Honigmann and von Noorden1 advised that the amount of combined hydrochloric acid in cases in which free acid is lacking be determined by the amount of decinormal standard hydrochloric-acid solution required, in order to give a positive reaction for free hydrochloric acid, or they really determined the deficit of hydrochloric acid which exists in the filtrate, in order to combine with all the proteids. The more of the decinormal hydrochloric-acid solution it is necessary to add in order to give a positive reaction for free acid, the less the amount of combined hydrochloric acid in the filtrate. I do not think that this procedure is very important, for the degree of acidity alone already gives us a sufficient clew as to this condition. Moreover, the amount of peptone and propeptone qualitatively found in the filtrate will also indicate the greater or smaller amount of combined hydrochloric acid. If there is no combined hydrochloric acid whatever, then there will be no biuret reaction present.

During the last six or seven years a host of methods have been described, serving the purpose of determining analytically either the free and the combined hydrochloric acids or the chlorides. We need only mention the methods of Sjoequist,2 Martius and Luettke,2 and the above-described procedures of Hehner-Seemann1 and Hayem-Winter.2 All of these are quite complicated and far from being exact. It has been found that the gastric contents include considerable quantities of ammonia (NH8) in the form of ammonium chloride (NH4C1). All the methods mentioned are based on results obtained under the application of heat, notwithstanding the fact that the latter will lead to the evaporation of ammonia and the formation of free hydrochloric acid. The error which thus arises merely from this circumstance exceeds ten per cent (Rosenheim,3 H. Strauss,4 and others). But besides the errors of these analytical methods, it has been found by the most eminent authors that in reference to treatment and diagnosis we do not derive from these tests any more data than from the simple method of titration and determination of free hydrochloric acid (Honigmann,5 Von Noorden,6 H. Strauss, Rosenheim). For this reason I did not think it necessary to give a detailed account of all analytical methods.

For practical purposes the determination of the total acidity (A=aciditas), of free hydrochloric acid (L=acidum hydrochloricum liberum), and the qualitative test for lactic acid as above detailed will suffice. In some instances Leo's method may also be applied; in this way the quantity of combined hydrochloric acid (C=acidum hydrochloricum combinatum) and the quantity of acid salts may be ascertained.

1 Honigmann und von Noorden: Zeitschrift f. klin Medicin, Bd.

2Sjoequist: L. c.

3Martius and Luettke: "Die Magenstture des Mensclien/ Stuttgart. 1892.

1Seemann: Zeitschr. f. klin. Medicin, vol. 5, p. 272. 2 Hayem et Winter: "Du Chimisme Stomachal," Paris, 1891, p. 72.

3Th. Rosenheim: Centralbl. f. klin. Medicin, 1892, No. 89. 4H. Strauss: Berl. klin. Wochenschr., 1893, No. 17. 5 Honigmann: Berl. klin. Wochenschr., 1898, Nos. 15 and 16. 6C. vonNoorden: Berl. klin. Wochenschr., 1893, No. 18.

Contra-Indications To The Use Of The Stomach Tube

The application of the tube is not advisable in cases of recent hemorrhages, no matter whether from the stomach or from the lungs, in all cases of fresh ulcers of the stomach, aortic aneurism, and in markedly cachectic and debilitated persons. In cases in which there is a mere suspicion of an ulcer, some authors employ the soft-rubber tube, while others are opposed to its application.