another case of a young officer, who had lived intemperately, and laboured
under an intermittent fever, and had taken the bark repeatedly in
considerable quantities, with a grain of opium at night, and though the
paroxysms had been thrice thus for a time prevented, they recurred in about
a week. On taking five drops of a saturated solution of arsenic thrice a
day the paroxysms ceased, and returned no more, and at the same time his
appetite became much improved.

Thirdly. A gentleman about 65 years of age had for about ten years been
subject to an intermittent pulse, and to frequent palpitations of his
heart. Lately the palpitations seemed to observe irregular periods, but the
intermission of every third or fourth pulsation was almost perpetual. On
giving him four drops of a saturated solution of arsenic from a two-ounce
phial about every four hours for one day, not only the palpitation did not
return, but the intermission ceased entirely, and did not return so long as
he took the medicine, which was three or four days.

Now as when the stomach has its action much weakened by an over-dose of
digitalis, the pulse is liable to intermit, this evinces a direct sympathy
between these parts of the system, and as I have repeatedly observed, that
when the pulse begins to intermit in elderly people, that an eructation
from the stomach, voluntarily produced, will prevent the threatened stop of
the heart; I am induced to think, that the torpid state of the stomach, at
the instant of the production of air occasioned by its weak action, caused
the intermission of the pulse. And that arsenic in this case, as well as in
the cases of agues above mentioned, produced its effects by stimulating the
stomach into more powerful action; and that the equality of the motions of
the heart was thus restored by increasing the excitement of the sensorial
power of association. See Sect. XXV. 17. Class IV. 2. 1. 18.

10. Where arsenic has been given as a poison, it may be discovered in the
contents of the stomach by the smell like garlic, when a few grains of it
are thrown on a red-hot iron. 2. If a few grains are placed between two
plates of copper, and subjected to a red heat, the copper becomes whitened.
3. Dissolve arsenic in water along with vegetable alcali, add to this a
solution of blue vitriol in water, and the mixture becomes of a fine green,
which gradually precipitates, as discovered by Bergman. 4. Where the
quantity is sufficient, some wh