as well as either to render the tubercle itself innocuous to, or to favour its elimination from, those structures in which it has been already deposited. To this end, it is necessary, first, to be acquainted with the nature of the disease; secondly, to be able to detect it under all its varied phases; and, thirdly, to be familiar with the different means which experience has shown to be the most efficacious in remedying it. The subject, therefore, naturally arranges itself into three divisions: first, the Nature -second, the Symptoms-third, the Treatment of the disease; each of which will require a separate consideration. PART I. THE NATURE OF CONSUMPTION. CHAP. I. DEFINITION OF PHTHISIS; DISTINCTION BETWEEN IT AND TUBERCLE-CONSUMPTION A NON-CONTAGIOUS DISEASE. THE proper relationship of phthisis to tubercle has, perhaps, scarcely received the attention which it deserves: we have been too much accustomed to consider them as inseparable, and, indeed, to use the terms as different modes of expressing the same condition. But it is necessary, both on scientific and practical grounds, to draw a broad distinction between them, since the one may exist without the other, and even continue to do so for a long period. At the first onset of consumption, the lungs are not necessarily tubercular. It is true that, before the pulmonary structures have become implicated, we often fail in detecting the disease, the premonitory symptoms having been too short or obscure to attract observation; in a large number of cases, however, these are sufficiently obvious, and, probably, in none are they entirely wanting. The term phthisis is alone applicable to that peculiar morbid condition which involves, amongst other consequences, a tubercular state of some of the internal organs; whilst tubercle expresses the effect of such a condition ;—the one being related to the other in exactly the same way that saccharine matter is to diabetes, and lithate of soda to gout. But it is not only at the beginning of consumption that this distinction is obvious and imperative; for, during the whole course of the disease, phthisis and tubercle still hold the same relative position, continuing to each other as cause and effect. The truly consumptive symptoms are never dependent upon the amount or even the condition of the tubercular deposit, but upon the degree of functional disorder under which it has been produced or altered; and of this no better proof can be given, than the fact, that cases often present themselves, in which, although the tubercle is as yet unsoftened, consumption is more marked, and life apparently more threatened, than in other cases, where the pulmonary structures are broken down into cavities. The one unquestionably reacts upon and aggravates the other; yet it is, in truth, the phthisis, and not the tubercle, which destroys life; the latter would, in most instances, either be expelled, or become innocuous, could we but apply a timely and effective remedy to the other. It is essential to the proper treatment of consumption, that the disease, from first to last, should be regarded as a general, and not a local one; and it is owing to this not having been attended to, but to the pulmonary tubercles having been considered as the first cause of derangement, and the source of all the subsequent symptoms, that many practical errors have been committed, and a number of different expedients-amounting even to formidable operations-fruitlessly resorted to, for the treatment of the local or pulmonary affection. Phthisis may be either inherited or acquired; but, of its intimate nature, our knowledge is very limited. The same remark, however, is applicable, and perhaps with equal truth, to other affections also. In consumption, as in many other maladies, we are permitted to recognise the disease only in its effects: for example, we can examine tubercle, and ascertain its chemical and microscopical characters, as easily as we can the lithate of soda, or diabetic sugar; but of the causes from which these may spring, which are, in fact, the diseases themselves, we are completely ignorant. It is evident that, in all such cases, there must be something which constitutes the malady; but it would be vain to search after it—it has no individuality—it is a process which, like many others, is so subtle and far removed even from our conceptions, that it seems destined to remain for ever beyond our reach; we are allowed to do nothing more than study its laws, and, in some measure, regulate its actions. Many persons are inclined to the belief that phthisis originates in a morbid and material poison, as distinct as that of typhus or variola, and possessing the like power of communicability; but such a conclusion appears to me untenable, being opposed both to argument on analogy and simple experience. In classifying diseases in reference to their origin, they would be found to arrange themselves into two divisions; namely, first, those which arise from poisons introduced from without; and, second, those depending upon an unhealthy process springing up within. To the former class belong primary fevers, whether continued, intermitting, remitting, or exanthematous - all epidemic and endemic disorders — syphilis and every disease capable of being extended by inoculation. In the latter class, may be placed gout, phthisis, scrofula, malignant diseases, diabetes, besides other morbid conditions resulting from a derangement of the nutritive functions. The former class, with but few exceptions, may be propagated by means of their own morbid products; the latter have the common property of being attended by peculiar secretions, innocuous to all individuals but those producing them. In the one, hereditary influences are almost inoperative, or, at most, are very remotely connected with their production; but, in the other, the opposite is usually the case, of which consumption affords a striking illustration. Most diseases, arising from specific poisons, are |