160 EXUDATIONS. 



mass of threads of margarin. After pus has continued standing 

 for several months, the different fats appear in the most beautiful 

 forms, such as no artificial means are able to produce. Even 

 with the naked eye we may detect white granules here and there 

 in the pus ; these granules consist partly of a confused mass of 

 fine threads of margarin, but chiefly of ensiform, lily-leaf-shaped, 

 variously contorted and intersecting bundles of crystals of margaric 

 acid, in which are embedded separate groups of tablets of 

 cholesterin. (F. P. 11, F. 5). 



The distinctions between pus and mucus, which so largely 

 attracted the attention of the physicians of an earlier day, have lost 

 all their supposed importance, since modern physiology has shown 

 that the two fluids are separated only by the most gradual transi- 

 tions, and that the mucus in inflammatory affections of the mucous 

 membrane gradually presents large numbers of cyto'id corpuscles, 

 together with albumen, and thus acquires great similarity, if not 

 a perfect identity with pus, both in respect to its physical and 

 chemical characters. Even the quantity of fat in the purulent fluid 

 secreted by the mucous membrane in a state of inflammation, is 

 very often fully equal to that of genuine pus, a fact to which 

 Guterbock attached great diagnostic value. The pus of the 

 mucous membranes commonly retains the property possessed by 

 mucus of gelatinising on the addition of water or acetic acid. 



Rokitansky's ichorous exudations constitute an ill-defined 

 group, corresponding in many particulars with albuminous exuda- 

 tions. Their chemical properties differ as much as their physical 

 characters ; many are also entirely inaccessible to chemical investi- 

 gation, which would, moreover, be wholly useless, as they fre- 

 quently are nothing more than simple products of putrefaction, 

 and the detritus of the dead (gangrenous) tissue. 



In like manner we cannot ascribe the acid reaction, which is 

 more frequently observed in these than in other exudations, to an 

 organico-vital process ; nor do the scanty chemical investigations 

 which we possess afford the slightest insight into the true source 

 of the irritating character of many of these exudations, more 

 especially of those which were originally coagulable, and deposited 

 clots of fibrin. 



Rokitansky's hamorrhagic exudations are even less amenable 

 to chemical inquiry, and do not, therefore, fall within the scope of 

 the present work, since they can only be considered from a purely 

 anatomical point. 



The hsemorrhagic exudations lead us to the consideration 



