ANALYSIS OF CURVE OF GASTRIC SECRETION. 83 



pieces of flesh were introduced through the fistula. The morsels were 

 threaded on a string, the free end of which was fastened to the fistular 

 cannula by inserting a cork. The dog was then brought into a separate 

 room and left to itself. A like number of pieces was introduced into the 

 stomach of the other dog in the same way, but during the process, a 

 vigorous sham feeding was kept up, the animal being afterwards left alone. 

 Each dog received 100 grms. of flesh. Since then an hour and a half have 

 elapsed, and now we may draw the pieces of flesh out by mean!- of the 

 thread and weigh them. The loss of weight, and consequently the amount 

 of flesh digested, is very different in the two cases. In that of the dog 

 without sham feeding, the loss of weight amounts to merely G grms., 

 while the flesh withdrawn from the stomach of the other dog weighs 

 only 70 grms., that is to say, was reduced by 30 grms. Thi*, 

 therefore, represents the digestive value of the passage of food through 

 the mouth, the value of an eager desire for food ; the value of an 

 appetite. 



I give also a series of figures obtained by Dr. Lobassoff in analogous 

 experiments. Into the dog's stomach 25 pieces of flesh (100 grms.) were 

 brought. The flesh remained two hours in the cavity. Without sham 

 feeding, G'5 per cent.; with eight minutes' sham feeding, 31'6 per cent, 

 of the quantity was digested. 



Again : the flesh remained an hour and a half in the stomach; with- 

 out sham feeding 5'G per cent., with five minutes' sham feeding 15 per 

 cent, was digested. 



Once more : the flesh remained five hours in the stomach ; without 

 sham feeding 58 per cent., with sham feeding 85 per cent, was digested, 

 the balance of undigested food being 42 per cent, in the one case and 

 15 per cent, in the other. 



I must, however add, that from the nature of this experiment, it is 

 not well adapted for class demonstration, and may often fail. On 

 the one hand, it is not at all easy to conceal the introduction of the 

 flesh from the dog ; on the other, the unusual and distracting surround- 

 ings of the animal often cause a short period of sham feeding to have 

 less effect than would otherwise pertain. In order to avoid such 

 failures, it is better before an audience, to carry out this experiment 

 only on dogs accustomed to appear in the lecture theatre, and of whose 

 temperament the experimenter is well assured. 



I hope you have now been convinced of the great importance 

 which is to be attached to the passage of food through the mouth and 

 oasophagus, or, in other words and this, according to our former 

 experiences, means the same thing to the eager desire for focd. 

 Without this longing, without the assistance of appetite, many forms of 

 food-stuff which gain entry to the stomach remain wholly devoid of 



