1869.] Free Hydrochloric Acid in the Gastric Juice. 



393 



with alternate agitation, it required, as might be inferred, several repetitions 

 before the peroxide with its phosphoric acid became a permanent precipi- 

 tate, and still several more before the precipitate of phosphate of lime 

 became permanent. 



In my earlier experiments, in which I employed parchment- paper, I was 

 embarrassed with the presence of sulphate of lime in the precipitated powder ; 

 so that what was at first supposed to be phosphates of lime and iron was 

 fouud to be in part sulphate of lime. This sulphate was due to imperfectly 

 washed parchment-paper, which still contained sulphuric acid. This diffi- 

 culty overcome, the experiments were made with parchment-paper pre- 

 pared from German and Swedish filter-paper, as well as with goldbeater's 

 skin (animal membrane). 



I employed acid phosphate of the formula above, with (each by itself) 

 chloride of sodium, chloride of ammonium, chloride of potassium, chloride 

 of calcium, and chloride of magnesium. 



I also experimented with acetate of potassa and acid phosphate of 

 lime. 



With all of these there was obtained the same kind of evidence of increased 

 acidity on one side and of increased alkalinity on the other, to wit, the 

 powder thrown down from the mixture of acid phosphate and chloride. 

 What successive additions of ammonia had been required to effect, had been 

 accomplished by dialysis. 



The same effect took place from a mixture of acid phosphate of soda and 

 chloride of calcium. 



It follows from the above, if these experiments fairly represent the case, 

 and from the known composition of the blood, its condition in the walls of 

 the stomach, and the structure of the gastric tubules, that free or uncom- 

 bined hydrochloric acid must find its way into the bottoms of the gastric 

 tubules, and thence into the cavity of the stomach. 



It may be urged that I should show that the acid phosphate pressed from 

 the corpuscles more than neutralizes the alkalinity of the plasma present. 

 In reply it may be said that I present a condition of things in which there 

 is the kind of physical change required going on, namely, relative augmen- 

 tation of the corpuscles, under pressure, the concomitant of increased supply 

 of blood to the gastric mucous membrane. Its degree must be inferred 

 from the effects on the secretions, which I have endeavoured to point out, 

 by conducting an experiment under what I conceive to be essentially like 

 conditions, and obtaining the result due to identical conditions. 



The secretion of hydrochloric acid is of course mixed with acid phosphates 

 and alkaline chlorides. 



That such a result as I have arrived at would follow experiment might 

 have been predicted from Graham's researches on dialysis. Phosphates of 

 lime and soda are colloidal relatively to more crystalloidal hydrochloric 

 acid. Graham found that bisulphate of potassa, by dialysis, was resolved 

 into two salts or mixtures of greater and lesser acidity than the original bi- 



