196 INFLUENCE OF BILE AND BILE SALTS 



difficult. It is true theoretically that the addition of the fresh 

 bile of an animal to the natural pancreatic juice of the same 

 animal may constitute an ideal method for studying the in- 

 fluence of the former upon the activity of the latter ; but when 

 the exigencies of the case require that the digestive mixture 

 be made by taking 5 drops of the natural pancreatic juice, 

 adding 60 drops of water and 50 drops of a 4 per cent solution 

 of bile,* we see very little reason for believing that the envir- 

 onment is thereby made to approximate any more closely to 

 normal conditions than with the use of artificial extracts of the 

 gland. The point involved is to our minds an important one, 

 aside from the bearing it has upon the question before us. 

 For if it is true that the action of a given agent upon a specific 

 enzyme, or upon the specific power of the enzyme, is neces- 

 sarily different, when added to the natural secretion in which 

 the enzyme is contained from that which results when the same 

 agent is added to an extract of the enzyme, then much of our 

 knowledge regarding the conditions modifying and regulating 

 the action of the digestive enzymes is of questionable value. 



Rachford and Southgate seemingly incline to the view that 

 the conditions under which their experiments were carried out 

 approach closely those normally existent in the duodenum. 

 Granting that this may be so, one is still inclined, after careful 

 scrutiny of the conditions prevailing in their experiments, to 

 wonder what the actual conditions really were. Nowhere is 

 there any mention made of the reaction of the fluids employed, 

 nor of the reaction of the resultant mixture when bile, hydro- 

 chloric acid, and pancreatic juice were combined. To state 

 merely that a given digestive mixture was prepared by adding 

 8 drops of pure pancreatic juice, 30 drops of 0.1 per cent 

 hydrochloric acid, and 50 drops of a 4 per cent solution of bile, , 

 leaves one in great doubt as to whether the mixture so manu- 

 factured was acid, alkaline, or neutral, and if acid whether it 

 contained free or only combined acid. These are obviously 

 very important elements to know if definite conclusions are to 

 be drawn in explanation of the results. Data of this sort, 



* Rachford and Southgate, loc. cit 



