72 BILE. 



we must be careful not to confound with the globules of separated 

 biliary acids, which are often observable. Gorup has found fat- 

 globules in the bile of persons who had died from typhus and from 

 tuberculosis (in the colliquative stage). We have already alluded 

 to the fact (see vol. i. p. 253), that in such cases free fat also 

 passes into the urine. 



It is very seldom that the bile has been found to have an acid 

 reaction, and in none of these cases has it been carefully analysed. 



Solon, Scharlau, and Gorup-Besaiiez occasionally found the 

 bile acid in typhus ; this may, however, depend partly on the 

 spontaneous decomposition of the bile, and the consequent libera- 

 tion of its resinous acids, and partly on the fact that pus is effused 

 into the gall-bladder ; for, as we shall subsequently show, this fluid, 

 when contained in an enclosed space,' often becomes acid with 

 great rapidity. 



According to Solon, the bile is sometimes as acrid as chlorine, 

 and bleaches litmus. I believe that I have observed two cases of the 

 kind whicli probably led Solon to adopt this view ; this bile certainly 

 decolorized litmus paper, so that it remained neither blue nor red, 

 but its colouring matter was so dissolved out, or covered by the 

 yellow pigment of the bile, that the original tint seemed wholly to 

 have disappeared; in a less degree this is the case with every 

 specimen of bile. 



The following may be regarded as the simplest method of 

 analysing the bile. We treat the fluid with half its volume, or 

 from that to its own volume, of spirit (83-g-). This generally only 

 throws down mucus, which carries with it any epithelium that may 

 be present ; we rince the precipitate first with spirit, and then with 

 water, and dry and weigh it. The bile thus freed from mucus, is 

 deprived of its water, by being placed first on the water-bath, and, 

 subsequently, under the air-pump on a sand-bath heated to 100 ; 

 the high temperature in this process of desiccation is less neces- 

 sary for the purpose of effecting the drying quickly than for con- 

 verting the residue of the bile by the rapid evaporation of the 

 water into a porous spongy, puffy substance, which admits of 

 being extracted by the ordinary menstrua with comparative facility. 

 As the residue of scarcely any other animal fluid attracts moisture 

 so readily from the air, especial care must be paid to the weighing 

 of its solid constituents ; after the mass has cooled in vacua, air 

 from which the aqueous vapour has been extracted by chloride of 

 calcium must be drawn into the receiver, and the weighing must 

 be completed as quickly as possible. The residue must then be 



