198 THE BILE. 



lected from the vein, was coagulated by the gradual addition of 

 three times its volume of alcohol at ninety-five per cent., stirring 

 the mixture constantly, so as to make the coagulation gradual and 

 uniform. It was then filtered, the moist mass remaining on the filter 

 subjected to strong pressure in a linen bag, by a porcelain press, 

 and the fluid thus obtained added to that previously filtered. The 

 entire spirituous solution was then evaporated to dryness, the dry 

 residue extracted with absolute alcohol, and the alcoholic solution 

 treated as usual, with ether, &c., to discover the presence of biliary 

 matters. In every instance blood was taken at the same time from 

 the jugular vein, or the abdominal vena cava, and treated in the 

 same way for purposes of comparison. 



We have examined the blood, in this way, one, four, six, nine, 

 eleven and a half, twelve, and twenty hours after feeding. As the 

 result of these examinations, we have found that in the venous 

 blood, both of the portal vein and of the general circulation, there 

 exists a substance soluble in water and absolute alcohol, and pre- 

 cipitable by ether from its alcoholic solution. This substance is 

 often considerably more abundant in the portal blood than in that 

 taken from the general venous system. It adheres closely to the 

 sides of the glass after precipitation, so that it is always difficult, 

 and often impossible, to obtain enough of it, mixed with ether, for 

 microscopic examination. It dissolves, also, like the biliary sub- 

 stances, with great readiness in water ; but in no instance have we 

 ever been able to obtain from it such a satisfactory reaction with 

 Pettenkofer's test, as would indicate the presence of bile. This is 

 not because the reaction is masked, as might be suspected, by some 

 of the other ingredients of the blood ; for if at the same time, two 

 drops of bile be added to half an ounce of blood taken from the 

 abdominal vena cava, and the two specimens treated alike, the ether- 

 precipitate may be considered more abundant in the case of the 

 portal blood ; and yet that from the blood of the vena cava, dis- 

 solved in water, will give Pettenkofer's reaction for bile perfectly, 

 while that of the portal blood will give no such reaction. 



Notwithstanding, then, the irresistible evidence afforded by the 

 experiments of Bidder and Schmidt, that the biliary matters are 

 really taken up by the portal blood, we have failed to recognize 

 them there by Pettenkofer's test. They must accordingly undergo 

 certain alterations in the intestine, previously to their absorption, 

 so that they no longer give the ordinary reaction of the biliary sub- 

 stances. We cannot say, at present, precisely what these alterations 



