DIGESTION IN THE SMALL INTESTINE. 417 



Colin collected a considerable amount of fluid by placing a clamp on 

 the small intestine of the horse and emptying a considerable portion 

 below it by gentle pressure, and then clamping it several feet below the 

 upper clamp. In this way he obtained from eighty to one hundred and 

 twenty grammes of fluid in half an hour from two meters of the small 

 intestine of the horse. He states, however, that this fluid may be greatly 

 increased by the injection into the loop of a solution of aloes, manna, or 

 soda; and since its composition coincides almost exactly with that of 

 blood-serum, it is probably an exudation. No reliable experiments seem 

 to have been made as to the digestive properties of the fluid obtained in 

 this way. 



Moreau has also succeeded in obtaining a large quantity of liquid 

 by clasping the intestine, as in Colin's method, and then dividing the 

 nerves going to the isolated portion of the intestine. In this operation, 

 also, it is probable that the fluid is an exudation, as it coincides almost 

 entirely with blood-serum in composition ; and here also no experiments 

 as to its digestive powers have been made. 



The author has employed a method for collecting the secretion of 

 the small intestine which is free from most of the objections which 

 may be urged against the methods already described. A fistula is made 

 into the duodenum in the same way as in making a gastric fistula, and a 

 small tube inserted. The operation is readily performed, but in a large 

 number of animals so treated the tube will tear out of the intestine, and 

 the experiment will consequently fail. When the wound has healed the 

 dog should be allowed to fast for at least twenty-four hours, and then 

 the intestine washed out by an injection of lukewarm water through the 

 cannula. A rubber bulb is then to be inserted through the tube into 

 the small intestine and pushed back toward the stomach, taking care, 

 however, that it lies below the opening of the pancreatic and bile ducts ; 

 it then may be distended by water so as to occlude the intestine, and a 

 small bulb with a long tube is then pushed down the intestine and dis- 

 tended with water so as to occlude it below. 



In this way a variable portion of small intestine is shut off' from the 

 contents of the alimentary canal above and below, and its secretion in a 

 state of comparative purity, and in considerable amount, may be then 

 collected. 



Obtained in this way, the intestinal juice has an alkaline reaction ; 

 its specific gravity, 1010; it gives no coagulum on boiling, and yields 

 Millon's reaction, and deposits a heavy precipitate when thrown into 

 absolute alcohol. Its composition in one hundred parts is as follows: 

 Water, 98.86 ; organic matter, 0.54 ; inorganic matter, 0.59. The inor- 

 ganic matter is represented by chlorides and sulphates and carbonates 

 of sodium and potassium. With chlorine-water no red is given, and in 



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