duced might readily heal up, as it does in the case of a cynanche tonsillaris; and therefore should not produce a phthisis.

871. Further, the catarrh, as purely the effect of cold, is generally a mild disease, as well as of short duration; and of the numerous instances of it, there are at most but very few cases which can be said to have ended in phthisis. In all those cases in which this seems to have happened, it is to me probable, that the persons affected were peculiarly predisposed to phthisis. And the beginning of phthisis so often resembles a catarrh, that the former may have been mistaken for the latter. Besides, to increase the fallacy, it often happens, that the application of cold, which is the most frequent cause of catarrh, is also frequently the exciting cause of the cough, which proves the begin. ning of phthisis.

is

872. It is to me therefore probable that a catarrh very seldom the foundation of phthisis; but I would not positively assert, that it never is so; for it is possible, that the cases of a more violent catarrh may have joined with them a pneumonic affection, which may end in a suppuration; or it may happen, that a long continued catarrh, by the violent agitation of the lungs in coughing, will produce some of those tubercles which are presently to be mentioned as the most frequent cause of phthisis.

873. It must be particularly observed here, that nothing said in 872, should allow us to neglect any appearance of catarrh, as is too frequently done; for it may be either the beginning of a phthisis which is mistaken for a genuine catarrh, or that even as a catarrah continuing long, it may produce a phthisis, as in 872.

874. Many physicians have supposed an acrimony of the fluids eroding some of the vessels of the lungs, to be a frequent cause of ulceration and phthisis. But this appears to me to be a mere supposition: for in any of the instances of the production of phthisis which I have seen, there was no evidence of any acrimony of the blood capable of eroding the vessels. It is true, indeed, that in many cases an acrimony subsisting in some part of the fluids, is the cause of the disease; but it is at the same time probable, that this acrimony operates by producing tubercles, rather than by any direct

erosion.

875. It has been mentioned in 863, that an asthma may be considered as one of the causes of phthisis; and by asthma I mean, that species of it which has been commonly named the Spasmodic. This disease frequently subsists very long without producing any other, and may have its own pecuculiar fatal termination, as shall be explained hereafter. But I have seen it frequently end in phthisis,

and in such cases I suppose it to operate in the manner above alleged of catarrh, that is, by producing tubercles, and their consequences, which shall be presently mentioned.

876. I come now to consider the fifth head of the causes of phthisis, and which I apprehend to be the most frequent of any. This I have said, in general, to be tubercles; by which term are meant, certain small tumours, which have the appearance of indurated glands. Dissections have frequently shewn such tubercles formed in the lungs; and although at first indolent, yet at length they become inflamed, and are thereby changed into little abscesses, or vomica, which breaking, and pouring their matter into the bronchiæ, give a purulent expectoration, and thus lay the foundation of phthisis.

877. Though the matter expectorated upon these occasions has the appearance of pus, it is seldom that of a laudable kind; and, as the ulcers do not readily heal, but are attended with a hectic fever, for the most part ending fatally, I presume that the matter of the ulcers is imbued with a peculiarly noxious acrimony, which prevents their healing, and produces a phthisis in all its circumstances, as mentioned above.

878. It is very probable, that the acrimony

which thus discovers itself in the ulcers, existed before, and produced the tubercles themselves; and it is to this acrimony that we must trace up the cause of the phthisis following these tubercles. This acrimony is probably, in different cases, of different kinds; and it will not be easy to determine its varieties: but to a certain length I shall attempt it.

879. In one case, and that too a very frequent one, of phthisis, it appears, that the noxious acrimony is of the same kind with that which prevails in the scrofula. This may be concluded from observing, that a phthisis, at its usual periods, frequently attacks persons born of scrofulous parents; that is, of parents who had been affected with scrofula in their younger years; that very often, when the phthisis appears, there occur at the same time some lymphatic tumours in the external parts; and very often I have found the tabes mesenterica, which is a scrofulous affection, joined with the phthisis pulmonalis. To all this I would add, that, even when no scrofulous affection has either manifestly preceded or accompanied a phthisis, this last however most commonly affects persons of a habit resembling the scrofulous; that is, persons of a sanguine, or of a sanguineo-melancholic temperament, who have very fine skins, rosy complexions, large veins, soft flesh, and thick upper lip and further, that in such persons the phthisis

comes on in the same manner that it does in persons having tubercles, as shall be immediately explained.

880. Another species of acrimony producing tubercles of the lungs, and thereby phthisis, may be said to be the exanthematic. It is well known, that the small-pox sometimes, and more frequently the measles, lay the foundation of phthisis. It is probable also, that other exanthemata have the same effect; and from the phenomena of the disease, and the dissections of persons who have died of it, it is probable, that all the exanthemata may occasion a phthisis, by affording a matter which in the first place produces tubercles.

881. Another acrimony, which seems sometimes to produce phthisis, is the siphylitic; but whether such an acrimony produces phthisis in any other persons than the previously disposed, does not appear to me certain.

882. What other species of acrimony, such as from scurvy, from pus absorbed from other parts of the body, from suppressed eruptions, or from other sources, may also produce tubercles and phthisis, I cannot now decide, but must leave to be determined by those who have had experience of such cases.

883. There is one peculiar case of phthisis, which