Not because my thoughts have been unusually aspiring of late, nor yet that I have grown weary of the monotony of the earth's surface, and am anxious “to go up" (as Mr. Miller's votaries term it), but I have recently been ballooning a little; and if the reader will step on board by aeronautic car a brief while, I will tell you what I have ascertained concerning that curious machine for “skylarking” a la Francais yclept the balloon.
The word, you know, is French, and signifies a little ball, from the circumstance, probably that the earliest made were mere toys of paper or of soap-suds. The appellation, as applied to some modern machines, so-called, is entirely a misnomer, they being characterized by anything rather than minuteness.
A desire to navigate the great atmospheric ocean above and around us has ever been prevalent in our world; and the means wherewithal to do it have severely tasked the ingenuity of man from early times. Taking a clue from the feathered voyagers which glide through the liquid expanse with a motion so enviably fleet, easy, and graceful, the speculators on the subject have often racked their inventions for a proper construction of wings that should enable man, therewith equipped, to compete with the eagle in his own element, and distance the condor. But experience demonstrated that all attempts on the part of the unfeathered dwellers of earth to rise into the air above it, must inevitably fail, from the disproportion of their muscular power to the force necessary to move wings of magnitude sufficient to support their weight.
It was only in the latter half of the last century that chemistry detected the nature and differences of the specific gravities of aeriform fluids. In some experiments made by Mr. Cavendish, in 1766, hydrogen gas, which was discovered by him, was found to be sixteen times lighter than common air. This gas, therefore, if prevented from diffusing itself, will rise to a height at which the air is sixteen times more attenuated than at the surface of the earth. No sooner was this fact announced, than Dr. Black inferred that a thin receptacle filled with it would mount to the ceiling of a room. Through some imperfection, however, the experiment failed, and it was several years before an envelope was devised sufficiently light to succeed. In 1782, Cavallo experimented with the gas, but could raise nothing heavier than a soap-bubble.
With the respective specific gravities of hydrogen gas and common air for data, it is easy to ascertain of what size a balloon must be to carry a given weight into the atmosphere. A globe of air one foot in diameter, at the level of the sea, weighs about one twenty-fifth of a pound avoirdupois. An equal globe of hydrogen is about six times lighter; consequently five-sixths of its whole buoyant force will act in impelling upward, and a sphere filled with it will tend to rise by a force equal to five-sixths multiplied by one twenty-fifth, that is, by one thirtieth of a pound avoirdupois. The ascentional forces of different spheres, filled with the same material, will be, by a well-known law, as the cubes of their diameters. Thus a sphere, twelve feet in diameter, will rise with a force of fifty-seven pounds; and one of twenty-four feet diameter, with a force eight times greater, or four hundred and fifty-six pounds. This is irrespective of the weight of the envelope, which should therefore be of the lightest possible material that is sufficiently strong. The substance most generally used for this purpose is silk, varnished with India-rubber.
A sphere of this kind, one foot in diameter, weighs about one twentieth of a pound ; one of twelve feet diameter, about seven pounds ; one of twenty-four feet, twenty-eight pounds; so that the actual weight, which a globe of twenty-four feet diameter, will carry up will be four hundred and fifty-six minus twenty-eight, or four hundred and twenty-eight pounds. At this rate, a balloon of sixty feet diameter will raise about seven thousand pounds and one of one and a half feet will barely float—the weight of the envelope being just equal to that of the imprisoned gas.
As the buoyant force is proportioned to the density of the air, it is evident that a balloon can rise only to such an elevation as will render the density equal to the machine and its appendages. The elevation will be retrenched by the fact that the expansive force of the gas constantly increases with the distance upward, and will ultimately overcome the resistance of any material of which a balloon can be made. An envelope quite filled at the surface of the earth, would be torn to shreds at a few miles above it, unless a portion of the gas were allowed to escape. For this purpose, the balloon furnished with a safety-valve, capable of being opened and shut at pleasure.
Although balloons are commonly filled with hydrogen, it is evident that any other substance specifically lighter than air would answer the purpose. In fact, the first balloons raised into the air were with rarefied air. As this rarefaction was produced by a fire kindled under them, they became filled smoke, and were called smoke-balloons. The ascensional force obtained by this means is not great, is attended with the inconvenience of carrying and the danger of the presence of fire.
The honor of sending up the first balloon is claimed for two brothers in Annonay, France, named Stephen and Joseph Montgolfier, in June, 1783. The material used in its construction was linen cloth, and the distension was produced by bundles of chopped straw. From the fact of this occasioning a great smoke, it would seem that the print of ascension was attributed to the smoke rather to the rarefaction of the air. On being let slip; ascended rapidly; reached an elevation of about a mile; remained suspended about ten minutes, fell at the distance of one and a half miles from starting-place.
When the news reached Paris, created general surprise and the virtuosi immediately began to consider the means of repeating the experiment. It was determined to employ hydrogen, Monsieur Charles, a celebrated lecturer on natural philosophy, undertook the supervision of the project. On the 26th August, 1783, the preparations completed, the balloon was transported with ceremony to the Champ de Mars. Intense interest was excited everywhere, and all Paris and its suburbs came forth to witness the novel phenomenon. The nest day, at five oclock PM, the discharge of cannon announced to the multitide that the critical moment had arrived.
A writer, who was among the spectators, thus describes the scene: " The globe, liberated from its stays, shot upward, to the great surprise of the lookers on, with such rapidity that in two minutes it had reached a height of three thousand feet. It traversed successively several clouds, by which it was repeatedly obscured. The violent rain which began to fall at the moment of ascent, did not retard its rapid progress, and the experiment was attended with complete success. The satisfaction was so great that even elegantly dressed ladies remained with their eyes intently fixed on the balloon, regardless of the rain which fell on them in torrents." After remaining in the air three-fourth of an hour, it fell at the distance of fifteen miles; when it was discovered that a rent had been made in its upper part, through which the gas had escaped."
No one had yet voyaged in these aerial carriages; but that feat shortly transpired. The honor of accomplishing it belongs to a young naturalist, named Pilatre de Rosier, and the Marquis d'Arlandes, who, on the twenty-first November, 1783, took their seat in the basket of a smoke-balloon, and after ascending more than three thousand feet, returned safely to the earth. The second experiment of the same kind was made by MM. in a hydrogen balloon, on the first January, 1784. After a flight of an hour and a half, they landed twenty-five miles from Paris, without accident. The balloon still retaining considerable buoyant force, M. Charles made another ascent alone. He rose to a height of two miles, and had the satisfaction of seeing the sun, which had set when he left the earth, again rise above the horizon. After remaining about thirty-five minutes, he descended about nine miles from where he had risen.
These successes encouraged other attempts, and no accident occurred until June 16th, 1786. On that
day the accomplished Rosier, who made the first accent, and companion, named Romaine, attempted to cross the Channel from Boulogne to England. Under the principal balloon, which was filled with hydrogen, they had suspended another, a smoke balloon, for the purpose of increasing or diminishing at pleasure the ascensional power. After rising about about three thousand feet in fifteen minutes the whole apparatus took fire from the latter attachment, and the unfortunate voyagers were dashed to the ground and instantly killed.
This disaster however, did not dampen the courage of other aeronauts; and so numerous have balloon ascensions become, as now to be not an uncommon spectacle in the principal cities of Europe, and scarcely a novelty in America. Among those most distinguished on this side of the Atlantic, as aeronauts, are Messrs. Lauriat, Clayton, Durand and Wise, the latter of whom has, if we are not mistaken, made more than one hundred and fifty ascensions. A most graphic account of one of these went the rounds of the public journals some years since. Leaving Cincinnati, Ohio, late one afternoon, he rose to an immense height; entered a current of air blowing with a whirlwind velocity; remained suspended all one night, and well-nigh frozen to death; and after the most singular experiences, landed next morning somewhere on the frontiers of North Carolina. I am not aware that any catastrophe has attended the many daring adventurers of America, although M. Lauriat was once dangerously soused in Boston harbor.
Somewhat large expectations were entertained at one time that balloons might be made to sub serve several important purposes of science and utility. These, however, have not hitherto been realized. The great lack and desideratum is a controlling and guiding power over the machine while in the at¬mosphere. In one or two instances, however, they have been successfully used in military reconnaissance. The victory of Fleurus, obtained in 1794, by the French, under Jourdan, over the Austrians, is attributed to knowledge acquired by the French commander, of the enemy's movements, by means of a balloon.
Some interesting facts in science also have been elicited by the same means. In 1804, Gay Lussac and Biot made some ascensions, with a view to meteorological observations in the upper strata of the atmosphere. In one ascent they found that at an elevation of between ten and thirteen thousand feet, the oscillations of the magnetic needle were performed at the same time as at the surface of the earth. At twelve thousand eight hundred feet, the thermometer, which stood at sixty-three and a half degrees at the observatory, had sunk to fifty-one degrees of Fahrenheit, being a decrease of one degree for every thousand feet. The dryness was pro-portional to the elevation. In another ascent, the variation of the compass, at the height of twelve thousand six hundred and eighty feet, remained unaltered, At fourteen thousand four hundred and eighty feet, a key, held in the magnetic direction, attracted with one end, and repelled with the other, the north pole of the needle. The same phenomenon was observed at twenty thousand one hundred and fifty feet. At eighteen thousand feet, the thermometer fell to freezing-point, and at twenty-two thousand nine hundred and twelve feet, seventeen degrees lower. At above twenty-three thousand feet, an empty flask was opened and filled with the air of that elevation, and on a subsequent analysis, gave the same proportion of the constituent gases as at the surface of the earth. These philosophers reached the highest point yet attained by man about twenty-three thousand feet, or four and a quarter miles above the sea—considerably higher than the loftiest peak of the Andes.
The above facts, it is believed, comprise all that has accrued to science by areonautic expeditions. The difficulty of steering the balloon at will have hitherto operated to prevent its use for any higher purpose than the gratification of curiosity. It has, however, been suggested that the buoyant gas be manufactured from coal, a much cheaper material, and the feats of Mr. Green has drawn public atten-tion anew to the subject. That gentleman, with two companions, ascended from Vauxhall, London, with a stupendous balloon, carrying with him a ton of ballast; crossed the Channel, and after a flight of eighteen hours, descended safely in the territory of Nassau, in Germany. This bold adventurer into ether, if we remember rightly, has since met a terri¬ble death, being dashed to pieces by a fall from a tremendous elevation. The immense aerial ship, building a few years since at Hoboken, perished, moriens nata, we believe.
But who, in view of the constant advance of inventive science, may say that human ingenuity will
not eventually overcome the obstacles at present attending atmospheric navigation, and render the balloon as common a vehicle of conveyance as are now the steamboat and locomotive drawn car? To the eyes of a former generation; the latter would seem as great a wonder as regular lines of balloons could possibly be at the present day. It may perhaps be the destiny of some successor of James Watt to achieve the performance of establishing such a mode, of conveyance, and thus rendering the balloon something more utilitarian than at present it seems to be— a sublime but profitless philosophic toy.
Source: 1856 New York Journal