PUS. 157 



tissue, or a product of fibrin entering into a state of suppuration ; 

 but these conjectures have not hitherto been confirmed by the 

 positions in which this substance occurs, so far as they have yet 

 been accurately observed, or by its chemical reactions. 



Scherer has submitted to elementary analysis several specimens 

 of pyin obtained from different exudations, and has found that 

 their composition was almost precisely the same as that of protein; 

 however, he also found other constituents of the exudations which 

 appeared very similar to pyin, but differed very much from it in 

 composition, being especially remarkable for their abundance of 

 nitrogen (== 22'3/f). 



Casein does not occur in normal pus, and its presence has not 

 been proved with certainty even in abnormal forms of the secre- 

 tion. The deficiency of our knowledge of the protein-bodies and 

 their immediate derivatives is nowhere more forcibly shown than 

 in the investigation of pathological products. 



The quantity of fat in pus, the occurrence of which has been 

 regarded as highly characteristic, differs extremely according to 

 the source from whence it is derived; although, when compared 

 with the amount contained in many other fluids, it is rather large. 

 It is very considerable, and is always present in all abscesses of the 

 mammae ; cancer of the breast, however, always exhibits a larger 

 amount of fat than any other carcinomatous growth. In ordinary 

 pus the quantity of fat varies, according to our observations, which 

 agree with those of Giiterbock, Valentin,* and von Bibra,t from 

 2 to 6-g-. The different fats seem to consist of olein and margarin, 

 alkaline oleates and margarates, and variable quantities of choles- 

 terin. We cannot entirely admit the correctness of Simon's 

 view, who held that the fat-globules which appear on the addition 

 of acetic acid to pus, consist principally of liberated fat derived 

 from the corpuscles, since it may also be dependent on the decom- 

 position of the soaps dissolved in the pus-serum ; and, indeed, fat- 

 globules are often perceived in pus- serum after it has been treated 

 for some time with acetic acid, which were previously not to be 

 perceived. Pus occasionally contains a tolerably large amount of 

 cholesterin, and Valentin found as much as 1^- of this substance in 

 pus which had been taken from an abscess in the thigh. On a 

 careful examination of the masses of fat extracted with hot alcohol 

 and ether from the residue of the pus, a little fat containing phos- 



* Valentin's Repert. 1838, S. 307. 



t Chem. Untersuch. verschiedener Eiterarten u. s. w. Berlin, 1842. 



