8 THE WORK OF THE DIGESTIVE GLANDS. 



the observer, but less comfortable for the animal, for the dog quickly 

 tires and becomes restless. Nevertheless, the animal soon learns 

 to sleep excellently, even under these circumstances, especially if one 

 makes its position more comfortable by supporting the head. When 

 first used in the laboratory, however, it is better to collect the juice 

 from the dogs in the lying posture. In such cases it is necessary to 

 employ a suitable vessel pressed more or less firmly to the body-wall 

 beneath the opening of the duct. 



I have intentionally described all these accidents which may arise 

 in connection with the formation of a permanent pancreatic fistula. I 

 wished to show how difficult an apparently easy problem may become 

 when dealing with material of such a peculiar nature. 



Our solution of the problem is evidently by no means an ideal one. 

 It would be in the highest degree desirable to possess a method which 

 would permit us to collect the juice when desired during the experi- 

 ment and yet allow it to return to the intestine during the intervals. 

 In this way not only would much pancreatic juice be saved to the 

 organism, but the possibility of other serious disturbances of the 

 digestive glands from the effects of the fistula would also be excluded. 

 One may justly assume that the continued loss of so important a 

 secretion as the pancreatic juice is compensated, on the one hand, by 

 an augmented or otherwise altered activity of the remaining digestive 

 glands, or, on the other, that this loss is rendered less injurious by a 

 depreciation in the value of that which falls useless to the floor. "VVe 

 must not, however, overrate the importance of these somewhat far- 

 fetched suppositions. Further investigations showed us how clear, 

 consistent, and instructive are the numerous results which we 

 obtained by this method. 



A more recent method which has been published by the Italian inves- 

 tigator Fodera * approximates to a perfectly faultless one. He succeeded 

 in causing a T-shaped metallic cannula to heal into the duct, so that 

 the juice, as one must accept it, could be either collected on the outside, 

 or by closing the outer end of the tube, be diverted into the alimentary 

 canal. This experiment possesses, however, for the time being, an 

 important defect ; we have no guarantee that, notwithstanding the 

 outflow from the tube, there may not be a considerable quantity still 

 entering the intestine. 



The evolution of a method for obtaining gastric juice and observing 

 its secretion was no less difficult and protracted. We may pass over 

 the old and admittedly inadequate experiments, and consider more 

 carefully the starting-point of the method now in use the making of a 



* Moleschott's Unterswc/tivngen :itr Xttturlclirc dcr Mt'iiscJi-eii >u>d der T'icrc. 

 Bil. xvi. 18%. 



