ABNORMAL FORMS OF THE NUTRITIVE PROCESS. 461 



the surrounding tissue, or upon a neighbouring surface. This deposition of 

 the Fibrinous element, possessing a high degree of plasticity, and capable of 

 spontaneously passing into simple forms of tissue (which may be gradually 

 replaced by higher forms, when penetrated by vessels from the surrounding 

 parts), may be regarded as the first characteristic result of Inflammation, ft 

 is by the deposition, and subsequent organization, of plastic matter in the sub- 

 stance of organs, that their tissues become consolidated ; and by its deposition 

 and subsequent organization upon their free surfaces, that false membranes and 

 adhesions are formed. It appears probable, from the recent inquiries of Mr. 

 Robinson,* that this deposition may be attributed to physical causes. It is well 

 known, that simple Congestion will occasion transudation of the serous portion 

 of the Blood ; and if the return of the Blood by the veins of a part be com- 

 pletely prevented, a greater or less proportion of fibrin also may be poured forth. 

 Now when the quantity of Fibrin in the blood is greatly augmented, and the 

 firmness of the walls of the vessels in the inflamed part is diminished by the 

 alterations taking place in their tissue, it is easy to understand that the dispo- 

 sition to the effusion of Fibrin will be much increased. Sometimes the Fibrin 

 is diluted with a large quantity of Serum ; and is poured into a cavity (as that 

 of a serous sac) in the form of a liquid, which afterwards separates into clot 

 and serum. 



608. Should the Inflammation increase in intensity, a complete stagnation 

 of blood in the tissue most affected, or even in an entire organ, will be the 

 result ; and this will occasion its death. If a large part be thus entirely de- 

 stroyed at once, the process is termed Gangrene; and it separates from the 

 living part at a line where the Inflammation is less intense, and where there 

 is a deposit of Fibrin, which serves the important purpose of closing the mouths 

 of the blood-vessels that are laid open by the process. If the destruction of 

 tissue, however, be interstitial, the dead parts are not thus thrown off, but are 

 taken up by the absorbent process ; and thus the cavity of an Jlbscess, or of 

 an Ulcer is formed. This cavity is usually bounded by tissue that has been 

 consolidated by the effusion of Fibrin ; a fact readily accounted for on the 

 principles just stated. For the death and removal of tissue take place where 

 the Inflammation has been most intense, and the stagnation most complete ; 

 which is in the centre of the inflamed spot ; and the fibrinous effusion, the 

 result of moderate inflammation, is poured into the surrounding tissue. The 

 elements of Liquor Sanguinis are poured into the central, as well as the peri- 

 pheral, portion of the inflamed tissue ; but they assume a different form that 

 of Pus. It would appear as if the influence of the surrounding death and 

 decay produces a degradation of their character ; so that they become entirely 

 aplastic or unorganizable, although immediately derived from Blood highly 

 charged with Fibrin. 



609. Between Coagulable Lymph and Purulent effusions, there are many 

 degrees of transition ; the very same deposit being frequently organizable at 

 one part, presenting the character of a tough fibrous membrane, interspersed 

 with corpuscles, whilst it is friable in another, from want of complete fibril- 

 lation in the fluid portion of the effusion, and is entirely destitute of tenacity 

 in a third portion, especially the superficial part, or free surface, of the deposit. 

 When examined by the Microscope, Pus is found to be characterized by the 

 presence of a number of cells of a peculiar aspect, having a very tuberculated 

 or mulberry surface ; these are seen floating in a fluid, termed liquor puris, 

 which is of an albuminous or low fibrinous character, being entirely destitute 

 of organizability. Now the production of Pus in an inflamed part, or in other 

 words, the act of Suppuration, may be due to one of three causes, viz., the 



* Medico-Chirurgical Transactions, vol. xxvi., p. 51. 

 39* 



