ITS CONSTITUENTS. 67 



tains taurocholic and glycocholic acids in nearly equal proportions. 

 As the bile of the pig contains only from 0'3 to 0'4^ of sulphur, 

 we may hence draw our conclusions regarding the small quantity 

 of hyocholeic or tauro-hyocholic acid contained in it. 



No correct determinations have been made regarding the amount 

 of the pigment, the cholesterin, or the fats and fatty acids in the 

 bile. 



Moreover, the quantitative determinations of the mineral con 

 stituents of the bile, cannot be regarded as altogether trustworthy; 

 the only established fact seems to be that there is a quantity of 

 soda or potash present which is equivalent to the resinous acids ; 

 but the pigment and the fatty acids are also combined with alkalies ; 

 ordinary analyses of the ash, and even those made in accordance 

 with Rosens directions, do not by any means lead to the result that 

 all the alkali combined with organic matter has been accurately 

 determined. The ash of ox-bile is almost the only one which has 

 been carefully examined ; it contains, according to Weidenbusch,* 

 27'70-g- of chloride of sodium, and about 16-g- of tribasic phosphate 

 of soda, with only 3'025-g- of basic phosphate of lime, 1'52 of 

 basic phosphate of magnesia, 0'23-g- of peroxide of iron, and Q'36% 

 of silica. 



I have convinced myself that the bile at all events, that ox- 

 bile contains pre-formed alkaline carbonates, by the same ex- 

 perimental proof which 1 adopted to demonstrate the presence of 

 these salts in fresh blood. If we place bile under the receiver of 

 an air-pump, and abstract the air till the fluid appears to boil, and 

 if we then add acetic acid to the bile thus freed from gas, and 

 again form a vacuum around it, very large quantities of carbonic 

 acid will be evolved, even with the first strokes of the pump. 



I must here remark that, in performing this experiment, 

 perfectly fresh bile, from which the mucus had been removed by 

 alcohol, was employed ; and this, on the addition of acetic acid, 

 yielded no precipitate of fine granules which might *have facili- 

 tated the formation of vesicles of aqueous vapour. The experi- 

 ment may also be easily performed by simultaneously placing 

 acidified and non-acid bile in vacuo, when the difference more 

 readily strikes the eye. In 100 parts of fresh ox-bile, I found, in 

 two quantitative determinations, 0'0846, and 0'1124 parts of the 

 simple carbonate of soda. 



We must here further remark, in connexion with the uncer- 

 tainty of ash-analyses, that the soda combined in the bile with 

 * Fogg. Ann. Bd. 76, S. 386. 



F 2 



