98 Dr. A. P. W. Philip on the 
que ceux de tous les autres muscles de tronc. Comment se 
fait-il donc qu’aprés le décapitation, les seuls mouvemens in- 
spiratoires soient anéantis, et que les autres subsistent? C’est 
14 4 mon sens, un des grands mystéres de la puissance nerveuse; 
mystére qui sera dévoilé tét ou tard, et donc la découverte 
jettera la plus vive lumiére sur le mécanisme des fonctions de 
cette merveilleuse puissance.” 
This difficulty appears to me to arise from M. le Gallois’s 
having regarded respiration as a function wholly dependent on 
a combination of the nervous and muscular powers ; whereas it 
seems evident, I think, that the sensorial power also shares in 
it. The muscles of respiration are, in the strictest sense, mus- 
cles of voluntary motion ; we can at pleasure interrupt, renew, 
accelerate, or retard their action; and if we cannot wholly pre- 
vent it, it is for the same reason that we cannot prevent the 
action of the muscles of the arm, when fire is applied to the 
fingers. The pain, occasioned by the interruption of a supply of 
air to the lungs, is greater than can be voluntarily borne. Re- 
spiration continues in sleep for the same reason that we turn our- 
selves in sleep when our posture becomes uneasy. It continues 
in apoplexy for the same reason that the patient generally moves 
his limbs if they are violently irritated. If respiration continues 
in apoplexy when no irritation of the limbs, however violent, 
excites the patient to move them, it arises from the interruption 
of a supply of air to the lungs producing a greater degree of 
irritation than we are able to produce by other means. As the 
insensibility increases in apoplexy, the breathing becomes less 
frequent; and when the former becomes such that no means 
can longer excite any degree of feeling, the breathing ceases. 
By a certain sensation a desire is excited to expand the chest. 
This is an act of the sensorium. Till this act take place, both 
the nervous and muscular powers, by which its expansion is ef- 
fected, are inert; it is in vain that these powers exist, if the power 
which calls them into action be lost. Thus the removal of the 
brain puts a stop to respiration. 
Is it said that the motions of respiration must be involuntary, 
because we are in general unconscious of them? but do we not 
