administered or used by any rational physician.14
That powdered hematite (red oxide of iron) possesses an astringent
quality and may really be looked upon as a medicine, he fully
recognizes, more particularly its efficacy for the cure of diseases of
the eye, but neither these nor similar qualities can be credited to
sapphires, emeralds, or jacinths. At the same time he is not disposed
to deny that these stones may have some subtle effect upon the body
when worn, or when held in the mouth for a time. Thus he agrees with
Avicenna (Ben Sina) that a jacinth worn over the heart may strengthen
that organ, for he knows of the power inherent in jasper to check a
hemorrhage. In a word his argument is principally directed against the
internal use of powders made from these hard and unassimilable stones.15
Robert
Boyle, writing in 1663, attempts to show that the theory of the
therapeutic action of precious stones is not incompatible with observed
facts. In this connection he says :16
I
am not altogether of their mind, that absolutely reject the internal
use of Leaf-Gold, Rubies, Saphyrs, Emeralds, and other Gems, as things
that are unconquerable by the heat of the stomach. For as there are
rich Patients that may, without much inconvenience, goe to the price of
the dearest Medicines ; so I think the Stomach acts not on Medicines
barely upon the account of ite heat, but is endowed with a subtle
dissolvent (whence never it hath it) by which it may perform divers
things not to be done by so languid a heat. And I have, with Liquors of
differing sorts, easily drawn from Vegetable Substances, and perhaps
unrectified, sometimes dissolved, and sometimes drawn Tinctures from
Gems, and that in the cold . . . But that which I chiefly consider on
this occasion is, that 'tis one thing to make it probable, that is, possible, Gold, Rubies, Saphyrs, etc., may be wrought upon by humane Stomach; and another thing to shew both that they are wont to be so, and that they are actually endowed with those particular
"Op. cit., p. 116. * Op. cit., pp. 118-122.
"Boyle, "On the Usefulness of Experimental Philosophy," Oxford, 1664, p. 108.
