The Testimony of Helvetius.
§ 63. John Frederick Helvetius (see plate 13), an eminent doctor of medicine, and physician to the Prince of Orange, published at the Hague in 1667 the following remarkable account of a transmutation he claimed to have effected. Certain points of resemblance between this account and that of van Helmont (e.g., in each case the Stone is described as a glassy substance of a pale yellow colour) are worth noticing: “On the 27 December, 1666, in the forenoon, there came to my house a certain man, who was a complete stranger to me, but of an honest, grave countenance, and an authoritative mien, clothed in a simple garb like that of a Memnonite. . . .
“After we had exchanged salutations, he asked me whether he might have some conversation with me. He wished to say something to me about the Pyrotechnic Art, as he had read one of my tracts (directed against the sympathetic Powder of Dr. Digby), in which I hinted a suspicion whether the Grand Arcanum of the Sages was not after all a gigantic hoax. He, therefore, took that opportunity of asking me whether I could not believe that such a grand mystery might exist in the nature of things, by means of which a physician could restore any patient whose vitals were not irreparably destroyed. I answered: ‘Such a Medicine would be a most desirable acquisition for any physician; nor can any man tell how many secrets there may be hidden in Nature; yet, though I have read much about the truth of this Art, it has never been my good fortune to meet with a real Master of the Alchemical Science.’ I also enquired whether he was a medical man. . . . In reply, he . . . described himself as a brassfounder. . . . After some further conversation, the Artist Elias (for it was he) thus addressed me: ‘Since you have read so much in the works of the Alchemists about this Stone, its substance, its colour, and its wonderful effects, may I be allowed the question, whether you have not yourself prepared it?’ On my answering his question in the negative, he took out of his bag a cunningly-worked ivory box, in which there were three large pieces of a substance resembling glass, or pale sulphur, and informed me that here was enough of the Tincture for the production of 20 tons of gold. When I had held the precious treasure in my hand for a quarter of an hour (during which time I listened to a recital of its wonderful curative properties), I was compelled to restore it to its owner, which I could not help doing with a certain degree of reluctance. After thanking him for his kindness in shewing it to me, I then asked how it was that his Stone did not display that ruby colour, which I had been taught to regard as characteristic of the Philosopher’s Stone. He replied that the colour made no difference, and that the substance was sufficiently mature for all practical purposes. My request that he would give me a piece of his Stone (though it were no larger than a coriander seed), he somewhat brusquely refused, adding, in a milder tone, that he could not give it me for all the wealth I possessed, and that not on account of its great preciousness, but for some other reason which it was not lawful for him to divulge; . . .