The arch-quack Paracelsus makes the assertion, of course; unblushing mendacity was part of his stock-in-trade; and he pretends even to define the methods by which it may be realized. Unfortunately, to ordinary mortals his description is absolutely unintelligible. Others there are who affirm that they had seen it, and seen it in operation, transmuting lead, quicksilver, and other of the inferior metals into ruddy gold. One wonders that they did not claim a share in a process which involved such boundless potentialities of wealth!
Helvetius, the physician, though no believer in the magical art, tells the following wild story in his 'Vitulus Aureus':
On December 26, 1666, a stranger called upon him, and, after discussing the supposed properties of the universal medicine, showed him a yellow powder, which he declared to be the _lapis_, and also five large plates of gold, which, he said, were the product of its action. Naturally enough, Helvetius begged for a few grains of this marvellous powder, or that the stranger would at least exhibit its potency in his presence. He refused, however, but promised that he would return in six weeks. He kept his promise, and then, after much entreaty, gave Helvetius a pinch of the powder--about as much as a rape-seed. The physician expressed his fear that so minute a quantity would not convert as much as four grains of lead; whereupon the stranger broke off one-half, and declared that the remainder was more than sufficient for the purpose. During their first conference, Helvetius had contrived to conceal a little of the powder beneath his thumb-nail. This he dropped into some molten lead, but it was nearly all exhaled in smoke, and the residue was simply of a vitreous character.
On mentioning this circumstance to his visitor, he explained that the powder should have been enclosed in wax before it was thrown into the molten lead, to prevent the fumes of the lead from affecting it. He added that he would come back next day, and show him how to make the projection; but as he failed to appear, Helvetius, in the presence of his wife and son, put six drachms of lead into a crucible, and as soon as the lead was melted, flung into it the atoms of powder given to him by his mysterious visitor, having first rolled them up in a little ball of wax. At the end of a quarter of an hour he found the lead transmuted (so he avers) into gold. Its colour at first was a deep green; but the mixture, when poured into a conical vessel, turned blood-red, and, after cooling, acquired the true tint of gold. A goldsmith who examined it pronounced it to be genuine. Helvetius requested Purelius, the keeper of the Dutch Mint, to test its value; and two drachms, after being exposed to aquafortis, were found to have increased a couple of scruples in weight--an increase doubtlessly owing to the silver, which still remained enveloped in the gold, despite the action of the aquafortis.