146 Prof. B. Moore. On ree Hydrochloric Acid [Feb. 28, 
hour in order that the precipitate may become granular, filtered through a Gooch 
crucible, dried and weighed. 
From the weight of barium sulphate the amount of total hydrochloric acid (free 
and combined with organic matter) is then calculated. 
In regard to this method, it must be stated that it gives not only the total 
amount of hydrochloric acid free or combined with proteid; but also the entire 
amount of inorganic acid (hydrochloric or other acid possessing a soluble barium 
salt) free or combined with organic matter or a volatile base. 
The amount of such organic salts in normal stomach contents is small, but in 
the carcinoma cases the amount is probably larger. Thus in Cases XI, XVI, and 
XVII, the amount of hydrochloric acid given by this method is out of proportion 
both to the other cases and to the amounts of acid given by the other methods, this 
result can only be explained by the presence of compounds of inorganic acids 
probably hydrochloric, with volatile or organic bases, or with amido acids.* 
This is further shown by the fact that in carrying out the incineration method for 
the determination of total organic acids,t although the titration figure with phenol- 
phthaléin is high, a negative result was obtained. In fact, of 10 ¢.c. of deci-normal 
alkali added in excess in Case XI, 6°6 ¢.c. disappeared, which could only arise from 
the presence in combination with inorganic acid of some organic base. 
(e) Lotal Free and Combined Organic Acids.—An attempt was made to investigate 
this quantity by the following method. ‘Ten c.c. of the filtered gastric contents are 
taken and titrated with phenol-phthaléin as in (a) for determination of total acidity. 
In this process as mentioned above, there are neutralised, the hydrochloric acid, the 
organic acids, and the acid salts (such as acid phosphates). The neutral solution is 
next evaporated to dryness, incinerated, taken up with hot water and boiled. In 
this process the sodium chloride formed from the hydrochloric acid remains 
unaltered, the neutral salts formed from the acid salts remain neutral; but the 
neutral organic salts formed from the organic acids, as well as any neutralised 
organic salts originally present in the gastric contents, are converted into carbonates 
and give an alkaline reaction. Accordingly the total organic acids present in the 
gastric contents, whether free or combined, are given, by now titrating the solution 
with excess of acid, boiling to remove carbonic acid, and back titration with deci- 
normal alkali. 
The results, as given in the table, show that the amount of organic acids present, 
both in the normal controls and in the malignant cases, is very small, in fact, in 
some of the malignant cases, the results yield a negative value.{ As indicated 
under the Morner-Sjéqvist method this, however, indicates the presence of salts of 
organic bases with inorganic acids in the stomach contents, and hence, for both this 
* Determinations in Case XI of the amount of ammonia by Schléssing’s method 
showed that the amount of ammonia is small, so that the acid must be present in 
combination with organic bases. 
t Vide infra. 
jt As shown by the fact that on incineration in the presence of excess of alkali, the 
amount of alkali recovered afterwards was less than that added in excess of amount 
necessary for neutralisation. 
