The answer to this question lies in the fact that there is no principle more thoroughly established than that no combination of machinery can create energy. So far as our present knowledge of nature goes we might as well try to create matter as to create energy, and the creation of energy is essential to the successful working of a perpetual-motion machine because some power must always be lost through friction and other resistances and must be supplied from some source if the machine is to keep on moving. And since the law of the conservation of energy makes it positive that no more power can be given out by a machine than was originally supplied to it, it seems as certain as anything can be that the construction of a perpetual-motion machine is one of the impossibilities. V TRANSMUTATION OF THE METALS The "accursed thirst for gold" has existed from the earliest ages and, as the apostle says, "is the root of all evil." Those who have a greed for power, a craving for luxury, or a fever for lust, all think that their wildest dreams might be realized if they could only command sufficient gold. Never was there a more lurid picture of a mind inflamed with all these evil passions than that set forth by Ben Jonson in the Second Act of "The Alchemist," and who can doubt but that such desires and dreams spurred on many, either to engage in an actual search for the philosopher's stone, or to become the dupes of what Van Helmont calls "a diabolical crew of gold and silver sucking flies and leeches." As we might naturally expect, the early history of alchemy is shrouded in myths and fables. Zosimos the Panopolite tells us that the art of Alchemy was first taught to mankind by demons, who fell in love with the daughters of men, and, as a reward for their favors, taught them all the works and mysteries of nature. On this Boerhaave remarks: "This ancient fiction took its rise from a mistaken interpretation of the words of Moses, 'That the sons of God saw the daughters of men that they were fair, and they took them wives of all which they chose.'[2] From whence it was inferred that the sons of God were daemons, consisting of a soul, and a visible but impalpable body, like the image in a looking-glass (to which notion we find several allusions in the evangelists); that they know all things, appeared to men and conversed with them, fell in love with women, had intrigues with them and revealed secrets. From the same fable probably arose that of the Sibyl, who is said to have obtained of Apollo the gift of prophecy, and revealing the will of heaven in return for a like favor. So prone is the roving mind of man to figments, which it can at first idly amuse itself with, and at length fall down and worship." This idea of the supernatural origin of the arts permeates the ancient mythology which everywhere teaches that men were taught the sacred arts of medicine and chemistry by gods and demigods.