THEIR CLASSIFICATION. 131 



science, he will nowhere find a better guide than in Henle's recent 

 and masterly exposition of this subject,* where the accumulated 

 stores of histological materials have been carefully sifted, the 

 objects clearly delineated, and the various points of the inquiry 

 ably treated. 



Since the exudations manifest every variety of difference, partly 

 in reference to their morphological characters, partly in the meta- 

 morphoses which they undergo, and partly from their different 

 modes of origin, and since we are still far from comprehending 

 their differences from a chemical point of view, the only principle 

 to be adopted in making a division of the whole subject is to 

 choose a plan of arrangement based upon direct observation of 

 the characteristic differences which exist in the physical properties 

 of the objects. Great as has been the labour expended in the 

 attempts to describe and classify the exudations in accordance with 

 their external characteristics, we think the chemist can find no 

 safer guide than that most accurate pathologist Rokitansky.f 

 For although the description which Rokitansky gives of the 

 differences of the exudations may be interwoven with designations 

 and the indications of a theory of erases which the chemist does 

 not recognise, we nevertheless meet with the most minute obser- 

 vations which are perfectly true to nature, and which alone ought to 

 form the basis of a more extended physico-chemical investigation. 

 We therefore purpose following Rokitansky's mode of arrange- 

 ment in giving the few known chemical relations ; and shall 

 consider the exudations 1, as fibrinous, which are again subdi- 

 vided into simple plastic and croupous ; 2, as albuminous; and 

 3, as purulent, under which head are included ichorous and 

 heemorrhagic exudations. 



The attacks which have been made by many of our chemical 

 physicians against Rokitansky's mode of considering and classi- 

 fying the exudations, apply less to his own views than to those of 

 some of his pupils and followers, who have distorted his facts by 

 the most wild and paradoxical hypotheses. In reference, how- 

 ever, to any objections which may be advanced against the mode 

 of expression adopted by the founder of pathological anatomy, it 

 should be observed that the expressions albuminous or serous 

 exudations are intended simply to designate a physically and defi- 

 nitively characterised form of exudation ; but that Rokitansky had 



* Handb. d. rationellen Pathologie. Braunschw. Bd. 2, S. 667-832. 

 t Handb. d. allgem. pathol. Anatomie. Bd. 1, S. 194-224, and in other 

 places. 



K 2 



