208 BLOOD. 



that organ, and the neutral compound is thus formed. The serum of 

 the portal blood appears, moreover, less turbid on the addition of 

 water than that of the splenic vein ; while that of the hepatic veins 

 exhibits great turbidity on the addition of water ; and here the 

 albumen of the portal vein, probably, loses a portion of the alkali 

 which is applied to the formation of the bile. 



In accordance with Scherer's view, we must regard the different 

 form in which the albumen coagulates, as dependent upon the 

 different quantity of alkali which it contains (see vol. i. p. 333) ; 

 but still we often observe, that where the alkaline fluid has been 

 neutralised or faintly acidified, in order to induce such a complete 

 deposition of the albumen as may be necessary for its perfect nitra- 

 tion, the albumen of one blood collects less easily in flakes, and is 

 less readily filtered, than that of another. Thus, I constantly found 

 that the albumen of the blood of the hepatic veins only accumulated 

 in masses very slowly, often not till it had been boiled for hours, 

 whilst that of the portal and other veins, as well as that of the 

 arteries, very readily coagulated on boiling after the addition of an 

 acid, and that it rapidly sank, leaving a clear supernatant fluid. 



Since, as we have already observed, ordinary chemical inves- 

 tigations, and more especially elementary analyses, still fail to 

 throw much light on the enquiry into the essential differences in 

 the protein-bodies, C. Schmidt* has conceived the happy idea 

 of bringing substances that are readily capable of fermentation or 

 decomposition into contact with the constituents of the blood 

 under favouring conditions, and thus employing sugar, urea, amyg- 

 dalin, asparagin, &c., as tests for the presence of certain modifi- 

 cations of albumen; as yet, however, the only results at which he 

 has arrived, are that the blood-cells of a healthy individual (but 

 not the intercellular fluid) contain one substance which yields 

 sugar-ferment as the product of its spontaneous decomposition, 

 and another which similarly yields urea-ferment. In diseases, as 

 for instance in cholera, one or the other of these fermenting bodies 

 is increased to a great degree. 



We have already (in vol. i., pp. 249 and 279) fully considered the 

 fats of the serum, and we need, therefore, here simply remark that 

 only a small quantity of free fat occurs in the serum, while saponified 

 fat is always present in large quantities, as well as the crystallisable 

 lipoids, cholesterin, and serolin. It cannot be shown, with cer- 

 tainty, that the serum contains any phosphorised fats. We shall 

 perceive from special numerical results, that the quantity of the fat, 

 * Characteristik der Cholera, S. 5768. 



