rare gem if he saw it. To which Helvetius replied, that he certainly should not. The burgher immediately drew from his pocket a small ivory box, containing three pieces of metal, of the colour of brimstone, and extremely heavy; and assured Helvetius, that of them he could make as much as twenty tons of gold. Helvetius informs us, that he examined them very attentively; and seeing that they were very brittle, he took the opportunity to scrape off a small portion with his thumb-nail. He then returned them to the stranger, with an entreaty that he would perform the process of transmutation before him. The stranger replied, that he was not allowed to do so, and went away. After his departure, Helvetius procured a crucible and a portion of lead, into which, when in a state of fusion, he threw the stolen grain from the philosopher’s stone. He was disappointed to find that the grain evaporated altogether, leaving the lead in its original state.
Some weeks afterwards, when he had almost forgotten the subject, he received another visit from the stranger. He again entreated him to explain the processes by which he pretended to transmute lead. The stranger at last consented, and informed him, that one grain was sufficient; but that it was necessary to envelope it in a ball of wax before throwing it on the molten metal; otherwise its extreme volatility would cause it to go off in vapour. They tried the experiment, and succeeded to their heart’s content. Helvetius repeated the experiment alone, and converted six ounces of lead into very pure gold.
The fame of this event spread all over the Hague, and all the notable persons of the town flocked to the study of Helvetius to convince themselves of the fact. Helvetius performed the experiment again, in the presence of the Prince of Orange, and several times afterwards, until he exhausted the whole of the powder he had