186 THE FLUIDS. 



Uses. The use of the normal exudations is explained in the 

 preceding sentence, since they alone afford the materials for the 

 reparative process. Inflammatory exudations are, however, to be 

 regarded as pathological, and are almost always productive of only 

 mischief. 



Varieties of Exudations. 



Exudations differ much in different circumstances, in respect to 

 the properties of their chemical constituents ; but the only varie- 

 ties necessary to be mentioned here are the euplastic, or highly 

 organizable, and the cacoplastic, or imperfectly organizable. In- 

 flammatory exudations are always cacoplastic ; and non-inflamma- 

 tory exudations are so also in unfavorable circumstances, especially 

 when the blood is impoverished. In favorable circumstances, and 

 in which exudations are required as in incised wounds the latter 

 are euplastic. Plastic exudations contain more fat than those not so. 



Mr. Paget's division into thefibrinous and the corpuscular exuda- 

 tions has reference to the forms of organization occurring in them, 

 and which may or may not be due to original differences in their 

 constituents, as will appear under the next head. All pure exuda- 

 tions at first manifest the transparency and other physical properties 

 of the liquor sanguinis, as has been already stated. The physio- 

 logical and histological differences between the inflammatory and 

 non-inflammatory exudations, as shown by their subsequent or- 

 ganization, will next be explained. 



Changes occurring in Exudations. 



Exudations, whether inflammatory or not, generally become co- 

 agulated soon after their separation from the vessels, and then 

 promptly present the fibrillated appearance already described. (Fig. 

 49.) They may subsequently be (1) reabsorbed, or (2) may be or- 

 ganized into a new tissue ; or (3) may be converted into pus. 



1. Absorption of an exudation may occur either before or after 

 coagulation. In almost all cases it is desirable that inflammatory 

 exudations be reabsorbed as soon as possible, since only swelling of 

 the part and other mischiefs result from their presence. The ex- 

 ceptions to this proposition are very few, and will be insisted upon 

 by those only who still maintain the doctrine never sustained by 

 proof of any kind that inflammation and the reparative process 

 are identical. E. g. it is never desirable that the plasma exuded in 



