A'ERONAUT'ICS ( Gk. air + ratIr7/c, I/CWS, sailor). The art of aerial navigation. It is of comparatively recent development, as the ancients seem to have been convinced that the navigation of the air war impossible to human beings, and to have made no attempt to accomplish it. Grecian mythology, however, furnishes us the fable of Daedalus, who made wings of feathers cemented with wax for himself and his son Icarus, and endeavored to escape by flight from King Minos. The story of how Icarus, by forgetting the injunctions of his father and soaring so high that the melted the wax of his wings, was precipitated into tile sea, while Daedalus accomplished his flight in safety, is familiar to all as a fanciful legend of ancient mythology. A more comprehensible tale, but yet one Which is based entirely on tradition, is that told of the wooden clove invented by the Greek mathematician Archytas. According to the tradition, this dove could maintain sus tained flight and was set in motion by ''hidden and inclosed air." Passing to the Middle Ages, we find the field scarcely more fruitful in facts relating to aerial navigation. There are record ed a few actual and usually disastrous attempts at gliding flight, which will he noted further on, but generally speaking the consideration of the problem of flight by human beings was confined mostly to surmise and speculations which in many cases were nearly as fanciful as the earlier Grecian fables. The statement of these meagre facts brings us to the invention which fur the first time placed the art of aerial navigation upon a more practical basis than mere specula tion. namely, the discovery of the balloon.
BALLOoNs. The genii of the invention of bal loons is to he found in the discovery by the Eng lish chemist and physicist, henry Cavendish, in I766, of the remarkable lightness of hydrogen gas, then called inflammable air. Professor Black, of seems to have been the first who conceived the idea that a light envelope con taining this gas would rise of itself. lle request ed Dr. Morro, the professor of anatomy, to give him some thin animal membrane for the experi ment; but for some reason or other the experi ment was never made. The first practical at tempts were made by Cavallo. who in 1772 filled
swine's bladders and paper bags with the gas, but found the former too heavy and the latter too porous, and only succeeded in raising soap-bubbles inflated with the gas. The inven tion of the balloon is due to the two brothers Etienne and Joseph Montgolfier, paper-makers at Annonay, in France, whose names are as dis tinguished in the development of their own industry as in the history of aeronautics. It occurred to these brothers, on reading Caven dish's Different Kinds of Air, that the air could be rendered navigable by inclo,ing a light gas within a covering of inconsiderable weight. Led by their vocation, they fixed upon paper as the most fitting material for the purpose. and first attempted to make balloons of paper filled with inflammable air. Finding that these emptied themselves almost as soon as they were filled, instead of abandoning the paper an unsuit able covering for the gas, they sought after an other gas more suited to the paper. They thought that the gas which resulted from the combus tion of slightly moistened straw and wool would answer the purpose, since it had, as they imag ined, an upward tendency, not only from its being heated, but from its electrical properties, which caused it to be repelled from the ground. It is hardly necessary to say that this so-called Montgolfier gas possessed no advantages for raising balloons other than that possessed by heated air of any .kind; in fact. the abundant smoke with which it was mixed, by adding to its weight, rather detracted from its merits. At .Avignon, in November, 1782, Etienne .Nlontgol fier first succeeded in causing a silk parallelopi ped, of about 50 feet, to rise to the ceiling of a room. Encouraged by this success, the brothers made experitnents on a larger scale at Annonay with an equally happy result; and finally. in .lone, 1783. in the presence of the assembly of the estates Of Vivarais and of an fin mense multitude, they raised a balloon 35 feet in diameter to a height of 1500 feet. This balloon, nearly spherical in shape, •aS made of packcloth, covered with paper, and was heated by a small iron grate placed beneath it, in which ten pounds of moist straw and wool were burned.