166 THE WORK OF THE DIGESTIVE GLANDS. 



movements of the stomach are arrested, clearly with the object of 

 allowing the food to remain in the cavity and be worked up in a suitable 

 manner. Thus milk lapped up by the dog, in contrast to that intro- 

 duced unobserved through the fistula, does not pass at once into the 

 duodenum, although evacuating movements may have been going on 

 immediately before. The spontaneous movements also cease when acid 

 fluids are poured into the stomach through the fistula, and this is a 

 *urther confirmation of the relationship already mentioned. You see, 

 gentlemen, that, in the study of stomach movements, and indeed at 

 the very threshold of the subject, we have encountered the same 

 characteristics which we saw in our earlier investigation? namely, the 

 purposive nature of the phenomena and the intervention of psychical 

 influences. I have one further remark to acid, namely, that experi- 

 ments of Dr. S Lintwarew have shown that fat also, when poured into 

 the duodenum, regulates the emptying of the stomach in even a more 

 striking manner. 



In the foregoing I have given you a short summary of our later 

 physiological experiments. I see quite well how much yet remains to 

 be done. "VVe are far from having the matter fully under control, but 

 the next advances are clearly indicated, and we are justified in hoping 

 that in the future our field of work will be even more accessible to 

 investigation than in the past. 



The animals employed in these researches, and which for the most 

 part served for observation during many months or years, occasionally 

 became ill, and sometimes the affected organ was that actually under 

 investigation. At first such accidents annoyed us considerably, but it 

 soon became evident that our discontent arose from an obvious miscon- 

 ception of the nature of the facts. 



Why should a pathological condition of the digestive apparatus not 

 appeal to us ? What is a pathological condition ? Is it not the effect 

 produced upon the organism by the encountering of an unusual condition, 

 or, more correctly said, an unusually intensified ordinary condition ? 

 Suppose one received a mechanical shock or became exposed to the effects 

 of great cold or heat, or to the attack of pathogenic micro-organisms to a 

 degree beyond the usual extent of these influences, a general struggle 

 begins on the part of the organism against these agencies. The apparatus 

 of defence is immediately called into play. This consists of parts of the 

 body which, like the others, live within it, and share in the maintenance 

 of the general equilibrium of the whole living organism. Consequently 

 they are worthy objects for physiological investigation. But physiology 

 learns of them only through illness ; at other times their work is not to 

 be seen. The struggle in question leads either to a repulse of the 



