360 Drs. S. Martin and D. Williams. [Feb. 21, 



mixture 2 per cent. To b 0'6 per cent, dried pig's bile, and to c and d 

 2 per cent, dried pig's bile were added and dissolved ; to a, 6, and c 

 equal quantities of glycerine extract of pig's pancreas were added and 

 all the vessels were placed in a water-bath at 34 C. The colour 

 reaction with iodine given by d was unchanged throughout, but a, 

 fc, and c gave a varying colour reaction, and changing most rapidly 

 with c and least rapidly with a. After remaining in the water- 

 bath for eight minutes the vessels were taken out and their contents 

 boiled, to destroy the ferment, and the amount of dextrose estimated 

 by Fehling's method ; a contained 0*45 per cent., I 0*59 per cent., and 

 c 0'74 per cent. 



A large number of experiments were performed of which the above 

 are quoted as examples, and the conclusion to which we were led 

 was that digestion of starch by extract of pig's pancreas was 

 hastened in the presence of pig's bile. We next sought to ascertain 

 (1) whether this was a property of the bile solids as a whole, or of 

 one or other constituent ; and (2) the nature of this hastening action, 

 whether, that is to say, the bile only hastened the transformation of 

 starch into dextrin, or whether there were also constant increase in 

 the amount of sugar formed. 



Firstly, as to whether the effect is to be ascribed to the action of 

 any one constituent of the bile. Pig's bile contains bile salts (chiefly 

 hyoglycocholate of sodium*), bile pigment, cholesterin, soaps, and 

 salts together with mucin. We found that an extract of dried bile 

 made with absolute alcohol retained the power of hastening pancreatic 

 digestion of starch, and finally that it was also possessed by the bile 

 salts. It was found in this case also that the amount of sugar esti- 

 mated as dextrose was greater as the proportion of bile salts added 

 to the mixture was increased up to 2 per cent., beyond which our 

 experiments have not gone. Thus in one experiment the amount of 

 sugar found after half an hour's digestion (a) in a mixture to which 

 0'6 per cent, of bile salts had been added = T03 per cent. ; (I) in a 

 mixture to which 2'0 per cent, of bile salts had been added = 1'25 

 per cent. ; and (c) in a mixture to which no bile salts had been added 

 TO per cent. ; a large amount of starch mixture was used in this ex- 

 periment and 0'8 per cent, pancreatin added. 



Secondly, as to the nature of the process, whether the bile hastened 

 the transformation of starch into dextrin, or whether there was also 

 an increase in the amount of sugar ; this was found to be a somewhat 

 difficult question to solve. The quantitative estimation of a mixture 

 of starch, dextrin, and sugar, or of dextrin and sugar was found to 

 present many difficulties. The amount of sugar was readily estimated 



* Jolin (' Zeits. f. Physiol. Chemie,' yol. 11, p. 417) describes a- and j8-hyoglyco 

 cholate. 



