RVATIONS ON THE SORBENTIA.

I. 1. As there is great difference in the apparent structure of the various
glands, and of the fluids which they select from the blood, these glands
must possess different kinds of irritability, and are therefore stimulated
into stronger or unnatural actions by different articles of the materia
medica, as shewn in the secernentia. Now as the absorbent vessels are
likewise glands, and drink up or select different fluids, as chyle, water,
mucus, with a part of every different secretion, as a part of the bile, a
part of the saliva, a part of the urine, &c. it appears, that these
absorbent vessels must likewise possess different kinds of irritability,
and in consequence must require different articles of the materia medica to
excite them into unusual action. This part of the subject has been so
little attended to, that the candid reader will find in this article a
great deal to excuse.

It was observed, that some of the secernentia did in a less degree increase
absorption, from the combination of different properties in the same
vegetable body; for the same reason some of the class of sorbentia produce
secretion in a less degree, as those bitters which have also an aroma in
their composition; these are known from their increasing the heat of the
system above its usual degree.

It must also be noted, that the actions of every part of the absorbent
system are so associated with each other, that the drugs which stimulate
one branch increase the action of the whole; and the torpor or quiescence
of one branch weakens the exertions of the whole; or when one branch is
excited into stronger action, some other branch has its actions weakened or
inverted. Yet though peculiar branches of the absorbent system are
stimulated into action by peculiar substances, there are other substances
which seem to stimulate the whole system, and that without immediately
increasing any of the secretions; as those bitters which possess no
aromatic scent, at the head of which stands the famed Peruvian bark, or
cinchona.

2. Cutaneous absorption. I have heard of some experiments, in which the
body was kept cold, and was thought to absorb more moisture from the
atmosphere than at any other time. This however cannot be determined by
statical experiments; as the capillary vessels, which secrete the
perspirable matter, must at the same time have been benumbed by the cold;
and from their inaction there could not have been the us