r a common fire. By occasionally adding more and more chalk,
carbonic acid gas might be carried through a tin pipe from the arm of the
iron pot to any part of the room near the patient, or from an adjoining
room. In the same manner a diffusion of solution of flowers of zinc might
be produced and breathed by the patient, and would be likely much to
contribute to the healing of pulmonary ulcers; as observed by Mr. Watt. See
the treatise above mentioned.

Breathing over the vapour of caustic volatile alkali might easily be
managed for many hours in a day; which might neutralize the acid poison
formed on pulmonary ulcers by the contact of oxygen, and thus prevent its
deleterious quality, as other acids become less caustic, when they are
formed into neutral salts with alkalis. The volatile salt should be put
into a tin canister, with two pipes like horns from the top of it, one to
suck the air from, and the other to admit it.

[Illustration]

Secondly, the external ulcers in scrophulous habits are pale and flabby,
and naturally disinclined to heal, the deposition of fluids in them being
greater than the absorption; these ulcers have their appearance immediately
changed by the external application of metallic calxes, and the medicines
of the article Sorbentia, such as cerussa and the bark in fine powder, see
Class I. 2. 3. 21. and are generally healed in a short time by these means.
Induced by these observations, I wished to try the external application of
such powders to ulcers in the lungs, and constructed a box with a
circulating brush in it, as described in the annexed plate; into this box
two ounces of fine powder of Peruvian bark were put, and two drams of
cerussa in fine powder; on whirling the central brush, part of this was
raised into a cloud of powder, and the patient, applying his mouth to one
of the tin pipes rising out of the box, inhaled this powder twice a day
into his lungs. I observed it did not produce any cough or uneasiness. This
patient was in the last stage of consumption, and was soon tired of the
experiment, nor have I had such patients as I wished for the repetition of
it. Perhaps a fine powder of manganese, or of the flowers of zinc, or of
lapis calaminaris, might be thus applied to ulcers of the lungs with
greater advantage? Perhaps air impregnated with flowers of zinc in their
most comminuted state, might be a better way of applying this powder to the
lungs, as discovered by Mr. Watt. See Dr. Bed