242 THE BILE. 



the addition of a drop or two of a solution of cane sugar to 

 the liquid suspected to contain bile. Sulphuric acid is then 

 added to the extent of about one-third of the portion of the 

 liquid which is being tested. A violet and red tint is then 

 gradually produced if bile be present. 



The function of the bile in digestion is, as we have already 

 said, still involved in the greatest obscurity. Some have 

 considered that it is simply excrementitious. and have sup- 

 ported their opinion by the fact of animals with biliary fistula 

 living for an almost indefinite period, although no bile reaches 

 the intestine, provided the quantity o f food supplied be suf- 

 ficient. 



The quantity of bile bears a certain proportion to the 

 weight of the body in all animals, and is very much affected 

 by the quantity of food taken. 



Colin has drawn the following conclusions from his experi- 

 ments in the horse, \stly, That the biliary secretion is con- 

 tinuous, whether the animals are operated upon during the 

 process of digestion, or have been fasting. Zndly, That this 

 secretion is not subject to the variable activity which is 

 observed with regard to the salivary and pancreatic fluids. 

 Srdly, That tin's function is slowest when digestion is most 

 disturbed, and animals grow weaker after the operation. 

 ^thly, For three or four hours after a fistula has been made 

 in the horse, the secretion amounts to 250 or 300 grammes, 

 so that in twenty-four hours a horse would secrete about 

 6000 grammes, or twelve pounds weight, othly, The bile 

 appears always to possess the same characters, the same 

 degree of consistence, of fluidity, the same colour and 

 reaction. 



For every pound weight of the entire body, there is secreted 

 in the dog 140 grains of bile, in the sheep 178. These 

 respectively containing 5712 grains, and 9'408 grains of 



