DR. PHILIP’S OBSERVATIONS ON 
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motion ? It is a muscle whose action under all ordinary circumstances we can 
excite, interrupt, retard, and accelerate at pleasure, but it is not a muscle whose 
action we can at all times controul. There is no such muscle, because the im- 
pression on the sensorium tending to call any particular set of muscles into 
action may be so powerful, that we are unable to controul it. Who can pre- 
vent the action of the muscles of the arm when fire is suddenly applied to the 
fingers ? Neither do we mean by the term muscle of voluntary motion, one 
which we cannot call into action during sleep. If our posture during sleep 
becomes uncomfortable, we call the muscles both of the trunk and limbs into 
action for the purpose of changing it. The uneasiness caused by the continu- 
ance of the same posture, sufficiently rouses the sleeper to make him will a 
change of posture, without rendering him at all more sensible to other impres- 
sions of a slighter nature, and his sleep continues. 
What muscles then are more under command than those of respiration ? 
We can on all usual occasions interrupt, renew, retard, or accelerate their 
action at pleasure ; and if we cannot interrupt it for as long a time as that of 
the muscles of a limb, this depends on no peculiarity in the action of these 
muscles, but on the nature of the office they are called on to perform ; and if 
we excite them in sleep for the removal of an uneasy sensation, and cannot 
controul them under a sense of suffocation, that is, in a state of greater suffer- 
ing than we can voluntarily bear, all this is no more than applies to every other 
muscle of voluntary motion : but from the nature of our constitution we must 
breathe many times every minute, and we need not turn ourselves more than 
once in many hours, — a difference depending on circumstances which have 
nothing to do with the nature of the muscles we employ in either of these acts. 
If we find the breathing going on in apoplexy after all voluntary motion 
of the limbs lias ceased, it is because the sensation exists which calls on the 
patient to inflate his lungs, while there is none which calls for the action of the 
limbs. In the slighter states of apoplexy if the limbs be much irritated, the 
muscles which move them will also be called into action ; and in the severer 
states, if the patient breathes, when no irritation of the limbs can excite him to 
move them, it is that the want of wholesome air in the lungs, after a certain 
interval, produces a more powerful impression than any other means we can 
employ. People have voluntarily held the hand in the fire, but no man ever 
