186 AERONAUTICS [EARLY EXPERIMENTS. ments was believed to deal in magic, and to perform his feats of skill chiefly through the secret aid granted him by the prince of darkness; and in a later and comparatively recent period, those wretched creatures whom the unfeeling credulity of our ancestors, particularly during the prevalence of religious fanaticism, stigmatised and murdered under the denomination of witches, were supposed to work all their enchantments, to change their shapes at will, and to transport themselves through the air with the swiftness of thought, by a power derived from their infernal master, to whom was thus assigned the privilege of conferring- the gift of aerial navigation upon his servants. During the darkness of the Middle Ages every one at all distinguished for his knowledge in physics was gene rally reputed to have obtained the power of flying in the air. Friar Bacon did not scruple to claim the invention; and the credulity and indulgent admiration of some authors have lent to these pretensions more credit than they really deserved. Any one who takes the trouble to examine the passages of Bacon s obscure and ponderous works will find that the propositions advanced by him are seldom founded on reality, but ought rather to be considered as the illu sions of a lively fancy. Albertus Magnus, who flourished in the first half of the 13th century, was reputed to have discovered the art; and to give an idea of the state of the physical sciences at that time, it is worth while to quote the following recipes from his De Mirabilibus Naturae: " Take one pound of sulphur, two pounds of willow-carbon, six pounds of rock-salt ground very fine in a marble mortar; place, when you please, in a covering made of flying papy rus to produce thunder. The covering, in order to ascend and float away, should be long, graceful, well filled with this fine powder; but to produce thunder, the covering should be short, thick, and half full." (Quoted in Astra Castro,, p. 25.) Regiomontanus, the first real mathema tician after the partial revival of learning, is said, like Archytas, to have formed an artificial dove, which flew before the Emperor Charles V. at his public entry into Nuremberg; but the date of Regiomontanus death shows this to have been impossible. ttempis Attempts at flying have, as a rule, been made by a some- flying- what low class of projectors, who have generally united some little share of ingenuity to a smattering of mechanics. At the beginning of the 16th century an Italian alchemist visited Scotland, and was collated by James IV. to the abbacy of Tungland, in Galloway. Having constructed a set of wings, composed of various plumage, he undertook from the walls of Stirling Castle to fly through the air to France. This feat he actually attempted, but he soon came to the ground, and broke his thigh-bone by the violence of the fall an accident he explained by asserting that the feathers of some fowls were employed in his wings, and that these had an affinity for the dunghill, whereas, if composed solely of eagles feathers, they would have been attracted to the air. This anecdote has furnished to Dunbar, the Scottish poet, the subject of one of his rude satires. In 1617, Fleyder, rector of the grammar school at Tiibingen, delivered a lecture on flying, which he published eleven years afterwards. A poor monk, however, ambitious to reduce the theory to practice, provided himself with wings; but his machinery broke down, and falling to the ground, he broke his legs and perished. Bishop Wilkins (Mathematical Magick, 1648) says it was related that "a certain English monk called Elmerus, about the Confessor s time," flew by means of wings from a tower a distance of more than a furlong; that another person flew from St Mark s steeple at Venice; and another, at Nuremberg. He also quotes Busbequius to the effect that a Turk also attempted something of the kind at Constantinople. It would probably not be very difficult to make a long list of such narrations, in some of which the experimenter is related to have been successful, and in others to have failed; but the evidence is in no case very good, and we may feel certain that all the traditions of attempts with a successful issue are false. In Borelli s posthumous work, De Motu Animalium, pub- Borulli lished at Rome in 1680-81, he calculated the enormous shows tl strength of the pectoral muscles in birds; and his proposition im l )0ss i- cciv. (vol. i. pp. 322-326) is entitled " Est impossible, ut ^ y a ?.{ homines propriis viribus artificiose volare possint," in which by the a he clearly points out the impossibility of man being able by of iny-s his muscular strength to give motion to wings of sufficient extent to keep him suspended in the air. But Borelli did not, of course, as has sometimes been stated, demonstrate the impossibility of man s flying otherwise than merely by means of his own muscular power. A very slight consideration of the matter shows that, Sailing i although the muscles of man may not be of sufficient tlie air - strength to enable him to use wings, this objection does not apply against the possibility of making a flying chariot in which the motive power should be produced mechanically as in a watch, or a boat to float in the atmosphere. Both these projects have therefore always engaged the attention of abler men than has the art of flying, and it was only the ignorance of the nature and force of the atmosphere, as well as of the properties of all aeriform bodies, that caused so long a time to elapse before the invention of the balloon. Albert of Saxony, a monk of the order of St Augustine, Albert c and a commentator on the physical works of Aristotle, Saxony, seems first to have comprehended (though in a very vague and erroneous manner) the principles on which a body might be made to float in the atmosphere. Adopting, of course, Aristotelian views with regard to the nature of the elements, he considered that, as fire is more attenuated, and floats above our atmosphere, therefore a small portion of this ethereal substance, enclosed in a light hollow globe, would raise it to a certain height and keep it suspended in the air; and that, if more air were introduced, the globe would sink like a ship when water enters by a leak. Long afterwards Francis Mendoza, a Portuguese Jesuit, Francis who died in 1626, at the age of forty-six, embraced this Memloz; theory, and he held that the combustible nature of fire was no real obstacle, as its extreme levity and the extension of the air would prevent it from supporting inflammation. Casper Schott, also a Jesuit, adopted the same specula- Caster tion, only that he replaced the fire by the thin ethereal Schott. substance which he believed floated above our atmosphere ; but, of course, the difficulty of procuring any of this ether was a sufficient obstacle. Similar notions have been revived at different times. They were likewise often blended with the alchemical tenets Alchemi so generally received in the course of the 15th, 16th, and notions. part of the 1 7th centuries. Thus Schott quotes Lauretus Lauretus Laurus to the effect that if swans eggs or leather balls be Lauvus. filled with nitre, sulphur, or quicksilver, and be exposed to the sun, they will ascend. It was also believed that dew was of celestial origin, being shed by the stars, and that it was drawn up again in the course of the day to heaven by the heat of the sun. Thus Laurus states that hens eggs filled with dew and exposed to the solar heat will rise. He was so grossly ignorant, however, of the principles of motion, that it is not worth while even to allude to his other assertions. Cyrano de Bergerac (born 1620) wrote a philosophical Romance romance entitled Histoire Comique des Estats et Empire de of t yfan la Lime, and Les Estats et Empire du Soleil (from which el ~ -* CfAfJl f* Swift is supposed to have derived the idea of writing portions of G ul liver s Travels). To equip himself for per forming the journey to the moon, the French traveller fastens round his body a multitude of very thin flasks
gerr.c.
