282 



PHILIP B. HAWK 



which follows the introduction of water is directly proportional to the 

 volume of water employed. This point is shown in the following data 

 taken from one of their tests: 



300 c.c. water - 7.2 c.c. gastric juice 

 500 c.c. water = 17.7 c.c. gastric juice 

 750 c.c. water = 25.7 c.c. gastric juice 



Chighin had previously shown a similar proportionality. The ob- 

 servations mentioned were made by the use of the Pavlov pouch. 



The first experiments showing water to be a gastric stimulant in the 



human stomach were made in the 

 writer's laboratory (Wills and Hawk). 

 The ingestion of water at meal time 

 by two men was accompanied by an 

 increase in the excretion of ammonia 

 which was directly proportional to 

 the extra volume of water ingested. 

 Inasmuch as certain experiments have 

 demonstrated that water stimulates the 

 flow of an acid gastric juice and as 

 certain other experiments have demon- 

 strated that the formation of acid in 

 the body or the introduction of acid 

 from without produces an increase in 

 the urinary ammonia excretion, we 

 feel justified in assuming that the 

 increase in the ammonia excretion ob- 

 served in our experiments was due 

 directly to the stimulation of gastric 

 secretion by the ingested water. That 

 the increase in the ammonia excretion 

 did not arise from intestinal putrefac- 

 tion was indicated by the finding of 

 lowered indican values during the 

 period of high water ingestion. These 

 observations were verified by Ivy (a) in experiments on dogs. 



Since these observations gave only "indirect" data, the problem was 

 reinvestigated in the writer's laboratory and "direct" evidence of stimula- 

 tion obtained. In the latter investigation (Bergeim, Rehfuss and Hawk), 

 water was introduced into the stomachs of normal men and samples of 

 gastric contents removed at intervals of ten minutes by means of the 

 Rehfuss tube (Rehfuss) and analyzed according to the fractional method 

 of gastric analysis (Hawk (g] ). Figure 1 illustrates a pronounced case of 

 water stimulation of gastric secretion, and Figure 2 illustrates a'stimula- 



Fig. 1. Curve showing pronounced 

 stimulation by water and rapid 

 emptying of the stomach. (Berg- 

 eim, Rehfuss and Hawk; Jour. 

 Biol. Chem., 1914, XIX, 345.) 



