268 
DR. PHILIP’S OBSERVATIONS ON 
sudden impression made on the nervous system, by which the whole of the 
functions are instantaneously destroyed,) the sensorial functions are the first 
which cease, all the other powers of the system remaining more or less perfect, 
and any imperfection which appears in them not directly depending on the 
loss of the sensorial power. 
Of the sensorial functions, sensation and volition are the only ones which 
we are called upon to consider here, because they alone have any share in 
maintaining animal life. That these functions are essential to the maintenance 
of life in all the more perfect animals, will, I think, appear from what I am 
about to lay before the Society. 
The following may be regarded as the nervous functions properly so called. 
The excitement of the muscles of voluntary motion, by which through the in- 
tervention of the nervous system, they in their usual functions are subjected to 
the sensorial power ; the occasional excitement of the muscles of involuntary 
motion, by which under certain circumstances the sensorial power is also 
capable of impressing them through the nerves, particularly when under the 
influence of the passions ; the act of causing an evolution of caloric from the 
blood, by which the due temperature of the animal body is maintained ; the 
act of forming from the blood the various secreted fluids, and of maintaining 
the other assimilating processes by which the healthy structure of every part 
of the body is preserved. 
The first of these functions is universally acknowledged to be a function of 
the nervous power, properly so called ; but there has been much difference of 
opinion respecting the way in which it operates. The older physiologists be- 
lieved that the muscles derive their power from the nervous system. Haller* 
was the first who taught that the muscular power belongs to the muscle itself, 
to which the nervous power bears no relation but that of a stimulus, and 
endeavoured to support those opinions by experiment. His opponents, however, 
objected to his inferences, because, although the division of the nerves may 
prevent the muscle from receiving more nervous power, it does not deprive it 
of that already bestowed upon it, either existing in the muscular fibres them- 
selves, or dispersed through them in nerves too small to be removed ; and this 
objection appeared to be strengthened by the muscles of involuntary motion, 
* Element. Physiolog. 
