351 
ON THE CERE BRO-VISCERAL NERVE. 
disturbance in the respiratory function, and, sooner or later, 
death. This, as the most evident and palpable effect of the 
division of the nerve, engrossed almost the sole attention of 
physiologists. Its influence on the action of the heart (circula¬ 
tion and respiration are functions nearly connected) was next 
inquired into : but this was an organ suigeneris; it was endowed 
with an inherent principle of contractility; if supplied with 
blood or even with warm fluid, it would beat on, although t ns 
nerve was divided ; nay, although the organ itself was removed 
from the body. At length the influence of this nerve on the 
process of digestion became the subject of inquiry. This is a 
slow process; there is nothing about it that at once arrests the 
attention ; it is merely the gradual change of the food into a 
uniform pulpy mass. I will not detain you, gentlemen, with a 
narration of the numerous experiments instituted by physiologists 
with reference to this function, many of them ingenious, otieis 
without rhyme or reason ; some apparently leading us on to a, 
satisfactory conclusion, and others strangely inconclusive and 
contradictory: some conducted with a spirit of philosophic 
humanity; and others with ad ls^raceful lec e . 
suffering : but I will very briefly give you the ultimate result. 
The Influence of the Cerebro- Visceral Nerve in the Process 
of Disestion— When the cerebro-visceral nerve is divided, and 
not only so, but a portion of it excised, so that the nervous in¬ 
fluence shall be completely cut off from the stomach, digestion, 
or the solution or chymification of the food, is not suspended, but 
only delayed. Those portions which are in contact with the 
villous coat of the stomach become dissolved ; but those that are 
a little within the mass of ingesta, and out of the reach of the 
gastric juice, are unchanged. M. Magendie divided the ce¬ 
rebro-visceral nerves in the thorax and immediately above the 
diaphragm. All disturbance in respiration which might possibly 
produce derangement of digestion was thus avoided, and the 
true influence of the nerve on the functions of the stomach 
would be seen. He says, that, after haying allowed a proper 
period to elapse, the substances were chymifled, and they furnished 
afterwards an abundance of chyle. 
MM. Breschet and Edwards instituted numerous experiments 
to ascertain the kind and degree of nervous influence in the 
process of digestion ; and they arrived at this conclusion, which 
may now, I believe, be taken as a physiological fact, that the 
gastric juice is the solvent principle or agent, and that the 
function of digestion is performed and completed by the different 
portions of food being successively brought into contact with this 
