e brain; what happens? First, those motions are exerted
with less energy, which are not immediately necessary to life, as the
locomotive muscles; and those ideas, which are generally excited by
volition; at the same time this deficiency of voluntary motion is different
from that which occurs in sleep; as in that the movements of the arterial
system are increased in energy though not in frequency. Next, the motions
of the alimentary canal become performed with less energy, or cease
altogether; and a total want of appetite to solid food occurs, or sickness,
or a diarrhoea occasioned by the indigested aliment. Then the absorbent
vessels cease to act with their due energy; whence thirst, and pale urine,
though in small quantities. Fourthly, the secerning vessels become affected
by the general diminution of sensorial power; whence all the secreted
fluids are produced in less quantity. And lastly, the sanguiferous canals
feel the general torpor; the pulsations of the heart and arteries become
feeble, and consequently quick; and the capillaries of the skin become
inactive, acquire less blood from the arteries, and are consequently paler
and shrunk.

In this last circumstance of the torpor of the sanguiferous system consists
inirritative fever; as all the others are rather accidental or concomitant
symptoms, and not essential ones; as fewer or more of them may be present,
or may exist with a greater or less degree of inactivity.

2. Now as the capillaries of the skin are exposed to greater varieties of
heat and cold, than the heart and arteries, they are supposed to be more
mobile, that is, more susceptible of torpor or exertion, or to
inflammation, by external stimuli or influences, than the other parts of
the sanguiferous system; and as the skin is more sensible to the presence
of heat, than the internal parts of the body, the commencement of the cold
paroxysms of fever generally either first exists in, or is first perceived
by, the coldness and paleness of the skin; and the commencement of the hot
fits by the heat and redness of it.

3. The accumulation of sensorial power occurs in these organs soonest, and
in greatest quantity, during their quiescence, which were most perpetually
in action during health; hence those parts of the system soonest recover
from torpor in intermittent fever, and soonest fall into the contrary
extreme of increased activity; as the sanguiferous system of the heart and
arteries and capillaries. But