performed many cures by means of it, and taught it to his surgeon, who,
after the Duke's death, sold it to many distinguished persons, by whose
agency it soon ceased to be a secret. What was this wonderful substance
which so astonished kings, princes, dukes, knights, and doctors? Nothing
but powdered blue vitriol. But it was made to undergo several processes
that conferred on it extraordinary virtues. Twice or thrice it was to be
dissolved, filtered, and crystallized. The crystals were to be laid in
the sun during the months of June, July, and August, taking care to turn
them carefully that all should be exposed. Then they were to be
powdered, triturated, and again exposed to the sun, again reduced to a
very fine powder, and secured in a vessel, while hot, from the sunshine.
If there seem anything remarkable in the fact of such astonishing
properties being developed by this process, it must be from our
short-sightedness, for common salt and charcoal develop powers quite as
marvellous after a certain number of thumps, stirs, and shakes, from the
hands of modern workers of miracles. In fact the Unguentum Armarium and
Sympathetic Powder resemble some more recent prescriptions; the latter
consisting in an infinite dilution of the common dose in which remedies
are given, and the two former in an infinite dilution of the common
distance at which they are applied.

Whether philosophers, and more especially metaphysicians, have any
peculiar tendency to dabble in drugs and dose themselves with physic, is
a question which might suggest itself to the reader of their biographies.

When Bishop Berkeley visited the illustrious Malebranche at Paris, he
found him in his cell, cooking in a small pipkin a medicine for an
inflammation of the lungs, from which he was suffering; and the disease,
being unfortunately aggravated by the vehemence of their discussion, or
the contents of the pipkin, carried him off in the course of a few days.