gth.
Put much more white arsenic reduced to powder into a given quantity of
distilled water, than can be dissolved in it. Boil it for half an hour in a
Florence flask, or in a tin sauce-pan; let it stand to subside, and filter
it through paper. My friend Mr. Greene, a surgeon at Brewood in
Staffordshire, assured me, that he had cured in one season agues without
number with this saturated solution; that he found ten drops from a
two-ounce phial given thrice a day was a full dose for a grown person, but
that he generally began with five.

9. The manner, in which arsenic acts in curing intermittent fevers, cannot
be by its general stimulus, because no intoxication or heat follows the use
of it; nor by its peculiar stimulus on any part of the secreting system,
since it is not in small doses succeeded by any increased evacuation, or
heat, and must therefore exert its power, like other articles of the
sorbentia, on the absorbent system. In what manner it destroys life so
suddenly is difficult to understand, as it does not intoxicate like many
vegetable poisons, nor produce fevers like contagious matter. When applied
externally it seems chemically to destroy the part like other caustics.
Does it chemically destroy the stomach, and life in consequence? or does it
destroy the action of the stomach by its great stimulus, and life in
consequence of the sympathy between the stomach and the heart? This last
appears to be the most probable mode of its operation.

The success of arsenic in the cure of intermittent fevers I suspect to
depend on its stimulating the stomach into stronger action, and thus, by
the association of this viscus with the heart and arteries, preventing the
torpor of any part of the sanguiferous system. I was led to this conclusion
from the following considerations.

First. The effects of arsenic given a long time internally in small doses,
or when used in larger quantities externally, seem to be similar to those
of other great stimuli, as of wine or alcohol. These are a bloated
countenance, swelled legs, hepatic tumours, and dropsy, and sometimes
eruptions on the skin. The former of these I have seen, where arsenic has
been used externally for curing the itch; and the latter appears on
evidence in the famous trial of Miss Blandy at Chelmsford, about forty
years ago.

Secondly. I saw an ague cured by arsenic in a child, who had in vain
previously taken a very large quantity of bark with great regularity. And