come within the rule of safe practice in most of these cases? The instance is one among many, where long familiarity with certain disorders, or their milder character, disguise the connexion they have with other diseases, less known and of greater virulence. The preventive remedy discovered for small-pox is an eminent, though partial, exception to the remark; and an indication, at the same time, of what may yet be possible in other diseases where a specific virus is present the cause of malady to the individual, and the means of its dissemination to others. Whatever the nature of the virus of Cholera, the contingency of discovery is the same here as elsewhere: and if, like the small-pox, it is to be considered a new form of disease engendered in the world, and destined to remain as a wandering pestilence here, the attainment of this object is manifestly most important to human welfare.

These remarks, however, have no peculiar application to the hypothesis before us. This has now been discussed in as much detail as a speculation merits to be in which direct proof is wanting; and for which a main argument is the inadequacy of all other hypotheses to explain the facts. I

have not noticed the further objection which may be urged against it, that, if well-founded, its application would not be limited to Cholera, but must of necessity extend to certain other contagious or epidemic diseases, (and especially to the epidemic influenzas) of which the essential conditions are so far the same, as to warrant the belief of a similar, though not identical, cause. The justness of the inference can in no way be denied; nor the extent to which it would carry speculation in advance of actual knowledge. This in truth is the wider question, serving as title to the present chapter; how far, and in what manner, the animal life of one species may become a source of disease to another, and the case of Cholera was taken merely as furnishing the most various and singular illustration of the argument.

The general question is one still open to research; - sanctioned in its object by our ignorance of other causes for these genera of disease; — affording some curious presumptions where certainty may be unattainable; — and involving a topic than which none is more remarkable, viz., the origin and progress of those disorders, which, if not newly generated, have first appeared in our parts of the world within the period of modern record; and become endemic, where there is no authentic trace left by history of their prior existence.

599

CHAP. XXXIV.

ON THE PRESENT STATE OF INQUIRY INTO THE NERVOUS

SYSTEM.

D'ALEMBERT has well designated the space which lies between geometry and metaphysics, "L'abîme des incertitudes et le théâtre des découvertes." A remarkable part of this wide intellectual domain is that occupied by the science of the nervous functions; forming, in the present state of our knowledge, a sort of neutral ground between the sciences which deal with matter in its various forms, and those which have relation to the functions of animal life and mental existence. It is this vicinity to the region of metaphysics which has given to the subject its peculiar ambiguities. Language here, labours vainly to follow the suggestions of thought or consciousness; and the discussion has been endlessly perplexed by the effort of philosophers of all ages to give phraseology to their doctrines, without any covenanted understanding of the ideas they involve.

The deep interest now felt in this branch of physiology, and the active and refined inquiry directed to it, may warrant some observations on the subject, even though not adding to the facts already known. It is one of the cases in science where a nearer approach to truth is sometimes gained by recasting the order of facts, and using them in new combination. In the following remarks I shall merely touch upon some parts of this wide topic; putting much interrogatively, as best befits what is still so uncertain and obscure.

* Those who desire to learn the actual state of knowledge in this complicated inquiry, will do well to refer to a series of most able articles in

Language, indeed, must not alone be charged with the difficulties which belong to the inquiry. Our progress is at every moment stopt; on the one side, by the intricate and subtle organisation it is needful to decipher; on the other, by those more insuperable bounds which, in the very constitution of the human mind, seem placed to prevent too close a contemplation of its own workings; or even of the manner of relation to the material instruments through which it acts. It may be that some men, by higher capacity of reason, whether invested in language or not;—or by greater power of concentration, if this term better express the act of mind;

do really approach nearer than others to the comprehension of these great functions of our nature. But every such difference is trifling in relation to the undiscovered and impassable space that lies beyond; and the highest attainment is that which can best define the boundary of research, and labour for truth and knowledge within it.

A question illustrating these remarks, and which stands indeed foremost in the inquiry, is that regarding the separate existence and attributes of the nervous power. Whatever opprobrium has been thrown, justly or unjustly, upon this term, it is certain that we cannot dispense with some phrase equivalent to it, in reasoning on the phenomena of animal life. At every step we are obliged to admit the conception of the fact thus expressed; and however inadequate our present means to determine its nature, and relations to the mental and physical parts of our being, we can no more deny reality to such a power, than we can to the effects of which it is the obvious source. Other terms,

energy, agency,

the British and Foreign Medical Review; embracing its relations to all other branches of physiology, as well as to the higher and more general principles of inductive science.