1910. | Hydrochloric Acid in the Gastric Tubules. 89 
(cf. p. 63), but the results obtained were of an indefinite nature, although 
indicating the presence of acid. The rabbit and the guinea-pig were the 
animals used. In the experiment with the rabbit, the animal was killed by 
chloroform, and portions of the gastric mucosa (fresh) were teased in a 
saturated aqueous solution of tropeolin, or in a saturated glycerine solution 
(25 or 50 per cent.). A red colour was observed in the region of the mucosa 
containing the peptic glands. 
With the guinea-pig, the tropeolin was injected subcutaneously as a 
saturated solution made up in either distilled water or in Ringer’s solution. 
The amount injected varied from 18 to 22 c. cms., and was administered by 
two injections in the abdominal region, at intervals varying from 1 to 
14 hours, or from 2 to 24 hours. The duration of the experiment varied 
from 4 to 54 hours. The reagent, both in aqueous solution and when 
dissolved in Ringer’s fluid, exerted a decidedly toxic influence, and _ its 
presence in the body appeared to cause the animals considerable discomfort. 
The contents of the stomach were in a very watery condition, and much gas 
was present both in the stomach and intestines. Inflammatory conditions 
supervened at the site of inoculation. The urine on some occasions 
gave the characteristic rose-coloured reaction on the addition of concen- 
trated hydrochloric acid, but not on the addition of a 0°5 per cent. solution. 
Death was produced by shock. On opening the stomach a rose-coloured 
area was observed on the surface of the mucosa near the cesophageal opening 
and in the region corresponding to the border of the lesser curvature. In 
the guinea-pig injected with the reagent dissolved in Ringer’s fluid, a rose 
colour was also observed in the pyloric region. It extended across the 
mucosa of the superior half of the organ in this region, and was visible also 
on the surface of the mucosa of the duodenum adjacent to the orifice of the 
pylorus. Portions of the gastric mucosa were teased and examined in 50 per 
cent. glycerine without delay, but owing to the general distribution and 
diffuseness of the rose colour in the gland tubules, no positive information 
as to the occurrence of the acid within any one type of cell was obtained by 
this method. 
The drawings accompanying the paper were made with the aid of an Abbé 
camera lucida (Zeiss or Leitz) with a Zeiss microscope, compensating ocular 
No. 4 (Zeiss) or No. 2 (Leitz), and Leitz objectives No. 3 or one-twelfth oil 
immersion. The drawing paper was laid flat on the table or on a board placed 
on a level with the stage of the microscope. The drawings illustrating the 
results obtained in the Prussian blue experiments were mostly made from 
unstained preparations. In some cases, illustrations of which have not been 
included, the sections were stained with a 0°5-per-cent. aqueous solution of 
VOL. LXXXIII.—B. H 
