the secernentia, or sorbentia,
or invertentia.

II. 1. Externally the application of heat, as the warm bath, by its
stimulus on the skin excites the excretory ducts of the perspirative
glands, and the mouths of the lymphatics, which open on its surface, into
greater action; and in consequence many other irritative motions, which are
associated with them. To this increased action is added pleasurable
sensation, which adds further activity to the system; and thus many kinds
of pain receive relief from this additional atmosphere of heat.

The use of a warm bath of about 96 or 98 degrees of heat, for half an hour
once a day for three or four months, I have known of great service to weak
people, and is perhaps the least noxious of all unnatural stimuli; which
however, like all other great excitement, may be carried to excess, as
complained of by the ancients. The unmeaning application of the words
relaxation and bracing to warm and cold baths has much prevented the use of
this grateful stimulus; and the misuse of the term warm-bath, when applied
to baths colder than the body, as to those of Buxton and Matlock, and to
artificial baths of less than 90 degrees of heat, which ought to be termed
cold ones, has contributed to mislead the unwary in their application.

The stimulus of wine, or spice, or salt, increases the heat of the system
by increasing all or some of the secretions; and hence the strength is
diminished afterwards by the loss of fluids, as well as by the increased
action of the fibres. But the stimulus of the warm-bath supplies heat
rather than produces it; and rather fills the system by increased
absorption, than empties it by increased secretion; and may hence be
employed with advantage in almost all cases of debility with cold
extremities, perhaps even in anasarca, and at the approach of death in
fevers. In these cases a bath much beneath 98 degrees, as of 80 or 85,
might do injury, as being a cold-bath compared with the heat of the body,
though such a bath is generally called a warm one.

The activity of the system thus produced by a bath of 98 degrees of heat,
or upwards, does not seem to render the patients liable to take cold, when
they come out of it; for the system is less inclined to become torpid than
before, as the warmth thus acquired by communication, rather than by
increased action, continues long without any consequent chillness. Which
accords with the observation of Dr. Fordyce, mentioned in Sup