An adequate notion of his schemes in mechanical science may be gathered from one of his own letters—Epistola Fratris Rogerii Baconis de Secretis Operibus Artis et Naturæ et de nullitate Magiæ, Hambourg, 1618. Having undertaken to demonstrate that by the help of natural science it is possible to actually perform the pretended prodigies of magic, he further assures us that machines may be constructed for navigation without the aid of rowers, in such a manner that vessels will be borne through the water with extraordinary velocity, under the direction of a single man. “It is equally possible to construct cars which may be set in motion with marvellous rapidity, independently of horses or other animals. Flying machines may also be made, the man seated in the centre, and by means of certain contrivances beating the air with artificial wings.” In the same way Bacon anticipated the invention of the crane, diving apparatus, suspension bridges, &c. These things, he declares, were known to the ancients, and may still be recovered.
“Should we be surprised,” demands one of his biographers, “if all these prodigies obtained for him the name of magician in an age of superstition and ignorance? the friars of his own order refused to let his works into their library, as if he were a man who ought to be proscribed by society. His persecution increased till, in 1278, he was imprisoned and forced to confess his repentance of his pains in the arts and sciences. He was constrained to abandon the house of his order, and to form a retreat where he might work in quiet.”
The reputation of Bacon as a magician spread over Western Europe. He was supposed to be indebted for his wisdom to incessant communication with demons. Wierus accuses him of goëtic magic, and erudite persons affirm that Antichrist will make use of his enchanted mirrors for the performance of lying miracles. He really believed in judicial astrology and in the philosophical stone. “By neglecting the lights of experience,” he says, “alchemy can seldom produce gold of twenty-four carats. Few persons have carried the science to so high a point. But with the help of Aristotle’s ‘Secret of Secrets,’ experimental science has manufactured not only gold of twenty-four degrees, but of thirty, forty, and onward according to pleasure.”
The application of alchemy to the extension of life was another subject of study with Roger Bacon. The grand secret, he assures us, does not only ensure the welfare of the commonwealth and of the individual, but it may be used to prolong life, for that operation by which the most inferior metals is purged from the corrupt elements which they contain till they are exalted into the purest gold and silver, is considered by every adept to be eminently calculated to eliminate so completely the corrupt particles of the human body, that the life of mortality may be extended to several centuries.
A citation by Franciscus Picus from Bacon’s “Book of the Six Sciences” recounts how a man may become a prophet and predict the future by means of a mirror which Bacon calls Almuchefi, composed in accordance with the laws of perspective under the influence of a benign constellation, and after the body of the individual has been modified by alchemy.
On the word of a man who enjoyed his full confidence, he tells us how a celebrated Parisian savant, after cutting a serpent into fragments, taking care to preserve intact the skin of its belly, subsequently let loose the animal, which began immediately to roll upon certain herbs, and their virtues speedily healed him. The experimenter examined these herbs, and found them of a remarkably green colour. On the authority of Artephius, he relates how a certain magician, named Tantalus, and who was attached to the person of the King of India, had discovered by his proficiency in planetary lore, a method of preserving life over several centuries. He enlarges on the potency of theriac in the excessive prolongation of life. He lauds the flesh of winged serpents as a specific against senility in mankind. By the hygiene of Artephius he informs us that that adept lived over a thousand years. If Plato and Aristotle failed to prolong their existence it is not surprising, for they were ignorant even of the quadrature of the circle, which Bacon declares to have been well known at his time, and which is indefinitely inferior to the grand medical doctrine of Artephius.[I]
The chemical investigations of the great English Franciscan have proved valuable to the science which he loved. He studied carefully the properties of saltpetre, and if he did not discover gunpowder, he contributed to its perfection by teaching the purification of saltpetre by its dissolution in water and by crystallisation. He also called attention to the chemical rôle played by the air in combustion.[J]
Many of Bacon’s works still remain in manuscript, but his Speculum Alchimiæ was done into French by Girard de Tourmes, and published at Lyons in duodecimo and octavo in 1557. De Potestate Mirabili Artis et Naturæ, which is merely a chapter of the Epistle already cited, was translated by the same hand.
In another work, entitled Radix Mundi, the supreme secret of Hermetic philosophy is said to be hidden in the four elements. This treatise, which quotes Paracelsus, is, however, an impudent forgery.
The “Mirror of Alchemy,” like other works of the philosophers, appeals to Hermes as to a master-initiate, whose authority is not only sufficient but final. The natural principles of all metals are argent vive, that is, sophic mercury, and sulphur. The various proportions in which these principles are combined, together with their degrees of purity, constitute the sole difference between the best and the basest metal.