LACTIC ACID THE NORMAL ACID OF THE STOMACH. 161 
" Still more recently, Messrs. Bidder and Schmidt declare, 
as the result of eighteen corresponding analyses, *that pure 
gastric juice of carnivora, after eighteen to twenty hours’ 
fasting, contained free hydrochloric acicl only , without a trace 
of lactic or any other organic acid; while the gastric juice of 
herbivora contains, with free hydrochloric acid, small quanti- 
ties of lactic acid, which may, however, be referred to their 
more amylaceous food.’* Grunnewald’s experiments led him 
to the conclusion that the acid was an organic one ; while 
Schroeder maintains that the fluid obtained by irritating the 
stomach by peas, owed its reaction to hydrochloric acid.j* 
“ Amidst all this conflict of opinion, a reconciliation is 
scarcely to be hoped for; it is suggested, however, that a 
portion of it, at least, may be owing to the variety of animals 
experimented upon, and the question may be asked, whether 
observations made upon the human subject in the healthy 
condition, should not be relied upon, rather than those derived 
from experiments performed upon lower animals, in whom 
the severity of the operation, and the emotions necessarily 
excited thereby, must unavoidably vitiate the results. The 
difficulty is somewhat relieved by the fact that only two acids 
are involved in the question, and it narrows itself to the 
decision as to whether they are both present together, or 
whether one substitutes the other. The following experi- 
ments may serve to decide this* question. 
ff May 6th, 18o6, at 10 a.m. — Two ounces of dry wheat 
bread were given to St. Martin, which he masticated delibe- 
rately and swallowed. At 12|- p.m. the contents of the 
stomach were removed by Dr. Bunting, in the presence of a 
number of medical gentlemen and students, and carefully 
preserved for immediate analysis. The reaction was decidedly 
acid, sp. gr. 1009. Microscopic examination showed large 
epithelial cells, mucous corpuscles, amorphous granular 
matter, and starch granules, some broken down, others per- 
fect, together with a few cells of cylinder epithelium. 
“Experiment 1. — A portion of the fluid thus obtained was 
subjected to distillation. In the early vapour that came over, 
no trace of acidity could be detected by litmus paper ; the 
distillate was neutral, neither acid nor alkaline, and did not 
precipitate with nitrate of silver. The distillation being 
carried further, so as to concentrate the material in the retort 
and increase its temperature, the distillate was found to become 
acid, and a portion being added to a solution of nitrate of silver, 
* ‘ Cyclopedia of Anat. and Phys.,’ part, xlvii, Art. Stomach and 
Intestines. 
f ‘ Dissert. Inaug . 5 
xxx. 22 
