VARIATIONS AND FUNCTIONS OF BILE. 197 



The solid residue was composed as follows : 



Neutral fat, soluble in ether . . 43.710 grains. 



Fat, with traces of biliary matter . 77.035 " 



Alcohol extract with biliary matter 58.900 containing 1.085 grs. of sulphur. 



Substances not of a biliary nature 



extracted by muriatic acid and 



hot alcohol . . . . 148.800 containing 1.302 grs. of sulphur. 



2.387 



Fatty acids with oxide of iron . 98 425 

 Residue consisting of hair, sand, &c., 207.080 



633.950 



Now, as it has already been shown that the dog secretes, during 

 24 hours, 6.916 grains of solid biliary matter for every pound weight 

 of the whole body, the entire quantity of biliary matter secreted 

 in five days by the above animal, weighing 17.7 pounds, must have 

 been 612.5 grains, or nearly as much as the whole weight of the 

 dried feces. But furthermore, the natural proportion of sulphur 

 in dog's bile (derived from the uncrystallizable biliary matter), is six 

 per cent, of the dry residue. The 612.5 grains of dry bile, secreted 

 during five days, contained, therefore, 36.75 grains of sulphur. 

 But the entire quantity of sulphur, existing in any form in the 

 feces, was 5.952 grains; and of this only 2.387 grains were derived 

 from substances which could have been the products of biliary 

 matters the remainder being derived from the hairs which are 

 always contained in abundance in the feces of the dog. That is, 

 not more than one-fifteenth part of the sulphur, originally present 

 in the bile, could be detected in the feces. As this is a simple 

 chemical element, not decomposable by any known means, it must, 

 accordingly, have been reabsorbed from the intestine. 



We have endeavored to complete the evidence thus furnished by 

 Bidder and Schmidt, and to demonstrate directly the reabsorption 

 of the biliary matters, by searching for them in the ingredients of 

 the portal blood. We have examined, for this purpose, the portal 

 blood of dogs, killed at various periods after feeding. The animals 

 were killed by section of the medulla oblongata, a ligature imme- 

 diately placed on the portal vein, while the circulation was still 

 active, and the requisite quantity of blood collected by opening 

 the vein. The blood was sometimes immediately evaporated to 

 dryness by the water bath. Sometimes it was coagulated by boil- 

 ing in a porcelain capsule, over a spirit lamp, with water and an 

 excess of sulphate of soda, and the filtered watery solution after- 

 ward examined. But most frequently the blood, after being col- 



