GASTRIC JUICE. . 349 
Gastric Juice. 
Human gastric juice mixed with water or fond may be obtained 
for clinical purposes by the use of a gastric sound or the stomach pump, 
but pure gastric juice cannot be obtained in this way, because when the 
stomach is empty the secretion of gastric juice stops, and can only 
be initiated by the drinking of water or the taking of food. 1 
Notwithstanding the considerable number of cases of gastric fistula 
in man already enumerated, the details as to the quantitative chemical 
composition and physical characteristics of that fluid are very meagre. 
Only one set of complete analyses of the fluid has been carried out by 
Schmidt, and these, along with certain incomplete analyses by other 
observers of the total solids and amount of acid, are all the quantitative 
data we possess. 
In a case of human gastric fistula, observed by 0. Schmidt, 2 
the fluid obtained was clear as water, less acid than dog's gastric juice, 
and had a specific gravity of 1 '0022-1 •0024. It scarcely became clouded 
on heating, and left on evaporation a brownish-yellow deliquescent acid 
residue, which on incinerating left a colourless, neutral, or faintly alkaline 
ash, containing no carbonates. On distilling the liquid, only water 
came over, until the fluid attained the consistency of oil, then traces of 
hydrochloric acid, which became stronger as the process was continued. 
In a case observed by Eichet, in which the oesophagus had been 
occluded by strong alkali, and the gastric fistula was the result of an 
operation, the gastric juice was also colourless, had a faint smell, and 
varied greatly in acidity. 
Pure gastric juice has also recently been obtained by Fremont 3 from 
a fistula in the isolated stomach of the dog. Gastric juice so obtained 
is a limpid, clear, colourless, inodorous, very acid, and powerfully peptic 
fluid, capable of digesting its own weight of coagulated albumin. The 
clog in question weighed 12 kilos., and yielded 800 grms. of gastric 
juice daily. If the secretion takes place at the same rate in the human 
subject, a man weighing 60 kilos. (132 lbs.) should secrete 4 litres 
of gastric juice daily. 
Pure gastric juice may be collected from a Pawlow fistula i twelve to 
fifteen hours after a true meal, by giving the animal a fictitious meal. 
The food which is eaten does not reach the stomach, but drops from 
an oesophageal fistula. The process of feeding induces reflexly an 
abundant secretion of gastric juice, which can be collected in a pure 
condition. A dog will go on feeding voraciously in this manner for 
hours, and in the course of an hour 200-300 c.c. of gastric juice may be 
collected. The animal is said to be unaffected in health by a collection 
of an hour per diem. 
1 This method is of more service clinically than physiologically as a mode of obtaining 
gastric juice in cases of dyspepsia, in order to determine the amount of acidity, and whether 
this is due to a normal amount of hydrochloric acid or to excess of organic acids, the pro- 
duct of bacterial action. See Leube, Sitzungsb. d. phys.-med. Soc. zu Erlangen, 1871. 
Heft 3 ; Kiilz, Deutsche Ztschr. f. prakt. Med., Leipzig, 1875, No. 27 ; C. A. Ewald, 
"Klinik der Verdauungskrankheiten," 1890, Bd. i. S. 87; Gamgee, "Physiological 
Chemistry," vol. ii. pp. 163-178. 
2 The case was that of a healthy woman with a chronic fistula, yielding gastric juice 
freely without apparent effect on the health of the patient. 
3 Demonstrated by Herzen, International Congress, Bern, 1895. 
4 Pawlow and Schoumow-Simanowsky, Centralbl. f. Physiol., Leipzig u. Wien, 1889, 
Bd. hi. S. 113. See article on "Mechanism of Gastric Secretion." 
