104 



PRODUCTS, ADVENTITIOUS. 



structure, and so it commonly is. But in 

 some instances, in addition to granular matter 

 lying in a structureless substance, remnants of 

 cells may be detected, and, more rarely still, 

 nucleated cells of unbroken outline, some 

 larger, others smaller than the red blood- 

 corpuscle. Epithelium cells are often acci- 

 dentally present, as also oil globules. 



That the main element of this material is of 

 protein-basis may be inferred from its general 

 properties. Buzzorini* gives its composition 

 from direct analysis as follows, fibrin, phos- 

 phate of lime, lactate and hydrochlorate of 

 soda, and traces of other salts of the blood. 

 Under the microscope acetic acid renders the 

 basis more or less transparent ; its effect on 

 the cells seems to vary. 



We have seen matter of similar character in 

 the mesenteric glands ; and we cannot affirm 

 that the intestine and these glands are its sole 

 seats, not having looked for it in other parts 

 of the body of typhoid patients. 



2. TUBERCULOUS DEPOSIT, OR TUBERCLE. 



Tubercle, when in that condition that its 

 properties are most clearly marked, and when 

 at that period of its development that no 

 dissentient opinions are held as to its nature, 

 possesses the following characters. It is an 

 opaque substance of yellowish colour; suffi- 

 ciently firm yet friable, of little tenacity, and 

 resembling cheese very nearly in point of 

 consistence ; inelastic ; without particular 

 smell ; accumulated in small masses varying 

 in size from a pin's head to a hen's egg, of 

 homogeneous aspect all over their divided 

 surface ; exhibiting no vessels ; insoluble in 

 water, and if mixed therewith quickly subsid- 

 ing to the bottom. And these are the pro- 

 perties of a material which, in respect of its 

 physiology, is characterized by its tendency 

 to become soft after it has existed for a 

 variable period in the condition of firmness, 

 and to induce various changes in the natural 

 textures with which it is connected, changes 

 eventually effecting its own complete disin- 

 tegration and elimination. 



Nothing can be more true than that tubercle 

 is homogeneous ; but this may or may not be 

 true of a tubercle. A tubercle of the brain is 

 perfectly so ; each particle is the counterpart 

 of all others composing it, and for the simple 

 reason that the natural structure, wherein the 

 new matter has found a nidus, has been pushed 

 aside in proportion as that matter has accu- 

 mulated, A tubercle of the lung, again, may 

 also upon rough inspection appear homoge- 

 neous ; but if closely scrutinized with the 

 naked eye, or, better, with a lens, it will be 

 found that the section of the little body is 

 marked by lines of a different tint and aspect 

 from its general substance. This arises from 

 the enclosure of some of the tissue of the 

 organ by the accumulating tuberculous sub- 

 stance. 



Tubercle may be deposited in isolated 

 masses, or, it is said, be infiltrated through 

 the stroma of the various tissues. ( 1 .) When 



* Der Typhus, 1836, S. 87. 



occurring in masses it is usually of tuberiform 

 shape, and the mass has sprung either from a 

 single centre of formation, or from the con- 

 crescence of several smaller tubercles formed 

 in the close vicinity of each other. It has 

 long been a subject of dispute whether tube- 

 riform tubercle occurs in the encysted form. 

 Laennec held the affirmative ; and M. Louis 

 follows on the same side. Dr. Carswell 

 "feels perfectly satisfied that the term en- 

 cysted, whether applied to pulmonary tubercle 

 or to tubercle in any other organ, is almost 

 always incorrect. In the lungs encysted tu- 

 bercle is a deception, the distended walls of 

 the air-cells having in all probability, in almost 

 every case, been taken for cysts. In like 

 manner the dilated bulbous extremities of the 

 biliary system have been described as cysts of 

 the liver containing tuberculous matter."* The 

 evidence furnished by Laennec and M. Louis 

 is defective ; the latter observer never saw the 

 presumed appearance in the lung but once, and 

 no description is recorded from which the accu- 

 racy of the explanation offered may be ascer- 

 tained. t On the other hand, Dr. Carswell's 

 objection turns altogether upon his special 

 notions concerning the almost limitation of 

 tubercle to the mucous surfaces. We have 

 ourselves never seen encysted tubercle in any 

 structure of the body, if by the term be under- 

 stood tubercle contained within a cyst, which 

 has acted as its formative organ. But we have 

 seen in very rare instances in the lung, and, 

 comparatively speaking, somewhat more fre- 

 quently in bone, tuberculous matter surrounded 

 by a more or less complete membrane, strongly 

 assimilable in properties to the pyogenic mem- 

 brane of abscesses, and, like it, obviously 

 formed consecutively to some at least of the 

 matter it invested. Such we believe to be the 

 key to the comprehension of " encysted tu- 

 bercle," especially taken in conjunction with 

 the fact that true abscesses in the lung have not 

 unfrequently been mistaken for tuberculous 

 accumulations. To the class of secondary 

 cysts is also to be referred that species of 

 membranous investment occasionally formed 

 round tuberculous matter while undergoing a 

 process of inspissation. 



The tuberiform shape is so common in tu- 

 berculous masses that its cause has been made 

 matter of inquiry. By some persons pre- 

 sumed to depend on a moulding faculty in- 

 trinsic in the tuberculous substance (an obvi- 

 ously absurd notion), it has been referred by 

 Schroeder van der Kolk and Dr. Carswell to 

 the influence of the surrounding parts. The 

 latter observer well shows that, in point of 

 fact, this shape is less common than has been 

 maintained, and scarcely occurs except in the 

 brain and cellular membrane, and under cer- 

 tain circumstances in the lung. Stratiform 

 deposition is that occurring on. serous sur- 

 faces in layers ; ramiform, that observed in the 

 bronchi and biliary system. 



* Illustrations of the Elementary Forms of Dis- 

 ease, Fascic. Tubercle. 



t Louis on Phthisis, "Walshe's Transl. Reprint, 

 p. 426. 



