ACUTE BRONCHIAL CATARRH. 65 



Upon opening the thorax, if the finer bronchi be obstructed or 

 occluded by mucus, the lungs evince little or no disposition to collapse. 

 Indeed, if the contraction or obstruction have attained a very consid- 

 erable degree, the lungs bulge forcibly out of the opened thorax, so aa 

 almost to convey the impression that the chest was too small. And, in 

 point of fact, the cavity of the thorax has not sufficed to accommodate 

 the lungs without compression of the air contained in them. The in- 

 spiratory expansion of the chest has ceased with death, but the lungs 

 have not been able to diminish in a corresponding manner, because the 

 obstructed bronchi have not allowed the air to escape from the alveoli. 

 This appearance has nothing in common with emphysema, with which 

 it is frequently confounded. 



Chronic bronchial catarrh usually presents to view a more intense 

 brownish or dirty reddening of the mucous membrane. Its vessels are 

 dilated, its tissue puffed and uneven, but, at the same time, more 

 coherent and less easily torn. The mucous membrane itself is hyper- 

 trophied, and the fibrous longitudinal bands and muscular layer beneath 

 the mucous membrane are still more so. As, simultaneously with this 

 thickening, the elasticity of the mucous membrane and of the fibrous 

 coat is lost, and as the swollen, sodden bronchial muscles are, in a 

 great measure, deprived of their power of contraction, a diffuse dilata- 

 tion of the bronchi, consequent upon relaxation of the bronchial wall, 

 associates itself, in many cases, to chronic bronchial catarrh. This diffuse 

 bronchial dilatation may become so considerable that, upon section, even 

 small bronchi gape widely, exhibiting a larger calibre than the branches 

 from which they spring. 



Saccular bronchial dilatation, which is usually connected with im- 

 portant changes of structure in its surrounding pulmonary parenchyma, 

 is again to be considered while treating of diseases of the lung, as is also 

 emphysema, one of the common sequelae of chronic bronchial catarrh. 



In many cases of this disease there lies upon the mucous membrane 

 a profuse layer of yellowish puriform secretion, containing great num- 

 bers of young granulated cells, with divided nuclei, while in others it is 

 sparingly coated by a tenacious, glairy, semi-transparent substance. The 

 latter form, in which the swelling of the mucous and submucous tissues 

 is often very great, is called dry catarrh (catarrh sec). In the former 

 the copious secretion often completely fills the smaller bronchi, while in 

 the larger it is frequently mixed with air, and is frothy. 



The diffuse and follicular catarrhal ulceration which we have described 

 as occurring in the mucous membrane of the larynx seldom appears 

 upon that of the bronchi. Reinhard^ however, claims constantly to 

 have noticed it in the finest bronchi, when surrounded by tubercular de- 

 generation of the lung substance, and believes that the disintegration of 



