76 PRACTICE OF MEDICINE. 



ally occur on mucous and serous surfaces. Lombard supposes it to 

 be restricted to the cellular tissue. 



In confirmation of Dr. Carswell's statement, he has shown it in 

 the lungs formed on the secreting surface, and collected within the 

 air-cells and bronchi ; in the intestines, in the isolated and aggre- 

 gated follicles ; in the hver, in the biliary ducts and their extremi- 

 ties ; in the kidneys, in the infundibula, pelvis, and ureters ; in the 

 uterus, in the cavity of that organ and Fallopian tubes ; and in the 

 testicle, in the tubuli seminiferi, epididymis, and vas deferens. The 

 formation and subsequent diffusion of tuberculous matter is also ob- 

 served on the secreting surface of serous membranes, particularly 

 the pleura and peritoneum ; and in the numerous minute cavities of 

 the cellular tissue. The accumulation in the lacteals and lymphatics, 

 both before and after they unite to form their respective glands, is 

 frequently very considerable. 



Moi'bid appearances atid Pathology. — Tubercles in the lungs,- in 

 their earliest stage, may present themselves in three forms: 1st. 

 The common cheesy tubercle^ in yellowish friable masses, in more or 

 less rounded masses, or sometimes filling one or more of the bronchial 

 tubes. 2d. Miliary tubercles; small granules, like millet seed, bluish 

 white and semi-transparent, often found in great quantities. Some 

 pathologists consider these as the earliest stage of the yellow cheesy 

 tubercle ; others, on the contrary, believe them to be merely some 

 of the air-vesicles solidified by chronic inflammation. But certain 

 it is that they have some relation to the regular tubercle, as they are 

 found in the same person and in the same parts of the lung. 3d. 

 Tubercular infiltration ; the morbid matter being diffused uniformly 

 through a tissue, and not agglomerated in masses. 



Tubercle when deposited may lie dormant for a long time, with- 

 out exciting any particular symptoms. In very rare and favourable 

 cases, their softer particles may be absorbed ; and nothing be left 

 but the phosphate and carbonate of lime they contained, which may 

 lie quietly in the lung for a whole life. 



But, in general, tubercle, after a time, acts as a foreign body, ex- 

 cites inflammation and suppuration in the neighbouring sound parts, 

 and is expelled. 



The first visible step is a softenings which depends most likely on 

 the exudation of serum or pus by the surrounding lung, or by the 

 cellular tissue, that may be entangled in the tubercle. This increases, 

 till an abscess forms, called a vomica. 



The vomica enlarges till it bursts into a neighbouring bronchial 

 tube; and then, '\n favourable cases, after the expulsion of the tuber- 

 cular matter and pus by expectoration, the cavity may contract, 

 become smooth and cartilaginous on its inner surface, and at last be 

 obliterated, and the phthisis be cured. 



More generally, however, fresh tubercle is deposited, fresh vomicae 



