is less inclined to soften and break down. The seat of tubercle in the vast majority of cases is on the exterior of the vessels, but in their immediate neighborhood; its blastema is a true exudation, but, inasmuch as it coagulates with great rapidity, it is not able to penetrate for any distance through the substance of a non-vascularized tissue. Hence, we

Section of a gray granulation in the lung after the addition of acetic acid, showing the pulmonary air-vesicles filled with tubercle corpuscles. 250 diameters linear.

do not find tubercle in cartilage. In very rare instances, coagula of tuberculous character have been seen within the vessels; but these, no doubt, underwent a morbid alteration after being formed; and there is not the least evidence to show that anything resembling tuberculous matter has even been detected in the blood. The microscope can discover nothing peculiar in the blood of phthisical patients, nor has chemistry detected any characteristic alteration in its protein compounds, which we might reasonably expect to find primarily affected. The exudation of tubercle-blastema may take place most gradually and imperceptibly, with scarce a trace of constitutional disturbance, or it may occur in a rapid, tumultuous manner, with all the symptoms of an acute illness; between these extremes the most various grades are observed. The more rapid the deposition of tubercle, the more is it associated with hyperemia and inflammation. In fact, though the production of tubercle be quite independent of inflammation, and though inflammation, in the great majority of cases, is only secondary, and excited by it, as a cause of irritation, yet, when set up, it has a powerful effect in hurrying the exudation of tubercle, and that of such a kind as tends to rapid softening and decay. Commonly, the gray tubercle is the first to appear; sometimes, however, the yellow, in the miliary dispersed form; afterwards, as the dyscrasia increases, the exudation consists of yellow tubercle mingled with the gray; and, finally, of yellow tubercle alone. Tubercle may be deposited, we believe, in extravasations of blood, or, at least, its blastema may be mingled with blood; the changes which the latter undergoes, suggest to Rokitansky the

name of pigmentary tubercle, as distinguishing it from the more common varieties. Melanic matter, however, is often found, in small quantity, in the latter also. The following remarks are of much interest and importance relative to the coexistence of tuberculous disease with other affections.

Fig. 43.

Corpuscles mixed with pig

tubercle taken from the peritoneum. a. Irregular masses

of black matter, which may be broken down into (b) gra

nular and molecular matter. 250 diameters linear.

Cystic growths are not often associated with tubercle, and the same is true of cancerous; when the latter are present together with tubercle, they are, in most cases, of secondary origin to it. Rokitansky contrasts the frequency of tuberculization of the lungs with the rarity of pulmonary cancer; the frequency of ovarian, gastric, and mentary matter, in a small rectal cancer, with the rarity of tuberculous deposit in these parts. These and other facts indicate that the one morbid process tends to exclude the other. Typhus and the exanthemata, he states, do not commonly attack the tuberculous, but they are very apt to be followed by tuberculous disease. Sufferers from intermittent fever, goîtrous disease, and rachitis, seem to be, pro tanto, less liable to tuberculous affection. The non-coexistence of aneurismal and tuberculous disease depends, in Rokitansky's opinion, on the exhaustion of the fibrinous constituent of the blood, by the deposits taking place on the inner surface of the sac. An especial immunity against tubercle is afforded by an abnormally venous condition of the blood, from whatever cause this may come to pass. Congenital malformations of the heart or great blood vessels; morbid alterations of the same; deformities of the chest, producing contraction of its cavity; annihilation of the function of one lung by pleuritic effusion; abdominal growths, preventing the free descent of the diaphragm; chronic pulmonary catarrh; emphysema and bronchial dilatation, have all been observed as exercising an unquestionable counter influence against the development of tubercle; and in all these conditions the free oxygenation of the blood is more or less interfered with. The undoubted effect of pregnancy in delaying the advance of tuberculous disease of the lungs, is explained by Rokitansky on the same principle of impeded, and consequently imperfect respiration, inducing a venous condition of blood; and he refers to the great production of fibrin, which takes place after parturition, as confirmatory of this view-tubercle being regarded as a fibriniform product. Respecting the identity of tuberculous and scrofulous matter, there can be no doubt. They have the same elementary composition, they undergo the same changes, they are produced in the same way, and produce the same effects on the tissues in which they are deposited. Generally, it may be said, that the deposit in the absorbent glands and bones passes for scrofulous; that in the lungs or brain, for tuberculous matter-both being essentially what we have described as yellow tubercle. The name seems to depend almost entirely upon the form. In

Fig. 44.

adults, tubercle is found in the various organs in about the following scale of frequency: Lungs, intestinal canal, lymphatic glands (especially the abdominal and bronchial), larynx, serous membranes, brain, spleen, kidneys, liver, bones, and periosteum, uterus and Fallopian tubes, testicles (with the prostate gland and vesiculæ seminales), spinal cord, voluntary muscles. In children, Rokitansky states, the lymphatic glands and spleen are most often affected, then the lungs, and after these the brain, &c. MM. Rilliet and Barthez assign, as in adults, the primary place to pulmonary tubercle. According to them, however, the lungs are not so invariably affected as M. Louis's well-known law declares them to be in adults; as, in forty-seven out of three hundred and twelve instances, they were exempt, while tuberculous deposit was found in other organs. It is to be observed that the above scale of frequency of the occurrence of tubercle in adults does not express correctly the

Fig. 45.

Fig. 46.

Scrofulous pus-a large glomerulus is shown, and

some oil drops.

Scrofulous pus from a lymphatic
gland. 250 diameters linear.

different tendency of the various organs to primary tuberculosis. Rokitansky places in this respect the lungs and lymphatic glands first, then

Fig. 47.

the urinary organs, the bones, the testicles, &c.; while the intestines, the larynx, the spleen, and the liver, occupy the lower part of the scale. The question as to how far, and in what way tuberculous disease is curable, is of course of the greatest interest. As an exudation, it seems credible that tubercle should liquefy and undergo absorption; but it has been very generally doubted whether this ever actually occurs. Dr. Walshe, whose authority is great on this point, believes that absorption, under favorable circumstances, may take place, but acknowledges it to be a rare event. Probably the most favorable result that can generally be expected, after tubercle is once deposited, is either that it should cornufy simply without having undergone softening, or that after this change it should cretify. After tubercle in any quantity has softened, and a cavity been formed from which the tubercular detritus is afterwards eliminated, a cure may still take place; but it is a much rarer occurrence than in the two former cases, and perhaps never attains to the complete closure and cicatrization of the cavity. This, at least, applies to the lungs; in other parts, there is no doubt that a tuberculous ulcer may heal up and cicatrize. The production of tuber

cle sometimes takes place, as observed above, with very great rapidity, constituting what is termed acute tuberculosis. It is remarkable that the symptoms in this condition very closely resemble those of typhus fever (v. case in Dr. Walshe's work on Diseases of the Lungs and Heart, p. 409). The tubercle is of the gray miliary kind, is widely and uniformly scattered throughout the lungs, and is often deposited in other parts also.

As a sequel to the foregoing account of tubercle, we may describe here a somewhat analogous deposit, which is not very unfrequently found in the organs of those who are the subjects of general cachexia. It appears as a solid blastematous mass, infiltrated among the tissues of a part; semitransparent, or verging on a whitish opacity-presenting, under the microscope, an amorphous, flaky basis-substance, together with scanty nuclei. It is commonly deposited in a part in considerable quantity, and gives rise to the appearance of hypertrophy, though at the same time the natural elements of the tissue are compressed and atrophied, often to a great extent. An organ thus affected is bloodless, breaks with a sharp fracture, and strongly resembles bacon in appearance, from whence the term "bacony" is applied to the deposit by German writers.

The formation of this matter is not peculiar to the scrofulous diathesis, but it is observed in those who have become cachectic from any cause; as from the abuse of mercury, inveterate syphilis, habitual intermittents, or any severe drain upon the system. Rokitansky calls the deposit "albuminous raw blastema," and believes it to proceed from an undue quantity of albumen being present in the blood.

With respect to the real nature of the tuberculous crasis, we have scarce any exact knowledge. It is evidently a special dyscrasia, intimately connected, as we know, with causes of debility, and leading to the effusion of a matter, which shows only the feeblest traces of organization. This matter in many respects comports itself very differently to fibrin; so much so, that the one might almost be regarded as the antithesis of the other-supplanting it in the process of effusion, or itself replaced by it. Rokitansky, however, shows some weighty reasons for regarding tubercle as a modification of fibrin; and after a most interesting discussion, to which we would particularly refer (v. p. 522, German edition), concludes that "the arterial character-arterial elaboration of the fibrin-constitutes, above all, the cardinal feature of the tuberculous crasis." He also points out how, in consequence of the alteration of the nature of the fibrin, tubercle is continually deposited, even when the blood is very deficient in that constituent. All the fibrin that is formed is soon affected by the peculiar dyscrasia, and is thrown out in the form of tubercle. The rapid coagulation of tubercle-blastema, which must be effused in a fluid form, its tendency, when coagulated, to soften-its formation being favored by active arterialization, and prevented by a venous condition of the blood-are circumstances which indicate a real affinity between tubercle and fibrin. When we further reflect that various debilitating causes are found to increase the quantity of fibrin, and also that the same are potent in causing the production of tubercle,

we gain further evidence to the same effect. No doubt, however, even before that peculiar modification of the fibrin has occurred, which leads to its excretion in the form of tubercle, a special impress is, at least in many cases, stamped upon the system, which betrays to the instructed eye the future evil. The tendency and proclivity to disease is there, it may be, long before its actual development. This unexplained proclivity it is which constitutes the scrofulous diathesis.

A condition of the blood, characterized by deficiency in fibrin, excess of albumen, and for the most part also of blood-globules, is termed by Rokitansky venosity, or albuminosis. Simon designates it hypinosis, in contrast to hyperinosis, which implies an excess of fibrin. Rokitansky describes under this head several crases, in which the blood partakes of the hypinotic character; but we shall do no more than enumerate them, as we think he ascribes far too much to the apparent qualities of the blood, and does not take sufficient count of the unseen but essential derangements: "Hypinotic blood is in general a thick, sticky, dark red fluid; contains no coagula, or only small, soft, sticky, gelatinous ones, which include much cruor." It is apt, under peculiar circumstances, to undergo various changes, such as septic destruction of the albumen, in which case necræmia takes place; or a croupo-fibrinous or pyæmic condition may supervene; or a tendency to the effusion of acid fluids and acute softening of tissues. Dark hypostatic stains, speedy putrefaction, transitory rigor mortis, a lax state of the solids, are observed in the bodies of those who die with this condition of blood.

The subordinate hypinotic cases are (1) plethora; (2) the typhous; (3) the exanthematic; (4) that existing in certain diseases of the nervous system; (5) drunkard's dyscrasia; (6) cancerous dyscrasia.

We may mention, with regard to the drunkard's dyscrasia, that, when chronic, it presents a remarkable dark color, and inspissation of the blood, with excessive quantity of oil. Fat is formed abundantly in the subcutaneous tissue, and in other parts. The liver, the muscles, and even the bones are either encroached on by the fat, or undergo some degree of fatty degeneration. The cerebral membranes are apt to become thickened, the brain itself to be atrophied. Chronic fluxes, from the mucous membranes, especially the bronchial and intestinal, are very common. The crasis often undergoes change to the croupo-fibrinous.

We would recommend the doctrine of crases of the blood to the careful thought of our readers. No doubt it may easily be carried too far; but we think cases will often present themselves, in which an apparent inflammation and manifest exudation will be better explained and managed by the ideas which this doctrine suggests, than by the most vigorous anti-phlogistic proceeding.