THE ACID OF THE GASTRIC JUICE. 361 
juice was an unsolvable riddle. Bui when Thomsen had shown that 
the weakesl arid j s in some measure capable of displacing the strongest 
from its salts, and Mai}' that by a simple process of diffusion this strong 
acid may be afterwards separated, the subject assumed a different aspect. 
It was no Linger necessary for the cell to he endowed with some force 
of sufficient intensity; to directly break up such stable substances as the 
alkaline chlorides. All that was necessary was that the cell should be 
able from the organic material at its disposal to form an organic acid, 
and afterwards to rapidly excrete the small fraction of hydrochloric 
acid formed by the interaction between this organic acid and the neutral 
chlorides, so that a fresh quantity of hydrochloric acid may he formed 
by the mass action of the remainder of the organic acid on the remainder 
of the chlorides. The organic salts so formed can then decompose by 
cell activity into organic acid and base again, and the base be returned to 
the blood stream. Since gastric juice is not accompanied by an organic 
acid, this must he retained in the cell and induce a continuous cyclic 
change. It is thus possible, with the aid of the new facts of physical 
chemistry, to see that the process of secretion of hydrochloric acid can 
be reduced to the same level as that of the secretion of any organic 
material. 
This, however, is but a small portion of the entire problem. As Bunge 
says : "In the appearance of the free hydrochloric acid lies nothing puzzling. 
Puzzling only is the power of the epithelial cell to send the hydrochloric acid 
freed from the sodium chloride streaming always in one direction toward- the 
lumen of the gland, and the sodium carbonate 1 simultaneously formed always 
back in the opposite direction towards the lymph and blood channels. But 
such a puzzle we meet everywhere in the living tissue. Every cell possesses 
the power to dispose of material in a suitable manner, attracting or repelling 
it and sending it streaming in different directions." -' 
Maly's theory. — Maly has attempted to build on a purely physical 
basis a theory of the formation of hydrochloric acid from the chlorides of 
the blood, of which the following are the outlines : 3 — 
1. There are no theoretically alkaline salts in the blood. Blood 
plasma owes its alkalinity to two theoretically acid salts, di-sodic 
phosphate (Xa. 2 HP0 4 ), and sodium bicarbonate (XaHCO,); besides 
these two acid salts plasma contains excess of carbonic acid. 
2. Disodic phosphate in presence of calcium chloride forms some 
free hydrochloric acid, thus :— 3CaCL+2Xa,HP0 4 = Ca..(P0 4 ).,+4Xa('l+ 
2HC1. 4 
Chiefly from the facts above stated, Maly supposes that by the 
interaction of these theon tically acid salts of the plasma, on the chlorides 
present with them in solution, traces of hydrochloric acid are formed : 
these traces of hydrochloric acid are rapidly removed, on account of the 
high diffusibility of hydrochloric acid, 5 by the gland-cells which act as a 
1 Bunge is considering the hydrochloric acid as set free by the action of carbonic acid. 
2 Somewhat freely translated from Bunge, " Lehrbuch der phvsiol. Chemie," Leipzig, 
1894, Aufl. 3, S. 148. 
3 Abstracted from Maly, Hermann's "Handbuch," Bd. v. (2), S. 66. 
4 R. Pribram. Jahresb. ii. d. Fortsehr. d. Thicr-Chcm.. Wiesbaden, 1871, Bd. i. 8. 107 ; 
Gerlaeh. ibid., 1873, Bd. iii. S. 109. 
5 Graham has shown that the free acids diffuse more rapidly Than their sails ; HC1 
diffusing thirty-four times as rapidly as NaCl. Graham was also the first to show that, by 
diffusion of acid potassium sulphate, sulphuric acid was obtained in the dialysate, while 
normal sulphate remained behind. 
