ON RUNNET AND CHYMOS1NE. 
199 
membrane of the stomach, and this action augments the secre- 
tion of chymosine ; 
That the action of chymosine cannot yet be explained, and 
that, saying that the caseous matter undergoes an isomeric 
change through the influence of chymosine, or that the action 
takes place in consequence of a catalytic force, only sets the 
mind at rest, without explaining the phenomena. 
I have given the name of chymosine to the matter secreted 
by the mucous membrane of the stomach, because this name 
reminds only of chymification ; or the first part of digestion, 
while the word peprine (pepsine ?) recals the idea of diges- 
tion as a whole, that is chymification and chylification; also 
because we perceive the aliments converted into chyme, but 
are notable to detect the passage of chyme into chyle. 
If we may apply to living organs, observations made on 
these organs after the death of the animal, it will be easy to 
explain some parts of the phenomena of digestion. 
When an animal takes into its mouth, nutritive matter, the 
digestive apparatus is excited, the saliva flows, is mixed dur- 
ing mastication with the aliment which its renders alcaline. 
Mastication completed, these matters enter the stomach, meet 
the gastric juiceby which the free soda isconvertedintochloride 
of sodium. This chloride excites the action of the mucous 
membrane and increases the secretion of chymosine, which 
finds a solvent in the excess of hydrochloric acid contained 
in the gastric juice. The matters accumulated in the stomach, 
are agitated by the movements of this organ, penetrated by 
the gastric juice, and gradually converted into chyme, under 
the influence of the temperature, the chymosine and its solvent. 
This operation finished, the chyme passes the pylorus, and 
mixing in the duodenum with the pancreatic and hepatic se- 
cretions, is necessarily modified by their action, previous to 
being offered to the lacteals. If any disease should change the 
chemical nature of the secretion from the mucous membrane 
of the stomach, the chymosine would be without action ; for 
though secreted, it would not meet with a liquid capable of 
precipitating it, and digestion would not proceed properly; on 
