Parseval Kite Balloon.
Another valiant English leader in aërostation was James Glaisher, member of the British Association for the Advancement of Science. As one of a committee of twelve appointed by that body in 1861, to explore the higher strata of the atmosphere by means of the balloon, he volunteered his services as an observer, when no other capable man could offer to do so. With a professional aëronaut, Mr. Coxwell, and a new balloon specially constructed for the work, cubing 90,000 feet, he made eleven ascensions for the society, four from Wolverhampton, seven from Woolwich. Incidentally he made seventeen other ascents of various altitude; not at the expense of the committee, but as a scientific passenger in public balloon ascents advertised beforehand.
One of the earliest authenticated devices of this kind was the invention of Blanchard, described by him in the Journal de Paris, August 28, 1781, nearly two years before the invention of the hot-air balloon, of which he became later an enthusiastic votary. As his device is but one of a large number that appeared before the close of the nineteenth century, and the advent of light motors, the reader who wishes fuller acquaintance with man-driven airships may be referred to Mr. Chanute’s book, entitled Progress in Flying-Machines, which describes a large variety of such inventions, and discusses the merit and weakness of each.
The ascent of this, the first hydrogen balloon, was a popular and a memorable event. The field was lined with troops. The curious spectators had thronged every thoroughfare and darkened every housetop. It was an all day festival, inaugurating a peculiarly French science, with French animation. The booming of cannon announced to all Paris the impending flight of the balloon. At five o’clock, in the presence of 50,000 spectators, and in a shower of rain, the balloon rose more than half a mile and entered the clouds. The people overwhelmed with surprise and enthusiasm, stood gazing upward, despite the rain, observing every maneuver till the vessel had ascended and faded from view.
The public inauguration of aëronautics occurred on June 5, 1783, at Annonay, the home of the Montgolfier family, 36 miles from Lyons. The states of Vivarais being assembled at that place, were invited to witness the ascension. The Deputies and many spectators found in the public square an enormous bag which, with its frame, weighed 300 pounds, and would inflate to a ball 35 feet in diameter. When told that this huge mass would rise to the clouds they were astonished and incredulous. The Montgolfiers, however, lit a fire beneath and let the bag speak for itself. It gradually distended, assuming a beautiful form, and struggling to free itself from the men who were holding it. At a given signal it was released; it ascended rapidly, and in ten minutes attained a height of 6,000 feet. It drifted a mile and a half and sank gently to the ground.
Stephen Montgolfier now wishing to send up human passengers, made a balloon of 100,000 cubic feet capacity. It was shaped like a full lemon pointing upward, with a cylindrical neck below, 16 feet in diameter. Around this neck was a wicker balcony three feet wide, to carry the aëronauts, bundles of straw for fuel, pails of water and sponges to extinguish incipient conflagrations, here and there in the balloon, during a journey. Through stokeholes in the side of the neck sheaves of straw could be forked to the grate suspended centrally below by radial chains. During inflation the base of the balloon rested on a platform, and its top was supported by a rope stretched between two poles. The vessel when completed, in a garden of the Faubourg St. Antoine, was 85 feet high by 48 feet across, and weighed 1,600 pounds. About its zone, painted in oil, were elegant decorations; portraits, cyphers of the king’s name, fleur-de-lis, with fancy borders below and above; while higher still, on the arching dome of the bag, were all the signs of the celestial zodiac.
he vessel selected for that famous cruise was The Great Balloon of Nassau, then recently built by Mr. Green and representing all that his skill and experience could devise. It was of pear shape, formed of the finest crimson and white silk, “spun, wove and dyed expressly for the purpose,” and comprising when distended a volume of 85,000 cubic feet. From its stout balloon-ring six feet in diameter was suspended a wicker car measuring nine feet long by four wide, having a seat across either end, and a cushioned bottom to serve as a bed, if such should be needed. Across the middle of the car was a plank supporting a windlass for raising or lowering the guide-rope, that is a heavy rope which could be trailed over land, or water, to keep the balloon at a nearly constant level without expenditure of ballast, and to check its speed on landing. This valuable device invented by Mr. Green in 1820, was now to receive adequate trial, which, indeed, formed one of the chief purposes of the cruise. Other paraphernalia of the voyage were food and drink, warm clothing, lamps, trumpets, telescopes, barometers, a quicklime coffee-heater, a grapnel and cable, and a ton of sand ballast in bags.
A still more elaborate and colossal air ship was the Geant, constructed in 1863, for A. Nadar of Paris. It was made of a double layer of white silk, had a volume of 215,000 cubic feet and a buoyancy of 4½ tons. The car was a wicker cabin 13 feet wide by 7 feet high, with a wicker balcony round the top so that the roof could be used as an observation deck—a delightful place to loll in the starlight, or watch the morning sun “flatter the mountain tops with sovereign eye.” The closed car comprised two main rooms with a hallway between them, one containing the captain’s bed and baggage, the other having three superposed berths for passengers. Minor divisions of the car were reserved for provisions, a lavatory, photography and a printing press, the latter to be used for the dissemination of news from the sky, as the navigators floated from state to state. A compensator balloon of 3,500 cubic feet, just below the main bag and connected with it, received the escaping gas during expansion with increase of tempera61ture or altitude, and gave it back on contraction.
The ripping panel, invented in 1844 by America’s foremost pioneer aëronaut, John Wise, is a simple and an excellent practical device. This is a long patch running longitudinally above the equator of the balloon, feebly sewed to the envelope, and having a cord, called the “ripping cord,” extending down to the car along the outside or inside of the bag, so that the pilot on coming to earth can let out the gas quickly by tearing a rent in the balloon, thus flattening it promptly on the earth’s surface, so as to avoid dragging and bumping if any wind prevails.
The first attempts at balloon propulsion could not be seriously regarded by trained engineers, even at the inception of aëronautics; but still, as infantile steps in the new art, they may deserve passing notice.
Blanchard, on March 2, 1784, made the first real effort to steer a balloon, using for that purpose a spherical gas bag and car provided with aërial oars and a rudder. As he was about to ascend, however, from the Champs de Mars, a young officer with drawn sword persisted in accompanying the pilot, thus compelling Blanchard to leave his wings on earth to allow sufficient buoyancy for himself and his obtrusive guest. His first trial was, therefore, frustrated; but subsequent ones made with that inadequate contrivance also proved futile under the best circumstances; for the scheme was evidently puerile, though tried by various grown-up men besides M. Blanchard.
A more reasonable plan for practical navigation was devised and tried by the Robert brothers. A melon-shaped balloon, fifty-two feet long by thirty-two feet in diameter, was made of silk and inflated with pure hydrogen. Beneath was suspended a longish car of light wood covered with sky-blue silk. This elegant ship was to be rowed through heaven by means of six silken oars actuated by sturdy sailors. A silken rudder should guide her at pleasure when the winds were asleep, or softly playing in the placid sky. She was a fairy bark, indeed, a soaring castle lovely to behold.
After a preliminary trial, accompanied by their patron, the Duke de Chartres, they were ready for a substantial journey. On September 19, 1784, the vessel was inflated and taken to the Garden of the Tuileries, in front of the palace, where its cords were held by Marshall Richelieu and three other noblemen. At eleven forty-five the two Roberts and their brother-in-law arose and drifted beyond the horizon on a seven hours’ cruise. Before coming to earth, they plied the oars vigorously, and described a curve of one kilometer radius, thus deviating 22° from the feeble wind then prevailing.
A.A. Ballast bags filled with sand
B. Instruments (such as a statoscope, which shows at any moment whether the balloon is rising or falling; and an altitude meter)
C. Ring by which car is attached to balloon.
But as airships were built larger, and greater speeds were obtained, it became necessary to strengthen the envelopes with some form of keel; and this led to a type which is known as the semi-rigid, and is developed successfully in France. The figure illustrates an airship of this build. Along the lower side of its envelope is placed a light, rigid framework or keel, and from this is suspended the car which contains engines and crew.
A. Gas-containing envelope
B. Strengthening keel
E. Car carrying engines, propeller, and crew.
Hull of a Zeppelin during construction.
Craft of the semi-rigid type provide a link between small, non-rigid ships and the very large machine which is built with an entirely rigid framework, and has its example in the Zeppelin. The maker forms a skeleton hull of aluminium or some light metal alloy, a method that is shown in figure. The hull of a Zeppelin, slightly more than 500 feet in length, is sheathed with tightly stretched fabric; and within it are the gas-containers—a row of seventeen separate balloons, each in a compartment by itself, and containing a total of nearly 1,000,000 cubic feet of gas—which give these airships a lifting power of close upon 30 tons.
A typical craft, representing the first of those navigated with any certainty, is shown in Figure. A gas-containing envelope, made of a light, strong, varnished fabric, is kept taut by the pressure of the gas within; the car, constructed of wood or metal tubing, is suspended by ropes from the envelope, and contains engine and crew, with a two-bladed propeller revolving astern. Such a machine, in its control, had an elevating-plane and rudder, upon the same principle as those of the aeroplane. One of the difficulties to be overcome was the expansion and contraction of gas in the envelope owing to differences in altitude and temperature. When the craft ascended, its envelope completely inflated, the gas began to dilate owing to the outer air becoming less dense; and some had to be allowed to escape through automatic valves. Then, should the machine descend to a lower level, there was not sufficient gas in the envelope to keep it tightly stretched, and it tended to sag at the bow as it was driven through the air.
A. Gas envelope
B. Car suspended below envelope
C. Motor, which drives propeller (D) through a shaft
E. Small horizontal plane for rising or descending
F. Fixed fin, or keel plane, to give stability
A. Wheels operating elevating-planes and rudder
B. Height recorder
C. Speaking-tube to communicate with engineers.
Coal-gas superseded hot air in the filling of balloons, the latter being unsatisfactory, seeing that it cooled rapidly and allowed the balloon to descend; the only alternative being to do what some of the first aeronauts did, and burn a fire below the neck of their balloon even when in the air. But the dangers of this were great, seeing that the whole envelope might easily become ignited. With balloons filled with coal-gas long flights were possible, but they had always this disadvantage—the voyagers were at the mercy of the wind, and could not fly in any direction they might choose. If the wind blew from the north then they were driven south, the balloon being a bubble in the air, wafted by every gust. Aeronauts became disgusted with this inability to guide the flight of a balloon, and many quaint controls were tested; such, for example, as the use of a large pair of oars with which the balloonist, sitting in the car of his craft, rowed vigorously in the air.
...it was followed in due course by the use of small steam engines and electric motors, which were made to turn propellers such as are used in aeroplanes. For such experimental craft, the rounded form of gas-container was abandoned and a cigar-shaped envelope adopted, pointed at both ends, which could be more easily driven through the air. An airship of a crude and early type is seen here. It was built by an experimenter named Gifford, and in 1852 it flew at the rate of seven miles an hour.
A. Gas-containing envelope; B. Car suspended below envelope, which carried the aeronaut and a 3-horse-power steam engine; C. Two-bladed propeller driven by the engine; D. Rudder (in the form of a sail) by which the machine could be steered from side to side.
An Airship leaving its shed
A. The machine emerging stern first
B. A sister craft in dock
C. The launching crews
D. Rails upon which the cars of the airship move, so as to prevent its swinging sideways in a gust
E. Outlook station upon the roof of the shed
F. Workshops; living quarters for the crews; plant for making hydrogen gas.
Airships, like aeroplanes, are being armed with guns and bombs; and their power of raising weights enables them to carry heavy weapons. Large and highly destructive bombs have been tested in the German airships, being released over the sea and aimed at targets in the form of rafts. Latest-type airships also carry guns in their cars; and the Zeppelins have a platform upon the tops of their hulls, reached by a ladder through the middle of the ship, from which a machine-gun can be fired upward. This is a very necessary precaution, and is intended to frustrate the attack of an aeroplane. It would be the aim of the latter, whenever possible, to manœuvre above its big enemy—as suggested in figure —and drop a bomb upon its hull. Hence the construction of the top platform of the airship, from which her gunners can direct a vigorous fire aloft.
It was on June 5, 1783 that Stephen and Joseph Montgolfier, two French brothers, sent up the first balloon. You can just imagine the amazement it caused when it arose from the ground.