1910.]  Aydrochloric Acid in the Gastric Tubules. 65 
the outer border of the chief cells in the necks of the glands; this he 
interpreted as due to early post-mortem changes permitting the imbibition 
of acid from the stomach contents. Dark blue masses were also found 
filling the lumina of the neck region of the glands in certain places; these 
he regarded as acid ingredients of the stomach and masses of mucus. By 
the same method Sehrwald found that the connective tissue and the walls 
of the blood-vessels became blue, and very frequently the blood corpuscles 
also, enabling even small capillaries to be traced. The production of colour 
in such corpuscles he regarded as due to the small quantity of plasma or 
lymph in their immediate neighbourhood being insufficient to neutralise 
the acid of the iron salt, and thus, when taken up by the cells, coloration 
would be rendered possible. 
This occurrence might also be explained by the supposition that, as regards 
the acid of the iron salt, the absorptive power of certain cellular elements— 
the connective tissue elements, the parietal cells, and certain of the red 
corpuscles included—is so great that, although they were previously 
alkaline in reaction, as a result of this absorption they take on an acid 
character. This, together with the fact of the experiment being based 
on the assumption that the acid reaction of the parietal cells would persist 
throughout the day the sections were allowed to remain in the solution 
of lactate of iron before being placed in one of potassium ferricyanide, 
and that the acid fluid, if present, would not diffuse from, or the alkaline 
fluids of surrounding elements would not diffuse into the parietal cells and 
neutralise any acid present, makes it evident that the results obtained cannot 
be regarded as decisive. 
A criticism similar to the above was passed by Friinkel in 1891,* and he 
further states that if sections of a stomach, hardened for some time in alcohol, 
are placed in a solution of Prussian blue, the same effect is produced that 
Sehrwald regarded as evidence of the formation of acid by the parietal cells. 
Sehrwaldt also made experiments 2m vitro with anilin black, for the purpose 
of deciding whether the differential staining of the parietal cells, observed by 
Griitzner when using this dye, was due to their acid reaction. The latter 
observert had found by treating sections of the stomach fixed in alcohol 
with 1-per-cent. aqueous solution of anilin black, and subsequently with 
bichromate of potassium, that the parietal cells became violet-black in 
colour, while the chief cells were of a dirty grey hue with blackish nuclei. 
He did not interpret this as due to an acid reaction of the parietal cells, 
* S. Frankel, ‘ Pfliiger’s Archiv,’ 1891, vol. 48. 
+ Sehrwald, zbid. 
_ | Griitzner, ‘ Pfliiger’s Archiv,’ 1879, vol. 20. 
VOL: LXXXIT.——B; ; Fr 
