vitriol, and a large quantity of poison ready prepared, the principal ingredients of which the physicians were not able to distinguish. Many have affirmed that sugar of lead was the chief ingredient[134]; but the consequences of the poison did not seem to indicate the use of that metal. For some years past a harmless plant, which is only somewhat bitter and astringent, the ivy-leaved Toadflax (_Linaria Cymbalaria_), that grows on old walls, has been loaded with the opprobrium of producing this slow poison, while at the same time it has been celebrated by others on account of its medicinal properties; but it is perhaps not powerful enough to do either mischief or good; and it is probable that it has been added to poisons either through ignorance, or to conceal other ingredients; for the emperor Charles VI., who was king of the Two Sicilies at the time when Tophania was arrested, told his physician Garelli, who communicated the same in a letter[135] to the celebrated Hoffmann, in 1718 or 1719, that the poison of that Italian Circe was composed of an arsenical oxide, dissolved in _aqua cymbalariæ_, and which I suppose was rendered stronger and more difficult to be detected by a salt that may be readily guessed. It is dreadful to think that this secret poison is administered as a febrifuge by ignorant or unprincipled physicians, quacks, and old women. It drives off obstinate fevers, it is true; but it is equally certain that it hastens death: it is therefore a cure, which is far worse than the disease, and against which governments and physicians cannot exclaim too severely. It was remarked at Rome, by accident, that lemon juice and the acid of lemons are, in some measure, counter-poisons; and a physician named Paul Branchaletti, respecting whom I can find no information, wrote a book expressly on this antidote to these drops, according to the account of Keysler, who however adds, “Everything hitherto found out, supposes that one has taken the drops only for a short time, or that one has had an opportunity to be upon one’s guard when suspicious circumstances occurred, and to discover the threatened danger.”