442 TUBERCULOSIS. 



sible ; that the later metamorphoses depend materially upon the 

 circumstance whether or not the nodule or node remained a tissue ; 

 and, further, that the possibility of a focus becoming callous depends 

 greatly upon its size ; and, lastly, that the solidification of the lung- 

 tissue may take place either by the formation of a capsule, or as a 

 diffuse induration, and any of these are secondary occurrences. 



A second group, found most frequently in bodies of persons 

 who died of tuberculosis, is called subacute tuberculosis. As the 

 term " subacute " is mostly a clinical expression, we might term 

 this from the disseminated or dispersed tuberculosis. Its charac- 

 teristic feature is, that new tuberculous nodules and infiltrations 

 are produced in comparatively short space of time, in consequence 

 of repeated recurrences. 



If the ulcerative destruction has not reached a high degree, 

 we find almost constantly the first form of tuberculosis, as a 

 general thing, in the apices of the lungs. Upon examining an 

 apex, not too much destroyed, we notice that, while the horny 

 and calcareous nodules remain unchanged, the capsule originally 

 inclosing a friable product has undergone marked alterations. 

 In the transverse section of the callosity constituting the cap- 

 sule we find gray, grayish-yellow, or yellow nodules, the size of 

 a poppy- or hemp-seed j the inner surface of the capsule is lined 

 'with a firmly attached, grayish-yellow, layer, resembling croup- 

 ous formations. After the removal of this, the intensely red- 

 dened capsular wall is seen dotted with the before described 

 nodules. Many of these are in a process of softening, or disin- 

 tegration into a cheesy, friable mass. 



When numerous nodules were originally formed in the cal- 

 losity, the inflammation accompanying the disintegration evi- 

 dently leads to suppuration, local mortification, and ulceration 

 of the capsule. The bordering formation of new callous tissue 

 in the inflamed lung-tissue is scanty. Here and there a new 

 rudimentary capsule may appear ; or it altogether may be absent 

 where the disease is of rapid course, and then we find lung- 

 tissue, which is eroded, uneven, sinuous, and studded with granu- 

 lations. Consequently, we meet with transitions from an acute 

 inflammation of the capsule of a tuberculous focus to its sup- 

 puration, and to a partial new formation of a thin, so-called 

 pyogenous membrane, and, finally, to an ulcerative destruction 

 of the lung-tissue. 



Simultaneously an exudation takes place into the cavity, and 

 the crumbly contents are saturated with the liquid. Should sup- 



