One November night in the year 1782, so the story runs, two brothers sat over their winter fire in the little French town of Annonay, watching the grey smoke-wreaths from the hearth curl up the wide chimney. Their names were Stephen and Joseph Montgolfier, they were papermakers by trade, and were noted as possessing thoughtful minds and a deep interest in all scientific knowledge and new discovery. Before that night—a memorable night, as it was to prove—hundreds of millions of people had watched the rising smoke-wreaths of their fires without drawing any special inspiration from the fact; but on this particular occasion, as Stephen, the younger of the brothers, sat and gazed at the familiar sight, the question flashed across his mind, “What is the hidden power that makes those curling smoke-wreaths rise upwards, and could I not employ it to make other things rise also?”
Then and there the brothers resolved on an experiment. They made themselves a small fire of some light fuel in a little tin tray or chafing-dish, and over the smoke of it they held a large paper-bag. And to their delight they saw the bag fill out and make a feeble attempt to rise. They were surely on the eve of some great invention; and yet, try as they would, their experiment would not quite succeed, because the smoke in the bag always became too cool before there was enough in it to raise it from the table. But presently, while they were thus engaged, a neighbour of theirs, a widow lady, alarmed by seeing smoke issuing from their window, entered the room, and after watching their fruitless efforts for some while, suggested that they should fasten the tray on to the bottom of the bag. This was done, with the happy result that the bag immediately rose up to the ceiling; and in this humble fashion the first of all balloons sailed aloft.
That night of 1782, therefore, marks the first great step ever made towards the conquest of the sky. But to better understand the history of “Aeronautics”—a word that means “the sailing of the air”—we must go back far beyond the days of the Montgolfier brothers. For in all times and in all ages men have wanted to fly. David wished for the wings of a dove to fly away and be at rest, and since his time, and before it, how many have not longed to take flight and sail away in the boundless, glorious realms above, to explore the fleecy clouds, and to float free in the blue vault of heaven.
And since birds achieve this feat by means of wings, man’s first idea was to provide himself with wings also. But here he was at once doomed to disappointment. It is very certain that by his own natural strength alone a man will never propel himself through the air with wings like a bird, because he is made quite differently. A bird’s body is very light compared with its size. The largest birds in existence weigh under thirty pounds. A man’s body, on the contrary, is very heavy and solid. The muscles that work a bird’s wing are wonderfully powerful and strong, far stronger in proportion than the muscles of a man’s arm. To sustain his great weight in the air, a man of eleven stone would require a pair of wings nearly twenty feet in span. But the possession of such mighty wings alone is not enough. He must also possess bodily strength to keep them in sufficient motion to prevent him from falling, and for this he would require at least the strength of a horse.
Such strength a man has never possessed, or can ever hope to; but even as it is, by long practice and great effort, men have succeeded at different times, not exactly in flying, but in helping themselves along considerably by means of wings. A man is said to have flown in this way in Rome in the days of Nero. A monk in the Middle Ages, named Elmerus, it is stated, flew about a furlong from the top of a tower in Spain, another from St. Mark’s steeple in Venice, and another from Nuremburg. But the most successful attempt ever made in this direction was accomplished about 200 years ago by a French locksmith of the name of Besnier. He had made for himself a pair of light wooden oars, shaped like the double paddle of a canoe, with cup-like blades at either end. These he placed over his shoulders, and attached also to his feet, and then casting himself off from some high place, and violently working his arms and legs so as to buffet the air downwards with his paddles, he was able to raise himself by short stages from one height to another, or skim lightly over a field or river. It is said that subsequently Besnier sold his oars to a mountebank, who performed most successfully with them at fairs and festivals.
But it was soon clear that the art of human flight was not to be achieved by such means; and when men found that they were unable to soar upwards by their own bodily strength alone, they set about devising some apparatus or machine which should carry them aloft. Many ancient philosophers bent their minds to the inventing of a machine for this purpose. One suggested that strong flying birds, such as eagles or vultures, might be harnessed to a car, and trained to carry it into the sky. Another gravely proposed the employment of “a little imp”—for in those days the existence of imps and demons was most firmly believed in. A third even went so far as to give an actual recipe for flying, declaring that “if the eggs of the larger description of swans, or leather balls stitched with fine thongs, be filled with nitre, the purest sulphur, quicksilver, or kindred materials which rarefy by their caloric energy, and if they externally resemble pigeons, they will easily be mistaken for flying animals.” (!)
The first man who appeared to have any inkling of the real way of solving the problem of a “flying chariot,” and who in dim fashion seems to have foreshadowed the invention of the balloon, was that wonderful genius, Roger Bacon, the Learned Friar of Ilchester, the inventor or re-inventor of gunpowder, who lived in the thirteenth century. He had an idea—an idea which was far ahead of his times, and only proved to be true hundreds of years after—that the earth’s atmosphere was an actual substance or “true fluid,” and as such he supposed it to have an upper surface as the sea has, and on this upper surface he thought an airship might float, even as a boat floats on the top of the water. And to make his airship rise upwards to reach this upper sea, he said one must employ “a large hollow globe of copper or other similar metal wrought extremely thin, to have it as light as possible, and filled with ethereal air or liquid fire.”
It is doubtful whether Bacon had very clear ideas of what he meant by “ethereal air.” But, whether by accident or insight, he had in these words hit upon the true principle of the balloon—a principle only put into practice five centuries later. He saw that a body would rise upwards through the air if it were filled with something lighter than air, even as a body will rise upwards through the water if it is made of, or filled with, something lighter than water. We know that if we throw an empty bottle tightly corked into the sea it does not sink, but rises upwards, because it is filled with air, which is lighter than water. In the same way exactly a light bag or balloon which is filled with some gas which is lighter than air will not stay on the surface of the ground, but will rise upwards into the sky to a height which depends upon its weight and buoyancy.
Later philosophers than Bacon came to the same conclusion, though they do not seem to have seen matters more clearly. As recently as 1755 a certain learned French priest actually suggested that since the air on the top of high mountains is known to be lighter than that at an ordinary level, men might ascend to these great heights and bring down the light air “in constructions of canvas or cotton.” By means of this air he then proposed to fly a great machine, which he describes, and which seems to have been as large and cumbersome as Noah’s Ark. Needless to say, the worthy Father’s proposal has never yet been put into practice.
But it is time now that we return to the two brothers Montgolfier and their paper-bag of smoke. Their experiments proved at once that in smoke they had found something which was lighter than air, and which would, therefore, carry a light weight upwards. But of what this something was they had, at the time, but a confused idea. They imagined that the burning fuel they had used had given off some special light gas, with the exact nature of which they were unacquainted. The very word gas, be it here said, was in those days almost unknown, and of different gases, their nature and properties, most people had but the very vaguest notions.
And so for some time the Montgolfiers and their followers supposed that the presence of this mysterious gas was necessary to the success of their experiments, and they were very careful about always using special kinds of fuel, which they supposed gave off this gas, to inflate their bags. Later experiments proved, however, what every one now knows, that the paper-bag rose, not because of the gases given off by the fire, but by reason of the hot air with which it became filled. Nearly all substances, no matter how solid, expand more or less under the influence of heat, and air expands very greatly indeed. By thus expanding heated air becomes lighter than the surrounding air, and, because it is lighter, rises upwards in the atmosphere, and continues to rise until it has once more regained the average temperature.
Encouraged by the success of their first humble experiment, the Montgolfiers next tried their paper-bag in the open air, when to their delight it sailed upwards to a height of 70 feet. The next step was to make a much larger craft of 600 cubic feet capacity and spherical in shape, which they called a “Balloon,” because it was in appearance like a large, round, short-necked vessel used in chemistry which was technically known by that name. This great bag, after being inflated, became so powerful that it broke loose from its moorings, and floated proudly upwards 600 feet and more, and came down in an adjoining field. After a few more successful trials the brothers thought that the time had come to make known their new invention. Accordingly they constructed a great balloon of 35 feet in diameter, and issued invitations to the public to come and see the inflation. This was successfully made over a fire of chopped straw and wool, and the giant rose up into the sky amid the deafening applause of a huge multitude, and after attaining a height of 7000 feet, fell to the ground a mile and a half away.
The news of this marvellous event spread like wild-fire throughout the kingdom, and soon not only all France, but all Europe also, was ringing with the tidings. The French Royal Academy of Sciences immediately invited Stephen Montgolfier to Paris, and provided him with money to repeat his experiment. He accordingly constructed a yet larger machine, which stood no less than 72 feet high, had it most magnificently painted and decorated and hung with flags, and sent it up at Versailles in the presence of the King and all his court.
This particular balloon is noteworthy as having been the first of all balloons to carry living passengers into the air. They were three in number, a sheep, a cock, and a duck. Breathlessly the assembled multitude watched these innocent victims placed in the basket and soar calmly and majestically above their heads; and eagerly they followed the balloon to where it fell half a mile away to learn their fate. Would they have been suffocated in those upper regions of the air which no human being had yet explored, or would they be dashed to pieces in the descent? But they found the trio quite uninjured; the unimaginative sheep grazing quietly, and the duck cheerfully quacking. Forthwith the cry then arose that it was time for a man to hazard the ascent, and King Louis, who, like every one else, was vastly excited over the wonder, suggested that two criminals then lying under sentence of death should be sent aloft.
But now a brave French gentleman—M. Pilâtre de Rozier, a name ever to be remembered in the history of the conquest of the air—uprose in indignation. “Shall vile criminals have the first glory of rising into the sky!” he cried, and then and there he proudly claimed for himself the honour of being first among mortals in the history of the world to sail the air. His courageous resolve was wildly applauded, and forthwith preparations were commenced for the new venture. A yet larger balloon was made, in height as tall as a church tower, with a mouth 15 feet across. Around the mouth was fastened a gallery of wicker-work, three feet wide, to hold the passengers, and below all was slung with chains an iron brazier of burning fuel.