General Principles of Physiology. 97 
times of‘examination; whereas inthe undisturbed animal it abated 
uniformly. I speak with the more certainty of the result of these 
experiments, because while I was making them in Worcester, 
Dr. Hastings, without my knowledge, was making similar expe- 
riments at Edinburgh. He has shewn me the detail of several, 
from which it appears that throwing air into the lungs of the 
dead rabbit about fifteen times in a minute, occasions it to cool 
more slowly. In one of his experiments, so great was the effect, 
that while the rabbit, which was left undisturbed, cooled 7.5°, 
that which was subjected to artificial respiration, cooled only 4°. 
He also frequently saw the thermometer rise a little in those 
animals in which the lungs were inflated after death. In those 
in which they were not inflated, the cooling was uniform. 
Thus it appears that the nervous as well as the muscular 
power is capable of performing its functions after the sen- 
sorial power is withdrawn. That power, like the muscular, 
therefore, has no direct dependence on the sensorial power. It 
remains for us to inquire whence it arises that neither of these 
powers ever long survive the sensorial power. 
On the sensorial power being withdrawn, respiration always 
ceases. M. le Gallois finds a great difficulty in explaining why 
respiration should cease on the removal of the brain. 
“ Il est donc certain que Ja vie de tronc n’a son principe im- 
médiat ni dans le cerveau, ni dans aucun des viscéres de la 
poitrine et de abdomen; mais il ne l’est pas moins, que tous 
ces viscéres sont indispensables a son entretien. Or, en con- 
sidérant sous quel rapport ils le sont, les faits énoncés plus haut 
prouvent évidemment que, quant au cerveau, les phénoménes 
mécaniques de la réspiration, c’est-d-dire, les mouvemens par 
lesquels l’animal fait entrer l’air dans ses poumons, dépendent 
immédiatement de ce viscére. Ainsi c’est’ principalement en 
tant que l’entretien de la vie dépend de la réspiration qu’il de- 
pend du cerveau; ce qui donne lieu & une grande difficulte. 
Les nerfs diaphragmatiques, et tous les autres nerfs des muscles 
qui serve aux phénoméines mécaniques de la réspiration, pren- 
nent naissance dans la moélle épiniére, de la méme maniére 
