SUPPURATION; ULCERATION; GANGRENE. 353 



phenomena, the simplest result is the effusion of fibrinous matter, or 

 organizable lymph, into the substance of the part inflamed, or upon the 

 nearest free surface ; and thus is produced a condensation of the tissue, 

 or a new growth upon the membrane. But when the depression of 

 vitality is more complete, the tissue at that spot gradually dies and dis- 

 integrates ; and whilst itself undergoing such changes, it gives origin to 

 similar changes in the effused fibrine, which it. converts from a plastic 

 or organizable deposit, into an aplastic or unorganizable one, namely, 

 pus, the cells of which degenerate without passing into any higher or 

 more permanent form of tissue, whilst the liquid through which they 

 are dispersed has lost its coagulating power. Thus is produced the 

 /Suppurating process ; which may either take place in a cavity thus ex- 

 cavated in the .substance of a tissue or organ ; or on a free surface. In 

 either case, the surrounding tissues, which are less inflamed, and in 

 which the vitality is impaired but not destroyed, become consolidated 

 by a deposition of organizable fibrine, which prevents the infiltration of 

 pus through their substance. If this should not occur, through a want 

 of power to generate well-elaborated fibrine, the suppurating process 

 extends itself rapidly, with the most calamitous results ; the properties 

 of pus being such, as to produce a tendency to decomposition, both in 

 the blood, and in the solid tissues into the substance of which it may be 

 carried. 



633. Another consequence of Inflammation is Ulceration, which is 

 a breach of surface caused by the same process as that which forms 

 the cavity of an abscess, namely, the degeneration of the inflamed 

 tissue, and the removal of its particles, either by absorption, or by 

 solution and ejection in pus. Many ulcers commence as abscesses near 

 the surface, which at last come to open upon it ; and others are pre- 

 ceded by inflammation of the superficial tissues, which die and are 

 thrown off, leaving a vacuity, which may be subsequently increased by 

 the extension of the degeneration to the deeper parts. These may 

 either die and be thrown off en masse, constituting what is known as 

 the "sloughing ulcer," or they may disintegrate more slowly, and may 

 be dissolved in the discharge from the ulcerated surface. This dis- 

 charge, when proceeding from a spreading ulcer, is usually of a thin 

 ichorous quality, and has the power of exciting unhealthy action even 

 in healthy parts to which it may be applied ; and it is its change to 

 what has been designated as "laudable pus," that indicates the cessa- 

 tion of the destructive, and the commencement of the reparative pro- 

 cess ( 636). 



634. The state of Gangrene, which consists in the entire loss of 

 vitality of the part, with a complete cessation of the circulation through 

 it, is commonly regarded as a result of Inflammation, when this process 

 occurs in its most intense form ; but it may be more rightly considered 

 as the ultimate consequence of the causes which produce Inflammation. 

 For it is an essential part, as we have seen, of the condition of Inflam- 

 mation, that the vitality of the affected tissues should be lowered ; and 

 thus there is in them always a tendency to death, which is most com- 

 pletely developed in Gangrene. We have a well-marked example of 

 this complete destruction of the life of a part, by the intense operation 



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