subject to a periodicity in their attacks, which is influenced by the season of the year and other obscure causes: there is also a certain and well-defined limit to their duration, so that we can predict with tolerable certainty the different stages of their career, and the time of their respective disappearBut, in phthisis, we meet with nothing of this kind. Consumption is equally prevalent at all seasons of the year, and under all circumstances; there is no fixed limit to its duration; no rule seems to regulate its developement; and scarcely two cases are alike in their progress. ance. Experience might, at first sight, appear somewhat to favour the idea of phthisis being a contagious disease, as examples are sufficiently common of persons, previously in robust health, having succumbed to its attacks, after the painful trial of tending a consumptive husband, or wife, or sister, or friend. But when it is remembered, that whatever lowers the physical powers, and depresses the spirits, more especially if associated with a morbid mental impression, so likely in such cases to prevail, is in itself sufficient to engender phthisis, we have a satisfactory explanation of these occurrences, and might even wonder that they are not more common. I am convinced, however, that cases originating under such circumstances, are to be looked upon as exceptions, and as bearing a very small proportion to those of an opposite kind, where, in spite of a long and uninterrupted asso ciation with the disease, no ill effect has accrued: the facility with which the former are remembered, whilst the latter are disregarded, gives them an artificial importance, and helps to exaggerate their frequency. In a thousand hospital patients, subjects of phthisis, who have fallen under my notice, and to whose cases I shall have frequent occasion to refer in illustration of other points, seven had previously lost their husbands, and four their wives, from the same disease,―a small number, when we consider the great frequency of consumption, and the large number of persons whom it must have widowed; and if we take into account the privation and other evils, inseparably attached to widowhood amongst the poor, there seems a still further reason to regard the number as a very trifling one. And it is only from instances of this kind, where there is an absence of blood-relationship, that any such observations are of value, since in the progress of the disease amongst other family connexions, it is impossible to estimate the extent of hereditary influences. I have spoken thus decidedly upon the subject of contagion, because it is one of vast social importance. Under a belief in its existence, nurses, and other attendants upon the consumptive, are liable to become depressed in spirits, and to fall the ready victims, either of the same disease, or of any other to which they may have a tendency. But the evil does not cease here. The invalid ne cessarily suffers, in consequence of the apprehension of those around him causing the exercise of a certain carefulness, which unavoidably leads to the neglect of Christian kindness, and this, too, at a time when the attention of friends is often calculated to be the chief, or perhaps the only, solace in his affliction. CHAP. II. MODE OF ORIGIN, GENERAL CHARACTERS, AND MINUTE STRUCTURE OF TUBERCLE. by TUBERCULAR matter is formed in two ways: a gradual and uninflammatory process of separation from the blood; (2) by inflammatory action, ending in a morbid scrofulous secretion, instead of a healthy or fibrinous one. The first of these is by far the most common-in fact, the ordinary mode of its production, and may be illustrated by any of the numerous cases where phthisis begins slowly, and advances insidiously, unattended at its commencement by any marked thoracic symptoms; the second is comparatively rare, and is to be seen in those cases where pneumonia, pleuropneumonia, or bronchitis, either from neglect or a consumptive predisposition, become obstinate and chronic, and finally pass into confirmed phthisis. Some pathologists have advocated its necessarily inflammatory origin; but this is at once negatived by the fact, that not only are the signs of pneumonia of rare occurrence during the early periods of phthisis, but on examining the pulmonary structure which surrounds tubercle of recent formation, there is seldom any appearance of inflammation; the lung, although more or less congested, is almost invariably crepitant, and capable of floating upon water. It is true that, after tubercle has existed some little time, the parts immediately around it are often hard and thickened; but this is the result either of secondary inflammation, or of a process designed with a special object, to which I shall hereafter have occasion to refer. Some writers have considered tubercle as a peculiar transformation of infiltrated blood; some, as derived from hydatids; whilst others have called it inspissated pus: but such views may be passed over as merely speculative, if, indeed, they have not been actually disproved. The majority of the medical profession are now agreed in regarding it simply as a lowly-vitalized material, unfit for the construction of new tissues, and, consequently, as forming an extraneous substance, in whatever organ it may ultimately be deposited. It makes its appearance in the form of whitishgrey bodies, differing in number and distribution, and long known under the terms miliary tubercle, or grey granulations. These vary in size, from that of a pin's head, to that of a small pea, but occasionally they are so minute, as scarcely to be discernible by the naked eye, and, now and then, they assume a much larger size; they are usually hard, firm, and cartilaginous-looking, but, in a few cases, I have found them soft, and easily broken between the fingers. They seem to have some |