mes by reverse sympathy?--1st, When any
irritative motion ceases, or becomes torpid, which was before in perpetual
action; it is either deprived of its usual stimulus, and thence the
sensorial power of irritation is not excited; or it has been previously too
much stimulated, and the sensorial power has been thus exhausted.

In the former case an accumulation of sensorial power soon occurs, which is
excitable by a renewal of the stimulus; as when the fingers, which have
been immersed some time in snow, are again exposed to the usual warmth of a
room. Or, secondly, the sensorial power of irritation becomes so much
accumulated, that the motions, which were torpid, are now performed by less
stimulus than natural; as appears by the warmth, which soon occurs after
the first chill in going into frosty air, or into the bath at Buxton, which
is about eighty degrees of heat. Or, lastly, this accumulation of the
sensorial power of irritation so far abounds, that it increases the action
of the next link of the associated train or tribe of motions; thus on
exposing the skin to cold air, as in walking out in a frosty morning, the
actions of the stomach are increased, and digestion strengthened.

But where the torpor of some irritative motion is owing to the previous
exhaustion of the sensorial power of irritation by too great stimulus, the
restoration of it occurs either not at all, or much more slowly than in the
former instances; thus after intoxication the stomach is very slow in
recovering its due quantity of the sensorial power of irritation, and never
shews any accumulation of it.

2. When an associate motion, as described in the introduction to Class IV.
1. 1. acts with less energy, the sensorial power of association is either
not sufficiently excited by the preceding fibrous motions; or it has been
expended or exhausted by the too violent actions of the preceding fibrous
motions. In the former case there occurs an accumulation of the sensorial
power of association; exactly as, where the usual stimulus is withdrawn,
there occurs an accumulation of the sensorial power of irritation. Thus
when the actions of the capillaries of the skin are diminished by immersion
in cold water, the capillaries of the lungs are rendered torpid by the want
of the excitement of the sensorial power of association, owing to the
lessened actions of the previous fibrous motions, namely, of those of the
skin. Nevertheless as soon as the capillaries of t