INFLAMMATIONS. 11 



various, according to the nature of what is effused, and which 

 may be, 



1. A matter thinner than serum. 



2. An entire and pure serum. 



3. A quantity of red globules. 



4. A matter furnished by particular glands seated in the 

 part. 



5. A mixture of matters from different sources, changed by 

 peculiar fermentation. 



It is the second only which affords a proper pus ; the effusion 

 whereof, whether in suppurating parts or ulcers, seems to be 

 the peculiar effect of an inflammatory state of the vessels ; and 

 for this reason it is, that, when ulcers do not produce a proper 

 pus, a circumstance always absolutely necessary to their heal- 

 ing, we, in many cases, bring the ulcers to a state of proper sup- 

 puration, by the application of stimulants exciting inflammation, 

 such as balsams, mercury, copper, &c. 



" With regard to pus appearing especially in wounds, there 

 is one question which is at least of some curiosity. Why is it 

 that the generation of pus is seemingly of some necessity ? for 

 very often it attends the generation of new flesh in wounds. I 

 own that this is a problem of considerable difficulty, and necessari- 

 ly involved in the whole mystery of nutrition ; and therefore a so- 

 lution of it cannot well be expected. I can see some founda- 

 tion for an approach to this solution, in so far as the extension 

 of the parts is necessary to their growth, and to the accretion 

 of new matter ; the inflammation supervening in wounds may 

 be necessary to the extension ; and the suppuration may serve 

 the purpose of covering and defending the new accretion. 1 ' 



CCLV. When the matter effused into the cellular texture 

 of an inflamed part is tainted with a putrid ferment, this pro- 

 duces, in the effused matter, a state approaching more or less 

 to that of putrefaction. When this is in a moderate degree, 

 and affects only the fluids effused with the substance of the 

 cellular texture, the part is said to be affected with GANGRENE ; 

 but if the putrefaction affect also the vessels and muscles of the 

 part, the disease is said to be a SPHACELUS. 



CCLVI. A gangrene, and its consequences, may arise from 

 a putrid ferment diffused in the mass of blood, and poured out 



