150 THE WORK OF THE DIGESTIVE GLANDS. 



digestion, which we saw then to be an essential characteristic of the 

 work of these glands, has been even more clearly expressed in our later 

 experiments, especially in connection with the pancreatic secretion. 

 The ferment activity of the pancreatic juice harmonises in the most 

 beautiful manner with the nature of the food to be digested. Thus, 

 with a diet containing a large proportion of fat, the fat-splitting ferment 

 predominates, and so on. (Experiments of Dr. Walther.) Further, we 

 have gained a better knowledge of the mechanism of this adaptation ; 

 we have discovered new factors in the nervous machinery of these 

 glands nerves which restrain their activity. (Experiments of Dr. L. B. 

 Pojnelski.) We have determined the relationship of each individual 

 element of the food to the receptive part of the nervous apparatus of 

 the glands. And in this way we have convinced ourselves by direct ex- 

 periment that the special nature of the gastric juice poured out on bread, 

 with its strong digestive power, is determined by the fact that starch 

 is mixed with the proteid. (Dr. J. 0. Lobassow.) Similarly, we have 

 been able to explain nearly all the quantitative and qualitative changes 

 in the secretions of the digestive glands which occur during the whole 

 period of activity. It is also very gratifying to me to be able to state 

 that both Russian and foreign representatives of clinical medicine 

 have made use of the results of our physiological investigations and 

 with good effect. Further, all our hypotheses and discoveries have 

 gained wide recognition in foreign lands, and this encourages us to 

 extend our work. 



I now come to a new subject in our researches, in which we see that 

 what is true of science generally is likewise true of every individual scien- 

 tific problem. Everything does not mean advance ; we often meet with 

 a standstill, sometimes even take a retrograde movement. A striking 

 example of this is .shown in the investigation of the salivary glands. 



About the middle of the last century, after the appearance of the 

 classical work of Mitscherlich, a number of talented investigators, 

 such as Claude Bernard, Schiff, and others, endeavoured to solve the 

 interesting and natural questions of how much and what kind of 

 saliva is poured into the mouth mider different conditions, such as the 

 act of mastication, the entry of foods of different tastes and different 

 degrees of dryness, ifec. It resulted and the same is to be expected 

 from every organ in the body that the work of the salivary 

 glands is capable of adapting itself to given conditions, that is to 

 say, bears a definite relationship to the requirements which must 

 be fulfilled by the saliva produced. And yet we read in modern 

 text-books of physiology, which purport to sum up the achievements of 

 our science, that every form of stimulus applied to the cavity of the 

 mouth, be it mechanical, chemical, thermal, or otherwise, excites the 



