THE EFFECTS OF FAT. 141 



pleasant. The meaning of this is easy to guess. The repast, begun 

 with pleasure, consequent on the pressing need for food, must also, 

 notwithstanding the stilling of hunger, be terminated with an agreeable 

 sensation. At the same time the digestive canal must not be burdened 

 with work at this stage, it is only the gustatory nerves which should be 

 agreeably excited. After thus dealing in general with the usual 

 arrangement of our meals, we may now speak of some special points. 



Above all comes the acid reaction of the food. It is apparent that 

 acidity enjoys a special preference in the human taste. We use quite a 

 number of acid substances. Thus, for example, one of the commonest 

 seasoning substances is vinegar, which figures in a number of sauces 

 and such like. Further, many kinds of wine have a somewhat acid 

 taste. In Russia, ktvas, especially in the acid form, is consumed in 

 great quantities. Moreover, acid fruits and green vegetables are used 

 as food, and they are either of themselves acid, or made so in the pre- 

 paration. In medicine this instinct is likewise often made use of, and 

 acid solutions, especially of hydrochloric and phosphoric acids, are pre- 

 scribed in digestive disturbances. Finally, nature itself constantly 

 endeavours to prepare lactic acid in the stomach in addition to the 

 hydrochloric acid. The former arises from the food introduced, and is 

 consequently always present. These facts are all physiologically com- 

 prehensible when we know that an acid reaction is not only necessary 

 for an efficient action of the peptic ferment, but is at the same time 

 the strongest excitant of the pancreatic gland. It is even conceivable 

 that in certain cases the whole digestion may depend upon the stimula- 

 ting properties of acids, since the pancreatic juice exerts a ferment 

 action upon all the constituents of the food. In this way, acids 

 may either assist digestion in the stomach where too little gastric 

 juice is present, or bring about vicarious digestion by the pancreas 

 where it is wholly absent. It is easy, therefore, to understand why the 

 Russian peasant enjoys his kwas with bread. The enormous quantity 

 of starch which he consumes, either as bread or porridge, demands a 

 greater activity upon the part of the pancreatic gland, and this is 

 directly brought about by the acid. Further, in certain affections of 

 the stomach, associated with loss of appetite, we make use of acids, both 

 from instinct as well as medical direction, the explanation being that 

 they excite an increased activity of the pancreatic gland, and thus 

 supplement the weak action of the stomach. It appears to me that a 

 knowledge of the special relations of acids to the pancreas ought to be 

 very useful in medicine, since it brings the gland a digestive organ at 

 once so powerful and so difficult of access under the control of the 

 physician. We could, for instance, intentionally discard digestion in 

 the stomach, and thus transfer it to the bowel by prescribing substances 



