522 GENERAL ANATOMY. 



brane of a new formation, more or less distinct, more or less 

 vascular, according to its age; the surrounding cellular tissue, 

 inflamed and very vascular, has lost its permeability by the 

 interstitial deposition of organizable matter. 



The serous membranes, when they suppurate, present ana- 

 logous changes; they become very vascular and take at length 

 the appearance of mucous membranes. 



822. Boerhaave attributed the origin of pus to the meeting 

 of inflamed organs; Pringle and Gaber attributed it to a change 

 in the serum of the blood; these two opinions, differently mo- 

 dified and combined, have been for a long time and generally 

 adopted. 



The idea that pus is formed in vessels, and that it departs 

 from^them by a secretory action of these organs, was first in- 

 dicated by Dr. Sympson, then by Dehaen, and afterwards-by 

 Dr. Morgan, of. Philadelphia. Hunter and Brugmans have 

 embraced and developed this doctrine, which is now general- 

 ly adopted. 



Suppuration is a morbid secretion. This secretion is al- 

 ways preceded and determined by inflammation; but the in- 

 flammation is more or less evident. Dehaen himself, who 

 expressly admits suppuration without previous inflammation, 

 evidently means to speak only of inflammation with ulcera- 

 tion: in fact, we now well know, what he then announced, 

 that suppuration might take place upon surfaces without altera- 

 tion; he notices, in cases of suppuration without inflammation, 

 plastic productions and adherences which depend, as we know, 

 on inflammation. 



In scrofulous constitutions suppuration is often preceded 

 only by a chronic and latent inflammation, but which does not 

 the less exist, although it is obscure. 



823. Suppuration, when it exists for a long time, and when 

 it takes place on a large surface, becomes, by its association 

 with the functions, an important secretion; thus we should 

 not lightly establish or suppress a suppuration. 



Pus is sometimes the vehicle of virus introduced into the 

 organization; it is considered also, in some cases, as the vehi- 

 cle of the cause of maladies eliminated by the organization. 



