200 
ON RUNNET AND CHYMOSINE. 
the contrary, if the acidity of the gastric juice is too great, 
this liquid would exercise too much action on the mucous 
membrane, and the animal would be harassed, &c. 
This theory, it is true, does not explain all the phenomena 
of nutrition ; but it accounts with probability for the use of the 
saliva in digestion ; for it appears impossible to admit the 
principle, that the free soda of the saliva acts as a solvent of 
the aliments, since, as in man, these matters remain but a 
short time in the mouth, and pass without stopping into the 
stomach, where they meet an excess of hydrochloric acid, 
and the alkalies cease to remain uncombined. For those 
animals, which like the Ruminatia, have several cavities, in 
which the aliments remain, this explanation is more easy of 
adoption, but as the food of these animals are of difficult di- 
gestion, it is necessary to retard its entry into the stomach, 
that it may be the more effectually divided and softened, be- 
fore it is offered to be converted into chyme, and these macera- 
tions do not sustain the dissolving theory, although supported 
by the solution of vegetablealbumen, since this solution takes 
place, according to the experience of the laboratory, without 
the presence of an alkali. 
In the Gallinacese, &c, the' nutritive matters remain a long 
time in the crop, before they penetrate the gizzard, and in 
their passage meet with an acid liquor only. 
This theory, which is corroborated by the use of sea salt 
in the preparation of our aliments, by its well established di- 
gestive action, and by the presence of hydrochloric acid, and 
chloride of soda in all stomachs, explains also in an indirect 
manner the action of bi-carbonate of soda in difficult diges- 
tion ; for this salt acts upon the acid, by means of its base, 
and by the resulting chloride of soda, and not by a solvent ac- 
tion, since this is not more probable than the solvent action of 
the saliva in mastication. 
Journ. de Pharm. 
