WORK OF THE DIGESTIVE GLANDS. 



than to build up new theories and search out old facts concerning gland 

 work which have hitherto been rigidly kept in the shade. We may take 

 it that it is mainly because people were so seized with the belief in the 

 direct and simple mechanical explanation, that Bidder and Schmidt's 

 experiment, of the excitation of gastric secretion by mental effect, has 

 been so little taken into consideration, notwithstanding that it appeared 

 so thoroughly reliable and convincing. 



I will now repeat the experiment of mechanical stimulation of the 

 gastric mucous membrane before you in the well-known, traditional, 

 and classic manner. Here is a dog with a gastric fistula on which a 

 cervical resophagotomy has in addition been performed. I open the 

 fistula : as you see, nothing flows out of the stomach ; it was washed 

 out clean with water an hour ago. We take the celebrated feather and 

 also a tolerably strong glass rod. Folds of blotting-paper saturated 

 with red and blue tincture of litmus are placed at hand. I now ask 

 my assistant to continuously move the feather and glass rod, alternately, 

 in all possible directions in the stomach, changing from one to the other 

 every five minutes. On removal from the stomach each is carefully 

 dried with red and blue blotting paper. You have all seen, gentlemen, 

 that this procedure has now been kept up for half an hour. From the 

 fistular orifice not even a single drop has escaped, and, moreover, the 

 drops of moisture, on all the pieces of red blotting-paper I have 

 been able to hand to you, have assumed a distinct blue tinge, caused by 

 the moisture of the alkaline mucous membrane. The blue pieces, however, 

 have merely been made wet without altering their colour. Consequently, 

 with the most thorough mechanical stimulation of the whole cavity of 

 the stomach, we have not been able to find a single spot possessing a 

 noticeable acid reaction. Where, then, are the streams of pure gastric 

 juice of which we read in text- books ! What objection can be raised 

 against the conclusiveness of this experiment ? In my opinion only one: 

 that we are dealing with a dog out of health, whose gastric glands from 

 some possible cause, are unable to react normally. This single objection 

 can be set aside before your eyes. After failing with the mechanical 

 stimulation, we proceed forthwith to the sham feeding of the same animal. 

 The dog takes the food offered it with keen appetite, and you see that, 

 exactly five minutes after beginning the feeding, the first drops of juice 

 appear from the stomach, followed by others faster and faster. I catch 

 a couple of drops on the blue litmus paper, and you see that they pro- 

 duce bright red specks on the blue sheet. After thirty minutes' sham 

 feeding we have collected 150 c.c. of juice, which, without filtering, 

 looks as clear and transparent as water. 



We cannot, therefore, possibly doubt that, when the proper stimulus 

 is used, the gastric glands react to it in a perfectly normal fashion, 



