despaired; after a dream, wherein an old man came and talked with him about the "Mercury of the Sages," the Alchemist thought he would charm the Mercury, and so he used a form of incantation. The Mercury suddenly began to speak, and asked the Alchemist why he had troubled him so much, and so on. The Alchemist replied, and questioned the Mercury. The Mercury makes fun of the philosopher. Then the Alchemist again torments the Mercury by heating him with all manner of horrible things. At last Mercury calls in the aid of Nature, who soundly rates the philosopher, tells him he is grossly ignorant, and ends by saying: "The best thing you can do is to give yourself up to the king's officers, who will quickly put an end to you and your philosophy." As long as men were fully persuaded that they knew the plan whereon the world was framed, that it was possible for them to follow exactly "the road which was followed by the Great Architect of the Universe in the creation of the world," a real knowledge of natural events was impossible; for every attempt to penetrate nature's secrets presupposed a knowledge of the essential characteristics of that which was to be investigated. But genuine knowledge begins when the investigator admits that he must learn of nature, not nature of him. It might be truly said of one who held the alchemical conception of nature that "his foible was omniscience"; and omniscience negatives the attainment of knowledge. The alchemical notion of a natural state as proper to each substance was vigorously combated by the Honourable Robert Boyle (born 1626, died 1691), a man of singularly clear and penetrative intellect. In _A Paradox of the Natural and Supernatural States of Bodies, Especially of the Air_, Boyle says:--"I know that not only in living, but even in inanimate, bodies, of which alone I here discourse, men have universally admitted the famous distinction between the natural and preternatural, or violent state of bodies, and do daily, without the least scruple, found upon it hypotheses and ratiocinations, as if it were most certain that what they call nature had purposely formed bodies in such a determinate state, and were always watchful that they should not by any external violence be put out of it. But notwithstanding so general a consent of men in this point, I confess, I cannot yet be satisfied about it in the sense wherein it is wont to be taken. It is not, that I believe, that there is no sense in which, or in the account upon which, a body may he said to be in its natural state; but that I think the common distinction of a natural and violent state of bodies has not been clearly explained and considerately settled, and both is not well grounded, and is oftentimes ill applied. For when I consider that whatever state a body be put into, or kept in, it obtains or retains that state, assenting to the catholic laws of nature, I cannot think it fit to deny that in