The appetite gastric juice lowers the freezing-point from -0.550 C. to -0.620 C; the continuous secretion from -0.470 C. to -0.52° C; the fluid of the empty stomach from -0.210 C. to -0.410 C. The juice found in the empty stomach exhibits the greatest fluctuations in osmotic pressure, the appetite and the hunger juice being very constant. The hunger juice has, on the whole, a lower osmotic concentration than the appetite juice.
The foregoing figures for the appetite gastric juice of Mr. V. are practically identical with those reported on the pure gastric juice of other human fistula cases. Sommerfeld (in a ten-year-old girl) found the freezing-point to vary from -0.470 C. to -o. 650 C; Kaznelson (twenty-five-year-old girl) reports a variation from -0.460 C. to -0.540 C. Umber reports two tests on the gastric juice (pure) of a fifty-nine-year-old man with cancer, finding a variation of -0.15° C. to -0.820 C. Assuming that Umber's determinations are correct, the gastric juice of this cancer patient was clearly not normal. We question whether the normal stomach can secrete a juice with an osmotic concentration so much greater than the blood as the figure -0.820 C. demands. The reader will note that the figures of Sommerfeld and Kaznelson, as well as our own for Mr. V., indicate an osmotic pressure of the appetite gastric juice not far below or above that of the human blood. According to Bickel the gastric juice (ten-year-old child) is always hypotonic to the blood. Lehman concludes that the osmotic pressure of normal gastric juice (gastric content) is usually less than - 0.500 C, and that a concentration above this figure indicates hyperacidity or other pathological conditions. This view is obviously untenable.
The osmotic concentration of the dog's appetite gastric juice is practically identical with that of man. Sasaki reports a variation from - 0.51° C. to -0.600 C; Rosemann gives somewhat higher figures, or -0.56° C. to -0.640 C. On the other hand, Bickel reports extraordinary fluctuations in osmotic concentration of dogs' gastric juice (Pavlov pouch) or - 0.520 C. to -1.210 C. We question whether the normal stomach can secrete a juice of the osmotic concentration -1.210 C, that is, twice that of the blood.