468 REHFUSS— THE NORMAL GASTRIC SECRETION. 



ments are that the perfectly pure secretion varies between 0.3-0.4 

 per cent, of HCL instead of the 0.2 per cent, of chnicians. 



An extensive study was made of the psychic secretion and for 

 this purpose healthy students were selected, the stomach evacuted 

 and residuum removed before any food was taken, and the tube 

 left /';; situ. They were then placed in front of a weighed steak, and 

 the secretion from the sight and odor of food recorded by complete 

 interval evacuations, this was followed by the chewing of the meat 

 but no material could be swallowed, all meat being expectorated 

 after a definite time interval of chewing. These experiments, the 

 first ever performed on healthy non-traumatized hunian subjects, 

 and as yet unpublished, are full of interesting data. In 33 separate 

 observations on about 12 subjects, the following points were 

 recorded : 



(a) There is a definite psychic secretion varying in duration of 

 from 60-80 minutes, perhaps longer if the psychic stimulus is 

 continued. 



(b) There is no latent period as Pavlov indicated. 



(c) The amount of secretion in the series without atropine 

 varied in 14 pure psychic cases from 105 c.c. to 274 c.c. with an 

 average of 122 c.c. during the period. After the oral or hypodermic 

 administration of atropine, which presumably cuts out the psychic 

 responses, in 12 cases the quantity removed varied from 15.5 c.c. 

 to 64 c.c, with an average of 37.6 c.c. a difference of 85.4 c.c. on 

 the average or in other words of 69.2 per cent, (more than two 

 thirds). 



(d) There is evidence to believe that the chemical secretion is 

 induced at a very early period, and probably occurs well in the first 

 hour. 



(e) In 12 out of 21 straight experiments without atropine the 

 acidity exceeded a total acid of 70 varying from 74 to 114.5 T. A. 

 0.41 HCL with an average of 97.3 c.c. indicating in over one half 

 the normal psychic responses give an acidity in excess of 70 while the 

 average is equal to or above this point. This finding is supple- 

 mented by the fact that in 14 out of the 21 cases the free acid ex- 

 ceeded 50, the figure frequently given for normal total acidity. 

 These findings in themselves throw an entirely difl:"erent light on the 



