ON THERAPEUTIC USES OF STONES 379
powders
composed of various precious stones. In the space of fourteen days they
are asserted to have given the pope forty thousand ducats' worth of
these stones, a single dose costing as much as three thousand ducats.
The most costly remedy of all was a diamond administered to him at
Marseilles. Unfortunately, this lavish expenditure was of no avail;
indeed, according to our modern science, the remedies might have
sufficed to end the pope's life, without the help of his disease.14
The
old fancy that the diamond grew dark in the presence of poison is
explained by the Italian physician Gonelli as caused by minute and
tenuous particles which emanated from the poison, impinged upon the
surface of the diamond, and, unable to penetrate its dense mass,
accumulated on the surface, thus producing a superficial discoloration.
The diamond, being a cold substance, may have condensed moisture from
the body, and the one suffering from the poison may have emitted
exudations. But this elaborate explanation of a phenomenon which never
existed except in the imagination of those who related it is
characteristic of Gonelli, who was always ready to elucidate in some
similar way any of the marvels recounted in regard to precious stones.15
The emerald was employed as an antidote for poisons and for poisoned wounds, as well as against demoniacal possession.16 If worn on the neck it was said to cure the
14 Raumer, " Historisches Taschenbuch," I Ser,, vol. vi, Leipzig, 1835, p. 370.
15 Josephi Gonelli, " Thesaurus philosophicus, seu de gemmis," Neapoli, 1702, pp. 76, 77.
16 Lapidario del Rey D. Alfonso X, Codice Original, Madrid, 1881, f. xv.
