140 Prof. B. Moore. On Free Hydrochloric Acid [Feb. 28, 
cases of carcinomatous stomach dilatation, disappeared as such, being 
neutralized by salts of organic acids present, and setting free an equivalent 
amount of these organic acids. 
Further, these authors stated that they had observed cases of great dilata- 
tion, without carcinoma, accompanied by absence of absorption and retention 
of food in the stomach, as great as in the cases of carcinoma cited by them ; 
yet in these cases of dilatation unaccompanied by carcinoma soon after 
n gestion of food there was plenty of free hydrochloric acid present. 
In the literature subsequent to this period one finds chiefly records of a 
smaller number of cases, often of one case only, where regarded from the 
point of view of diagnosis, the absence of hydrochloric acid demonstrated 
the presence of malignant disease where the other signs were obscure; or, 
contrariwise, the presence of free hydrochloric acid was shown where there was 
undoubted malignant disease. 
It is now well established that free hydrochloric acid 1s not absent in 
every case of cancer of the stomach, and also that it may be absent in other 
conditions than cancer, but the percentage of cases of cancer of the stomach 
in which it is absent is so large, that, taken in conjunction with other signs, 
it is a valuable aid in cases of doubtful nature. Thus Osler* records that in 
94 cases in which the stomach contents were examined, in 84 free hydro- 
chloric acid was absent; and v. Jakscht in 17 cases found free hydrochloric 
acid, either absent, or only present in traces, in 14 cases. 
The variations in results obtained by the earlier observers are due in part 
to the employment of different indicators of varying degrees of delicacy, and 
partly to the fact that the attention of these observers was turned almost 
wholly upon entire absence of the free acid as a diagnostic sign, so that little 
care was given to quantitative determinations of the variations in amount of 
the acid, or the relationship of this to the disease, which are far more important 
points. 
If with the improved means for testing the matter both qualitatively and 
quantitatively now at our disposal, the extensive series of observations made 
by earlier workers were now repeated, it would probably be found, on the one 
hand, that in the long series of cases where the free acid was always found 
to be absent, there were in a certain number of cases traces present which 
were missed by the methods employed, and on the other hand, that in those 
series where in the majority of cases free hydrochloric acid was found to be 
present, the tests were given by larger amounts of organic acid, or the positive 
* ‘Principles and Practice of Medicine,’ 3rd edition, p. 491. 
t+ ‘Klinische Diagnostik innerer Krankheiten,’ 3te Auflage, p. 173. 
