h. At first they have
great anhelation and palpitation of heart at their ingress into cold water;
but by the habit of a few weeks they are able to bear this diminution of
heat with little or no inconvenience; for the power of volition has some
influence over the muscles subservient to respiration, and by its counter
efforts gradually prevents the quick breathing, and diminishes the
associations of the pulmonary vessels with the cutaneous ones. And thus
though the same quantity of heat is subducted from the skin, yet the torpor
of the pulmonary vessels and internal glands does not follow. Hence during
cold immersion less sensorial power is accumulated, and in consequence,
less exertion of it succeeds on emerging from the bath. Whence such people
are esteemed hardy, and bear the common variations of atmospheric
temperature without inconvenience. See Sect. XXXII. 3. 2.

IV. Venesection has a just title to be classed amongst the torpentia in
cases of fever with arterial strength, known by the fulness and hardness of
the pulse. In these cases the heat becomes less by its use, and all
exuberant secretions, as of bile or sweat, are diminished, and room is made
in the blood-vessels for the absorption of mild fluids; and hence the
absorption also of new vessels, or extravasated fluids, the produce of
inflammation, is promoted. Hence venesection is properly classed amongst
the sorbentia, as like other evacuations it promotes general absorption,
restrains haemorrhages, and cures those pains, which originate from the too
great action of the secerning vessels, or from the torpor of the
absorbents. I have more than once been witness to the sudden removal of
nervous head-achs by venesection, though the patient was already exhausted,
pale, and feeble; and to its great use in convulsions and madness, whether
the patient was strong or weak; which diseases are the consequence of
nervous pains; and to its stopping long debilitating haemorrhages from the
uterus, when other means had been in vain essayed. In inflammatory pains,
and inflammatory haemorrhages, every one justly applies to it, as the
certain and only cure.

V. When the circulation is carried on too violently, as in inflammatory
fevers, those medicines, which invert the motions of some parts of the
system, retard the motions of some other parts, which are associated with
them. Hence small doses of emetic tartar, and ipecacuanha, and large doses
of nitre, by producing nausea debil