IX NAVIGATING THE AIR

IF it were possible to regard all medieval literature without more than a grain of doubt, we must believe that aerial flight by human beings was accomplished long before science had risen even to the dignity of acquiring its name. Thus, it is recorded by a medieval historian that during the reign of Charlemagne some mysterious persons having acquired some knowledge of aerostatics from the astrologers, who were credited with numerous supernatural powers, constructed a flying-machine, and compelling a few peasants to enter it, sent them off on an aerial voyage. Unfortunately for the unwilling voyagers, so the story runs, they landed in the city of Lyons, where they were immediately seized and condemned to death as sorcerers. But the wise bishop of the city, doubting the story of their aerial journey, pardoned them and allowed them to escape.

That such a fabulous tale could gain credence is explained by the prevailing belief in the powers of the astrologers and sorcerers at that time. People who could seriously believe that an alchemist could create gold and prolong life and youth indefinitely, would find nothing startling in the announcement that he could also perform the relatively simple feat of flying—a thing that birds and bats accomplish with such obvious facility. And nothing is more certain than that attempts at aerial flight have been made at various times since the beginning of history.

As with almost everything else in the matter of modern scientific advancement, the mysterious writings of the monk, Roger Bacon, are supposed to contain passages to show that the worthy friar had an inkling of the secret of air navigation. But he himself admits that he had only a theoretical knowledge of the subject, and had never seen a flying-machine of any kind in actual flight.

Much more definite and tangible are the designs of possible flying-machines still extant in the sketch-book of Leonardo da Vinci, made in the fifteenth century. From Leonardo's sketches it appears that the artist had conceived the idea of constructing jointed wings to be worked with strings and pulleys, the motive power to be that of a man's arms and legs. It appears also that later he had very definite ideas as to the possibilities of an aerial screw, and he is believed to have constructed one of these screws made on the same general plan as that of the ordinary type of windmill in use at that time. But nothing of practical importance came of any of Leonardo's experiments.

It is probable that his abandonment of the project of flying by means of wings worked by muscular force was due to the discovery that the strength of the muscles of even the strongest man was relatively slight as compared with the corresponding muscle of birds. Leonardo was peculiarly capable of discerning this discrepancy in strength, since he himself was one of the strongest men of his time. It is said that he could bend and straighten horseshoes with his hands. But in his experiments with the aerial screw he probably discovered very soon that even such muscular force as he was capable of exerting was entirely inadequate; and there being no other mode of producing power at that time, the idea of aerial navigation by this means was also abandoned.

About this time some imaginative persons, realizing the possibilities of muscular development when begun in childhood and persistently practiced, attempted the development of a race of men whose abnormally strong pectoral muscles would enable them to use artificial wings for flying. For this purpose a certain number of young boys were selected and constantly drilled in exercises of flapping the arms, to which broad sails were attached. These attempts were persisted in for several years, and it is said that some of these boys became so expert that by skipping along the surface of the ground and vigorously flapping their wing-attachments, they could travel at incredible speed, although never able actually to rise from the ground.

In 1678, a Frenchman named Besnier invented a flying-machine that is credited with being more successful than any hitherto attempted. His machine consisted of two bars of wood which were so hinged to a man's shoulders that they could be worked up and down by movements of the hands and feet. At the ends of these two bars were muslin wings made like shutters, so arranged that they were opened by a downward stroke and closed automatically by a reverse motion. The general appearance presented by these wings was that of four book-covers fastened by their backs to the ends of the bars, opening and closing alternately as the bars were worked up and down.

The inventor began his experiments in a modest way. His first attempt at flight was by jumping from a chair; next he tried a table; and finally, emboldened by his success, he made flights from window-sills and even house-tops. On one occasion he is said to have sailed from his attic window over the roof of a neighboring cottage, alighting, without injury, some distance beyond. It was even rumored at one time that he would try to fly across the Seine, but if such a feat was ever contemplated, it was never attempted.

Half a century later, however, the Marquis de Bacqueville actually made such an attempt with a machine somewhat similar to that of Besnier. The marquis had practiced in private with his machine with such encouraging results that he felt confident the feat was not an impossible one—in fact, that he was sure of accomplishing it. He therefore announced publicly that at a certain time the attempt would be made, and on the appointed day an immense crowd of people gathered on the banks of the river to witness the spectacle. Starting from a building some little distance away from the stream, the marquis made good progress at first, but just as he reached the river-bank his machine collapsed and he was tumbled out, alighting on a barge moored at the edge of the stream. Fortunately, the only injury he sustained was a broken leg; but this single attempt seems to have satisfied his aeronautic ambitions.

Until this time all attempts made at aerial flight had been those in imitation of birds; but during the early part of the eighteenth century the idea of the balloon was developed. This was the result of the numerous important discoveries made about that time as to the qualities of the atmosphere, and also several other "airs," as gases were called, such as their expansion and contraction under different conditions of temperature.

In 1766 the English philosopher, Henry Cavendish, discovered that hydrogen gas has only about one-seventh the weight of an equal bulk of air, this scientific discovery pointing naturally to balloon construction, since obviously if such a light gas were confined in a suitable receptacle, the device would rise to a certain height through the heavier atmosphere, as a cork rises through water. At the same time the experiments of the chemist, Dr. Joseph Black, and those of his younger contemporary, Doctor Priestly, were directed along the same lines, all of them pointing to the possibility of constructing an aerostat with buoyancy and lifting-power, and Priestly's Experiments Relating to the Different Kinds of Air is said to have been directly responsible for stimulating the efforts of Stephen and Joseph Montgolfier, the French paper manufacturers, who finally invented and sent up the first balloon.

Even before Montgolfier's invention, Tiberius Cavallo, an Italian living in England, had demonstrated the possibility of making toy-balloons. But the balloons of Cavallo were small affairs made of bladders or paper bags filled with hydrogen gas. One of these materials being too heavy and the other too porous for successful balloon construction, the performances of these toy-balloons were not conclusively demonstrative.

THE BALLOON INVENTED

Throughout the entire spring of 1783, all Auvergne, in France, was kept in breathless expectancy by constant rumors that the two Montgolfiers had really solved the problem of aerial flight, and would soon be seen soaring over the country in a strange birdlike machine. Rumor pictured this machine in various forms and sizes, but in point of fact there was really very little secrecy on the part of the inventors themselves, who frankly explained the principle of the balloon they were constructing. It was hardly to be expected, however, that most persons would believe the plain truth that so simple a device as a bag filled with hot air would do what had long been considered impossible.

Spring advanced and lapsed into summer, however, and as no flying-machine made its appearance, public clamor became so loud that the Montgolfiers felt they could postpone their demonstration no longer, although the balloon they were working on was not completed to their entire satisfaction. Nevertheless, they fixed on the definite date of June 5, (1783) as the day and Annonay as the place for making the trial, and their faith in their invention was shown by the fact that special invitations were sent to the leading persons in the vicinity, and a general invitation extended to the world at large.

But in place of some complicated and birdlike machine, as rumor had pictured the flying-machine, the multitude that gathered about the starting-point found only an immense cloth bag about thirty-five feet in diameter, without machinery or wings, and capable of containing some twenty-two thousand cubic feet of air, which the Montgolfier brothers and their assistants were inflating with heated air. As the bag filled, one of the brothers announced with all seriousness, that as soon as it was completely filled it would "rise to the clouds," carrying with it a frame weighing some three hundred pounds.

This announcement was not received with the same seriousness with which it was given. The idea of expecting anyone to believe that an ordinary cloth bag would fly excited the risibilities even of the more serious members of the crowd. Nevertheless, as the great globe filled it became evident to the spectators that it was tugging at the restraining ropes in efforts to rise, in a most extraordinary manner; and when, at a signal from the inventors, the ropes were cast off and the monster shot skyward, the crowd's smiles were turned to expressions of gaping astonishment. Straight into the air the monster mounted, and then, wafted by a gentle breeze, it continued to soar and rise until in ten minutes it had reached an altitude of six thousand feet, sailing easily in a horizontal direction for a short distance, then gradually descending and alighting some eight thousand feet from the starting-point.

The news of this triumph travelled quickly to Paris, and the Parisians clamored to see the wonderful performance repeated in the capital. The king and court were as interested as the savants and the populace, and an order was sent at once by his Majesty, bidding the brothers bring their balloon to the city.

In the meantime, however, a savant named Charles had started the construction of a balloon that was to be filled with hydrogen gas instead of heated air. This was a much more expensive undertaking, as a thousand pounds of iron filings and five hundred pounds of sulphuric acid were necessary to manufacture a sufficient quantity of gas to fill the varnished silk bag. But by the 23rd of August everything was in readiness for the filling process, and the following day this first gas-balloon rose from the Champs de Mars to a distance of three thousand feet and disappeared into the clouds. Three-quarters of an hour later it descended in a field near the little village of Gonesse, to the great consternation of the inhabitants of the neighborhood, who supposed it to be some monster bird, animal, or flying dragon. Arming themselves with scythes and pitchforks, therefore, but keeping at a safe distance, the boldest of the peasants sallied out and surrounded the field in which the creature had alighted. As it made no offensive movement, however, one bold huntsman armed with his trusty fowling-piece, crept cautiously within range and fired, tearing a hole in the monster's side and causing it to writhe and collapse, giving off what appeared to be a foul-smelling, poisonous gas in its death-struggles. When finally it lay flat and still the villagers became emboldened, and rushing upon it cut and tore it to shreds, ending the performance by tying the fragments to a horse's tail and sending the animal scurrying across the fields.

In anticipation of some such demonstration as this, the French Government had sent out a proclamation on the day of the ascent. "Anyone who should see in the sky a globe, resembling the moon in an eclipse," the proclamation ran, "should be aware that far from being an alarming phenomenon, it is only a machine, made of taffeta, or light canvas covered with paper, that cannot possibly cause any harm, and will some day prove serviceable to the wants of society." But apparently none of the villagers of Gonesse had seen this proclamation.

The success of these balloon ascensions sent a wave of enthusiastic interest in aeronautics all over France. The novelty and possibilities of ballooning appealed to the French temperament, just as the possibilities of submarine navigation and automobiling did a century later. As a result, France became at once the centre of ballooning, the whole nation being eagerly absorbed in the subject of navigating the air. In the theatre of action, the Montgolfiers continued to occupy the centre of the stage, and at all times showed themselves worthy of the leading rôle. Pursuant to the order of the king, M. Montgolfier had come to the capital, and on September 19th, before Louis XVI and his queen and the court at Versailles, sent up another hot-air balloon, or "Montgolfier," as this kind of balloon had come to be called.

A novel and important feature of this exhibition, however, was the substitution of living animals for sand-bags or other ballast, as used heretofore. In a wicker cage a cock, a duck, and a sheep were fastened, and these were carried some fifteen hundred feet into the air, descending uninjured, two miles from the starting-point, a few minutes later. The cage was broken open in the descent, but its occupants escaped injury, and the sheep was found quietly grazing when the rescue party arrived.

The successful voyage of these caged animals stimulated the balloonists to attempt the crucial test of sending up a balloon carrying a human passenger. But from this perilous undertaking the boldest spirits recoiled, even the Montgolfiers refusing to venture. In those days, however, there was always a means of securing human beings, willing or otherwise, for any undertaking. Where gold would not tempt, it needed but a word of the monarch to commute the death-sentence of some criminal, placing him at the disposal of the scientists for a better or worse fate than the gallows, as the case might be. And so when Louis XVI heard of the plight of the balloon-makers, he came to their assistance with the offer of two condemned prisoners to be sent on the first aerial voyage. This offer had an unexpected effect. The pride of a certain high-minded aeronaut named Rozier, who had hitherto refused to risk his life, was touched at the thought of criminals performing an act that all honest men refused. "What! are vile criminals to have the glory of being the first to ascend into the air?" he exclaimed. "No, no, that must not be." And forthwith he offered his own services for the hazardous undertaking.

The royal decree was accordingly repealed, to the chagrin of the criminals, no doubt, and preparations made for the momentous attempt. Montgolfier was engaged to construct a large balloon, and on the 15th of October, 1783, the trial was made in a garden in the Faubourg St. Antoine. Let no one suppose, however, that this first man-carrying balloon was cut loose from the earth and sent skyward to shift for itself, as might be gathered from the reluctance of persons to make the ascent. On the contrary, the balloon was held by strong cables, and allowed to rise only to a height of eighty feet—to the level of some of the lower windows of a modern sky-scraper—the aeronaut keeping it afloat for about five minutes by burning wool and straw in a grate made for the purpose.

Those who have witnessed the reckless manner in which the modern balloonist mounts thousands of feet into the air, seated on a trapeze or clinging to flying rings attached to an old balloon, patched and frequently rotten, may be inclined to sneer at the brave Rozier. But it should be remembered that in 1783 people had not learned nineteenth-century contempt for altitude. Furthermore, no one could tell what might be the effect upon the human system of ascending to a great height when away from a building or other terrestrial object. Fainting, hemorrhages, heart-failure, and death had been predicted, and could not be practically refuted. In short, it was an absolutely new and untried field; and it required far greater courage on the part of Rozier to mount eighty feet in a captive balloon than for a modern aeronaut to sail thousands of feet skyward. In proof of this is Rozier's subsequent record of ascents in free balloons, and dangerous voyages, in the last of which he lost his life.

To France, therefore, belongs the honor of inventing the balloon and being first to test it with a human passenger. On this last point, however, France only eclipsed America by a few days. For while the craze for balloon-making was at its height in France during the summer of 1783, a somewhat similar craze on a small scale had started in some of the American cities. Two members of the Philosophical Academy of Philadelphia, Rittenhouse and Hopkins, constructed a peculiar balloon having forty-seven small bags inflated with hydrogen attached to a car. On November 28th, six weeks after Rozier's ascent, this balloon was sent up, with James Wilcox, a carpenter of Philadelphia, as passenger. Everything was going well with the voyager until he suddenly discovered that the wind was wafting him toward the Schuylkill River, which so alarmed him that in attempting to descend quickly he punctured the bags so freely that he came to the ground with considerable force, escaping, however, with a dislocated wrist.

Meanwhile, in Europe, a new danger to balloonists had arisen. Fanaticism was rife, particularly in the vicinity of Paris, and many members of the cloth were tireless in denouncing this "tampering with God's laws by invading the inviolability of the firmament." Fortunately, the king took a broader view, and his soldiers were supplied freely for protecting balloonists and their property; but even with this protection both were roughly handled at times.

By this time England had become aroused; balloon-making became popular across the Channel, and some new records for time and distance were soon made. One balloon sent up in London landed in Sussex, forty-eight miles away, making the voyage in two hours and a half. A few days later a small balloon sent up in Kent was blown across the Channel and landed in Flanders. But neither of these balloons carried passengers.

As yet there had been few serious attempts at constructing dirigible balloons, but now Jean-Pierre Blanchard opened a new era of experiments by combining an ordinary balloon for obtaining the lifting power with wings and rudder. In this balloon there was also placed an umbrella-shaped sail interposed horizontally between the car and the body of the balloon, which was to act as a sort of parachute in case of accident. On the first voyage in this balloon Blanchard was to have had for companion a Benedictine monk; but as the machine began to rise from the ground the monk was seized with fear, turned deadly pale, crossed himself, and seemed about to collapse. Fortunately at this moment a leak was discovered in the balloon and it was accordingly lowered for repairs. When these were completed the aeronaut decided to dispense with the company of the monk, who was only too willing to gratify his wish. But just as the car was again ready to start, a stripling student from the Military Academy forced his way through the crowd, jumped into the car, and announced his intention of making the ascent. Being ordered from the car by Blanchard, he declared that he had the king's license, and when asked to produce it he drew his sword, declaring that this was the license he referred to. By this time the crowd had lost patience; some one seized the young man unceremoniously by the collar, hauled him from the car, and turned him over to the police.

A few years later particular attention was called to this incident by a rumor, which finally grew into a fixed belief in France, that the young military student in question was none other than the youthful Napoleon Bonaparte, then a student at the Academy. Throughout the entire reign of the emperor this was the general belief, and if it was denied at all by Napoleon, the denial was not made with due emphasis. At St. Helena, however, the captive emperor finally stated definitely that he was not the hero of this escapade, who is now known to have been a student by the name of Chambon.

Nothing of importance came of Blanchard's first attempt at guiding a balloon with rudder and wings, except perhaps to emphasize the fact that wings of an oarlike type were useless for propulsion; but nevertheless Blanchard soon prepared a somewhat similar balloon in which he proposed to steer himself across the English Channel. Before this time, as will be remembered, several balloons had crossed the Channel, but none of them had carried passengers. On this voyage Blanchard proposed to make the attempt, taking with him as companion an American physician named Jeffries. On January 7, 1785, these two embarked from the cliffs of Dover, a strong wind at the time setting toward the French coast. Before their journey was half completed they discovered that an insufficient amount of ballast had been shipped, and that the balloon was gradually descending at a rate which would land them in the Channel several miles from shore. To avert this calamity they were obliged to throw out everything in the car—books, provisions, anchors, ropes, the "wings" that were intended for guiding, and also most of their garments. They were, indeed, about to cut loose the car itself, and climb into the shrouds, when suddenly the balloon, caught by a fresh current of air, began to rise, and was wafted to a safe landing place. This was the most daring exploit as yet performed by the aeronauts.

Although at least fifty different persons had made more or less extended aerial voyages during the two years that had intervened since the invention of the first balloon, no one of them had been seriously injured. Indeed, this apparently most dangerous undertaking had been relegated to the grade of commonplace in popular opinion, owing to these fortunate results. But the world was soon to learn that its first estimates of the dangers of ballooning had not been exaggerated.

Since the invention of the Montgolfier balloon two distinct schools of balloonists had arisen, one of which favored the hot-air, and the other the hydrogen balloon. By the advocates of the hot-air balloon it was claimed that the relatively small expense, and the fact that the balloonist could descend at any time and renew his supply of fuel, made this the most desirable type, at least for long-distance voyages. By the advocates of the hydrogen balloon it was shown that the hot-air balloon must be constructed much larger to obtain the same amount of lifting power, could be maintained in the air for a comparatively short time at most, and was in constant danger from the fire that must be kept burning in the grate. In reply to this last charge the hot-air advocates pointed out that a tiny spark of electricity, which would not affect the hot-air balloon, might explode the hydrogen balloon, thus introducing an element of danger quite as great as that of the fire in the hot-air balloons.

As an outcome of these disputes, Pilatre de Rozier, the first man ever to make an ascent, proposed to attempt to cross the Channel in a new-type balloon, a combination of hot-air and hydrogen machine, which was supposed to represent the good qualities of both types. Several months were consumed in constructing it, and when finally completed he and a companion attempted to cross the Channel, as had been done by Blanchard and Jeffries a short time previously. All went well at first and the balloon was several miles on its journey when suddenly the wind changed, the balloon was blown back over the heads of the anxious watchers below, and when a short distance inland, suddenly burst into flames. At first it descended with an oscillating movement, and then, freed from the restraining silk and canvas, it shot downward, striking the earth with terrible force, the two occupants being killed. Thus the man to make the first ascent in a balloon was also the first to lose his life. Rozier himself seems to have expected some such ending to his voyages, and just before making his last ascent he remarked to a friend that, whatever the outcome, "one had lived long enough when one had added something to humanity."

The fate of Rozier and his companion being known, and the awful dangers of balloon ascensions thus forcibly brought home, there was a popular outcry against such attempts and efforts were made to pass laws forbidding them. But no such demand or suggestion came from the balloonists themselves. They could point to the fact that, while as yet the balloon had been of no importance commercially, it had at least been turned to some account in the field of science, which was simply a stepping-stone to commercial advancement. It had been the means of settling forever the question of temperature and rarefaction at different altitudes, besides numerous less important although no less interesting subjects.

While it was true that many of the experiments of the aeronauts had added largely to human knowledge, some of them were both dangerous and foolhardy. An exhibition of this kind of folly was given by the Frenchman, Testu-Bressy, who, wishing to test his theory that large animals would bleed from the nose at a much lower elevation than man, despite the thicker consistency of their blood, made an ascent mounted on the back of a horse. On this occasion the aeronaut did not, even take the simple precaution of tying the horse's feet to the car; and what seems most remarkable, the animal made the journey without moving or showing any sign of fear.

AN INTERNATIONAL BALLOON RACE.

This view was taken before the start of an international balloon race near Berlin. The balloons are of the ordinary non-dirigible type.

The time was at hand, however, when Montgolfier, who had always maintained that the true usefulness of the balloon would be in warfare, was given the opportunity of seeing his contention verified. On the breaking out of the French Revolution, balloon corps were at once pressed into the service of the army. Napoleon Bonaparte carried with him some balloons on his Egyptian campaign, partly for the purpose of making observations, and partly to impress the Arabs with the superiority of Christian armies. A school of aeronautics was established at Meudon, and some fifty young men, sworn to secrecy, assigned to it. Balloons were constructed, tested, and distributed among the different divisions of the army, and one of these was used for reconnoitering the position of the Austrian forces just before the battle of Fleurus. In the course of the day two ascents were made in this balloon, which was held captive by several thousand feet of cable. The second ascent drew the fire of the enemy's cannon, but the range was too great and no harm was done. Meanwhile the French general, Jourdain, was furnished most valuable information by these aerial voyages.

The Revolutionary wars were also responsible, indirectly, for the invention of the parachute. It will be recalled that even as early as the fifteenth century, Leonardo da Vinci had conceived the idea of a kind of parachute; and that Blanchard had a spread-canvas arrangement to produce a similar effect attached to some of his balloons. It was not until 1799, however, that the folding umbrella-like parachute was invented, the inventor, Garnerin, having developed the idea in trying to devise some means of escape from the fortress of Buda, Hungary, where he was being kept prisoner after one of the battles in the North between the Revolutionary forces and the Austrians and Prussians. Although he did not actually effect his escape in this dramatic manner, he finally proved that he had not dreamed in vain during his imprisonment by demonstrating the entire practicality of the parachute.

Garnerin's first practical test of his invention was made in October, 1797, when he ascended to the height of six thousand feet in a balloon to which was attached a parachute of the ordinary umbrella type still used. At that altitude he cut loose the balloon which rushed upward until it exploded, while the parachute, dropping rapidly at first, finally settled slowly and gently to the earth, without injury to the inventor.

PROGRESS IN MECHANICAL FLIGHT

The attempts at navigating a balloon having proved thus far so unsuccessful, many inventors now returned to the idea of producing a flying-machine which was independent of the inflated balloon. It was evident that the resistance presented by the great surface necessary in a balloon of sufficient size to have the required lifting power was such that no known efforts of propulsion could overcome this resistance even in the face of a slight breeze, to say nothing of a strong wind. The balloon was by no means abandoned, however, and two definite schools of aeronauts gradually came into existence, each having ardent advocates.

As early as 1784, the aeronaut Gérard had proposed a flying-machine which was to be made with body, wings, and steering apparatus, in which propulsion was to be accomplished by the use of escaping gas and gun-cotton. The inventor himself was so sanguine of the results, and so many contemporary inventors were of the same opinion, that when this machine proved to be an utter failure, the blow to the advocates of the flying-machine was so great that they did not rally from it for something like a quarter of a century. In 1809, however, a Viennese watchmaker named Degen revived interest in attempts at mechanical flight by inventing a flying-machine which consisted essentially of two parachutes. These were worked by hand, and the inventor was said to have been able to rise to a height of over fifty feet from the ground "moving in any desired direction."

These claims were not borne out in fact, but they stimulated an interest in the possibilities of mechanical flight, and in the parachute, which had never come into popular favor despite its successful use by the inventor, Garnerin. Hopes were again entertained that a modification of this device might be utilized in solving the problem of aerial flight, and in 1837 an aeronaut, Henry Cocking, invented a new type in which he proposed to descend from a balloon. The parachute of Garnerin, as we know, had been constructed like a huge umbrella, whereas Cocking's parachute had the general appearance of an umbrella held upside down. An unusual interest was aroused in the prospective experiment from the fact that a great majority of scientists did not consider that this parachute was constructed on correct scientific principles, and predicted that the aeronaut would be killed when he attempted to use it. Before the day of the trial arrived numerous articles had been published, presenting arguments for and against Cocking's device, and on the very day itself one of the newspapers contained a long article by a leading authority on aerostatics, reviewing the numerous reasons why the attempt would surely prove a failure.

Despite the protests of the majority of interested persons, however, Cocking and a companion named Green made the ascent at the appointed time. After rising to a certain height the parachute was cast off, the parachute's car containing the inventor, while Green remained in the balloon. Instead of sailing slowly toward the earth, however, the parachute fell rapidly, with an oscillating movement, gaining speed and jerking violently as it descended, until finally when several hundred feet in the air, Cocking was thrown from the car and dashed to pieces, while the wreck of the parachute landed a few yards away. Thus the predictions of the majority came true, although as we know now, the cause of the tragedy was due to faulty material rather than the design of the machine. For the American aeronaut, Wise, demonstrated a little later that parachutes built on the same principle as that of Cocking could be used successfully.

As we have seen, most of the flying-machines attempted heretofore took for their model the bird with flapping wings. There were certain persons, however, who had observed that this flapping movement was not essential to flight—that certain large-winged birds, such as buzzards and hawks, were able to soar in any direction at will, holding their wings rigidly. It was evident, therefore, that shape, position, and construction of the bird's wing played quite as important a part as the flapping movement. The lifting power of plane surfaces, or aeroplanes, was also carefully studied in this connection and in 1842 the inventor, Henson, constructed a flying-machine utilizing this aeroplane principle, his machine having thin, fixed surfaces, slightly inclined to the line of motion, and supported by the upward pressure of the air due to the forward movement.

Everyone will remember the distance to which a skilful juggler can project an ordinary playing-card by giving it a certain inclination in throwing. It will travel upward or on a level, and continue this direction until the force of the movement of throwing is exhausted. Obviously, if this force were self-contained in the card—if it could continue rotating and moving forward—it could fly indefinitely. Henson had studied and experimented with these miniature aeroplanes, and was convinced that if the same principle that governed their flight were to be applied to larger machines, practical flying-machines could be made.

"If any light and flat, or nearly flat, article," he wrote, "be projected edgeways in a slightly inclined position, the same will rise on the air till the force exerted is expended, when the article so thrown or projected will descend; and it will readily be conceived that if the article possessed in itself a continuous power or force equal to that used in throwing or projecting it, the article would continue to ascend so long as the forward part of the surface was upward in respect to its hinder part, and that such article, when the power was stopped, or when the inclination was recovered, would descend by gravity only if the power was stopped, or by gravity, aided by the force of the power contained in the article, if the power be contained, thus imitating the flight of a bird."

But when Henson attempted to fly in his elaborately planned and constructed flying-machine, it proved a complete failure. It showed a tendency to rise, but its lifting power was insufficient for the weight of the engine driving the propellers. It was evident, however, that if the power of the engine could be sufficiently increased, or, what amounts to the same thing, its weight sufficiently lightened, a machine built on the aeroplane principle could be made to fly. But at that time the lightest type of engine was a crude, heavy machine, and for the moment nothing more was attempted in producing a mechanical flying-machine propelled by steam.

Meanwhile the possibility of producing a dirigible balloon was again brought into prominence by the suggestion of two aeronauts, Scott and Martainville, to change the shape of the envelope of the balloon. Hitherto, all balloons had been made globular or pear-shaped—shapes that offered great resisting surfaces to the atmosphere. Now it was proposed to make them in the form of long, horizontal cylinders, with pointed ends, these cigar-shaped, or boat-shaped balloons offering much less resistance. But here, as in the case of the flying-machine, engines that were sufficiently strong to work the propellers were found to be too heavy for the balloon to lift. Meanwhile the aeroplane idea was brought into prominence from an unexpected quarter.

Among the numerous observers in the middle of the century who had noted the soaring power of birds, was a French sea-captain named Le Bris. On his long voyages he had studied the movements of the great albatross, which, with wings rigidly distended, outsailed the swiftest ship without any apparent exertion. Anxious to study the wing-mechanism of this bird, the captain, overcoming the scruples of the mariner against killing the sacred sea-rover, shot one of the birds. On removing a wing and spreading it in the wind he thought that it had a very appreciable tendency to pull forward into the breeze, and tended to rise when the wind was strong. Convinced that by duplicating the shape of the bird he could construct a successful flying-machine, Le Bris set to work and succeeded in producing a most remarkable "air-ship."

The body of this machine, which was supposed to correspond to the body of the bird, was made boat-shaped, and was about thirteen feet long and four feet wide, being broadest at its prow, in imitation of the breast of the bird. The front part was decked over, something like the bow of the modern torpedo-boat, and through this deck protruded a small mast which was used for supporting the pulleys and cords used in working the machinery of the wings. Each wing was about twenty-five feet long, so that the entire spread of the machine was fifty feet. There was a tail-like structure so hinged that it could be used for steering up, down, and sidewise, the total area of surface presented to the atmosphere being something over two hundred square feet, although the entire "albatross" weighed something less than a hundred pounds.

The front edges of the wings were made of pieces of wood fashioned like the wings of the albatross, and feathers were imitated by a frame structure covered with canton flannel. The front edges of the wings could be given a rotary motion to fix them at any desired angle by an ingenious device worked by two levers. In operating this artificial bird the captain proposed to stand in the boat and control its flight by these sets of levers and by balancing his body.

Having full confidence in the ability of his invention to soar once it had been given an initial velocity, the captain selected a morning when a good breeze was blowing and hired a cart-driver to carry him out into the neighboring fields. The machine was placed horizontally upon the cart and fastened to it with a rope which could be loosened by the pulling of a slip-knot held by the captain, who took his position in the boat. On reaching the open country the driver put his horse into a brisk trot when, the levers controlling the wings being set, the machine rose gracefully into the air and travelled forward a distance of perhaps a hundred yards. At this moment the running-rope in some unaccountable manner became wound about the body of the driver, hauling him unceremoniously from his seat, and dangling him writhing and shrieking at the end of the rope, several feet above the ground. As it happened, his weight was just sufficient to counterbalance the wind, so that acting in the capacity of the tail of a kite, he assisted materially, if involuntarily, in keeping the artificial bird in flight.

When the captain became aware of what was going on below, he altered the angle of the wings and came slowly to the earth, descending without accident either to himself or to his machine. All things considered, this was a remarkable performance, and it was so considered by people in the neighborhood, who made a hero of the gallant mariner. His next attempt, however, was less successful. Something went wrong with the machine shortly after starting, landing the inventor in a stone-quarry with a broken leg and a shattered machine. This accident also shook the courage of the captain, and for several years he made no more attempts at flight, confining his attention to sailing a coasting-vessel. But his faith in his "albatross" never wavered, even if his courage did for a time, and in 1867 he began building a more elaborate machine, aided by public subscriptions. The outlook for this new device seemed very promising, several fairly successful flights of perhaps two hundred yards having been made, when a sudden gust of wind catching up the machine one day during the momentary absence of the inventor, dashed it to pieces upon the ground. This was the final blow to the hopes of Captain Le Bris, who made no further attempts, his means and his energies being entirely exhausted.

GIFFARD, "THE FULTON OF AERIAL NAVIGATION"

Meanwhile the advocates of the dirigible balloon had not remained idle, many of them attempting to utilize the principle of the aeroplane in connection with a balloon. Some of these machines were of most fantastic design, but one in particular, that of Mr. Henri Giffard, succeeded so well, and proved to be dirigible to such an extent, that Giffard is sometimes referred to by enthusiastic admirers as "the Fulton of aerial navigation." In principle, and indeed in general appearance, this balloon was not unlike some of the balloons built by Santos-Dumont fifty years later. It had the now-familiar cigar shape, common to most modern dirigible balloons; and beneath was suspended a car carrying a steam-engine that worked a screw propeller. The rudder, placed at the stern just below the balloon in a position corresponding to the rudder of a ship, was a large canvas sail set in a frame. The envelope of the balloon was one hundred and fifty feet long and forty feet in diameter and contained about ninety thousand cubic feet of coal-gas. To lessen the danger of igniting this from the engine, Giffard arranged the chimney so that it pointed downward, and suspended it some forty feet below the envelope.

On September 24, 1852, he rose from the Paris Hippodrome, and succeeded in making a headway of from five to seven miles an hour in the face of a strong wind. In response to the rudder his balloon performed some difficult evolutions, turning right or left at the will of the operator. He continued his maneuvers for some time, and then extinguishing his fire, opened the valve and returned safely to the ground. This was a great victory for the advocates of the dirigible balloon, and was indeed a performance that has not until recently been surpassed in the fifty years that have intervened since that time. But despite this initial success, Giffard soon renounced the field of aeronautics, and no worthy successor appeared to take his place for more than a quarter of a century.

THE VOYAGES OF THE GIANT

One of the most remarkable balloons ever constructed, and one of the most remarkable voyages ever made in any balloon, was that of the mammoth aerostat constructed by the noted Parisian photographer, Nadar, in 1863. Nadar belonged to the school of aviators who opposed the principle of the balloon as against that of the aeroplane, and his idea in constructing this leviathan balloon was simply for the purpose of raising money so that he might build a practical flying-machine, constructed on the aeroplane principle, and which, he declared, would revolutionize air navigation. The Giant, he said, would be the last balloon ever constructed, as thereafter air-ships, made on the principle of the one he was about to construct, would supplant balloons entirely. His plan was to make the ascent in the Giant from some large enclosed field near Paris, and the admission price of one franc to be charged for entering the field was to supply funds for defraying the expense of building the Giant, the surplus to be used in constructing his flying-machine.

In making the Giant twenty-one thousand yards of silk were used, the balloon being over two hundred feet in height, with a lifting capacity of nine thousand pounds. It was built as a double balloon, one within the other, this being the idea of the aeronaut, Louis Godard, as a means of preserving the excess of gas produced by dilation at different altitudes, instead of losing this excess as was usual with balloons constructed in the ordinary manner. But perhaps the most interesting thing about this balloon was the structure of the car and its contents. Like the ordinary car it was constructed of wicker work, but was of the proportions of a small house, being built two stories high, with an upper platform like the deck of a ship, on which the passengers could stand. In the two floors below were a saloon, compartments for scientific instruments, sleeping-cabins, and practically all the conveniences of a small, modern house. In the car and suspended about it were wheels, guns, a printing-press, cameras, cages of carrier-pigeons, baskets of wine and provisions, games, and an "abundant supply of confectionery."

The first ascent was made from the Champs de Mars, and twenty-five thousand persons paid the admission fee to witness it. This did not by any means represent the number of persons on the field, as the barriers were broken down in many places early in the day, and a majority of the spectators thus gained free admission. Fifteen persons made the ascent upon this occasion, but instead of making a protracted voyage as intended at first, the balloon was brought to the earth at nine o'clock in the evening only a few leagues from Paris. It is said that this landing was made contrary to the wishes of Nadar, but in deference to the opinion of the Godard brothers, who believed that the balloon was being carried out to sea, whereas, in point of fact it was travelling due east, directly away from the Atlantic.

Three weeks later the second ascent was made, on this occasion eight instead of fifteen persons starting on the voyage. These were under the immediate command of Nadar, whose position was that of the captain of a ship on the high seas, and whose authority none might presume to question. A set of rules governing the conduct of those on board and setting forth explicitly the authority of the captain was posted in the cabin, the nature of some of these giving a cue to the peculiar attitude of mind of the originator of the scheme. For example, it was ordered that "Silence must be absolutely observed when ordered by the captain." "All gambling is expressly prohibited." "On landing no passenger must quit the balloon without permission duly acquired from the captain."

The ascent was again successful, the balloon travelling in a northeasterly direction during the night, all the passengers remaining awake and alert, having constantly in mind the danger of falling into the sea. The following morning on descending to a lower altitude through the clouds, the voyagers found that they were passing the border of Holland, near the sea. At this point an attempt was made to land, but a violent gale having arisen, the anchor cables were broken, and the car was dragged along the surface of the ground at terrific speed, striking and rebounding into the air, dragging through marshes and rivers, bruising and battering the occupants who were unable either to leave the balloon or to check its flight. As they were whirling across the country in this manner an immense forest came into view directly in their path, and believing that when this was reached every occupant of the car would be dashed to pieces against the trees, they decided to take their chances by leaping. One after another they jumped, striking the earth and turning over and over, breaking bones, and mangling faces and bodies. The only female occupant of the car, Mrs. Nadar, was fortunate in alighting in a river without serious injury. Others received only slight bruises or a severe jolting while the most unfortunate, M. St. Felix, had a broken arm, a dislocated ankle, and numerous cuts and bruises.

Later the Giant was captured many miles farther on and returned to its owners in Paris. Subsequently it made numerous voyages, none of which was particularly profitable, however, so that the purpose for which it was designed was not fulfilled, and Nadar's proposed air-ship was never constructed.

While the Giant was the largest balloon hitherto constructed, it broke no records either for speed attained or distance travelled, and much more notable performances in this respect had been made before its time and have been made since. Thus, one of Coxwell's balloons traveled from Berlin in the direction of Dantzig, covering the distance of one hundred and seventy miles in three hours. This was in 1849; and in the same year M. Arban crossed the Alps from Marseilles to Turin, covering the distance of four hundred miles in eight hours. In July, 1859, the American aeronaut, John Wise, sailed from St. Louis, Missouri, to Henderson, in New York State, in nineteen hours, travelling eight hundred and fifty miles at the rate of forty-six miles an hour. This was the longest voyage ever made until the time of the balloon-races started from the Paris Exposition, in 1900. On this occasion Conte de la Vaux, starting from Paris, remained in the air thirty-five hours and forty-five minutes, landing at Korosticheff, in Russia, 1193 miles from the starting-point, thus breaking all previous records.

EARLY WAR-BALLOONS AND DIRIGIBLE BALLOONS

Despite the fact that the "aviators"—the aeronauts whose efforts were directed to flight by mechanical means in imitation of birds, or by the use of what are now called aeroplanes—were in the field centuries before the balloon was invented, from the time of the first Montgolfier balloon until very recently, the balloonists had shown their rivals a clean pair of heels in practical results. A dirigible, man-carrying balloon that can be guided under favorable conditions, and can maintain itself in the air for any considerable length of time, was an accomplished fact at least five years before the practical aeroplane flying-machine. Yet the majority of scientists had become convinced several years before their convictions were verified by actual demonstration, that some type of mechanical flying-machine—a machine that is heavier than the atmosphere and that maintains itself by some mechanical means—was the only one likely to solve the question of aerial flight. Yet thus far balloons have rendered more actual service to man than flying-machines.

It will be recalled that balloons were used for making military observations during the French Revolution; and they were used for similar purposes in several of the Continental wars during the first half of the nineteenth century. After that time, however, interest in their use for this purpose flagged somewhat until the time of the Crimean War, when their usefulness was again demonstrated, as it was in the American Civil War which followed shortly after.

But it was not until the Franco-Prussian War that the one thing for which the Montgolfiers had predicted their usefulness in warfare—that of sending messages out from a closely besieged city—was put to practical test. During the siege of Paris by the Germans in 1870–71, when every other possible means of communication had been cut off, the Parisians still kept in communication with the outside world by means of balloons and carrier-pigeons. On September 23rd, the first ascent of the siege was made by the aeronaut Durouf, who carried a large number of despatches from the city, landing near Evreux, after being in the air about three hours. The success of this journey and several others that quickly followed led the French Government to establish a regular balloon-post, and to undertake the manufacture of balloons for this purpose. The mere matter of balloon construction offered no difficulty but a more serious one was met in the lack of experienced aeronauts. In this emergency, however, it occurred to the authorities that sailors, accustomed to climbing about at dizzy heights, might be taught to take the place of trained aeronauts. This experiment proved most successful, and in subsequent voyages these mariners maintained their reputation for daring undertakings. Between September and January sixty-four balloons were sent up, all but seven of which fulfilled their mission and delivered their despatches; and the total number of persons leaving Paris in balloons during the siege was one hundred and fifty-five. These carried with them a total of nine tons of despatches and something like three million letters, the speed with which these journeys were made ranging from a minimum of twenty miles an hour to a maximum velocity, in one instance, of eighty miles.

Shortly after this balloon-post was established, the Germans came into possession of the new Krupp long-range rifle, with which they succeeded in bringing down several of the balloons. Companies of Uhlans, the swiftest cavalry of Germany, scoured the country constantly, and kept such a sharp lookout that, as the German lines were extended, it became difficult for the balloons to make their way over them in daylight. Night voyages, therefore, became necessary; but naturally these were extremely dangerous, and many of them had dramatic and tragic terminations. One of the longest and most famous of these voyages was that of the balloon named the Ville d'Orléans, which left Paris about midnight of November 24th. As a strong wind was blowing from the north at the time, it was hoped that the balloon would descend in the vicinity of Tours. The first intimation that the voyagers had that there was a deviation from this course was the sound of the waves breaking against the shore beneath them. At this time they were in a thick mist, and it was not until some time after daybreak that this mist cleared away sufficiently for them to get an idea of their surroundings. Then they found, to their horror, that they were over a large body of water, out of sight of land, in what part of the world they had not the slightest idea. The balloon appeared to be drifting rapidly, and from time to time they passed over vessels, which were frantically signaled by the voyagers. No notice was taken of these signals except by one vessel, which responded by firing several shots which went wide of the mark. The balloon continued on its course northward until late in the day when land was sighted lying to the northeast. By this time the ballast in the car had been entirely expended, and the balloon, which had been sinking gradually for several hours, seemed about to plunge into the ocean. In this extremity a heavy bag of despatches was thrown out, and the balloon thus lightened again rose to a considerable height, where another current of air carried it over the land.

A successful landing was made in Norway, in a desolate but friendly region, where the balloonists were treated with the greatest kindness. The balloon and its contents were subsequently secured, and all the despatches delivered to their proper destinations, except, of course, the one package that had been thrown out as ballast.

A week after the eventful voyage of the Ville d'Orléans a still more unfortunate ascent was made by a sailor named Prince, in the balloon called the Jacquard. As the ropes releasing this balloon were cut, the enthusiastic mariner, standing in his car and extending his hand toward the crowd, shouted dramatically, "I go upon a great voyage!" He did—and on one much greater than he anticipated—for the balloon was blown out to sea and lost. As he was passing over England after successfully crossing the Channel, he threw out his package of despatches, but this so lightened his balloon that it mounted quickly and was soon far out over the Atlantic. It was never heard of again. But the life of the enthusiastic voyager was not given in vain, for most of the despatches eventually reached their destination.

Although, as has been seen, the balloons sent out of Paris were not of the dirigible kind, and were entirely dependent upon the caprice of the winds, they fulfilled their missions quite as well as could be expected under the circumstances. In fact, there was small chance of failure, starting as they did from a central point, and being almost certain of success no matter what direction was taken, except, indeed, the one that would blow them over the German frontier. But the other part of the problem—the sending of balloons from the outside into Paris—was an entirely different proposition. So different, and so difficult, in fact, that it was never accomplished, although attempted several times.

But the millions of people in Paris, shut off completely from the outside world, were just as anxious to receive news as to send it. In attempting to establish communication from without, therefore, one balloon leaving the city in the early days of the siege, carried with it some trained dogs in the hope that they would make their way back to the city through the German lines. But either they lost their way, or were captured by the enemy, for nothing was ever heard of them after starting on the return trip. In this extremity the members of the "Société Colombophile" came forward with the offer of the use of their homing-pigeons. The society had a large number of these birds, trained to return to their cotes from long distances, and the experiment of sending return despatches with them was tried at once. Three birds were first sent out in one of the despatch-balloons, and within sixteen hours after starting these had all returned to the capital, bearing despatches. During the next few days a score more pigeons were sent out, eighteen of which returned safely with their messages; and thereafter a regular pigeon-post was organized.

As the weight that a pigeon is able to carry in its flight is extremely small, microscopic photography was resorted to, so that, although each bird carried only a single quill in which were rolled thin collodion leaves, the whole weighing only fifteen grains, the amount of printed matter thus carried was sometimes more than is contained in an ordinary volume.

By photographic methods, thirty-two thousand words, or about half an ordinary volume, were crowded upon a pellicule two inches long by one and one-quarter inches wide, and weighing about three-quarters of a grain! Twenty of these, representing six thousand words, or twice the amount of printed matter contained in such a book as Scott's Ivanhoe, or Prescott's Conquest of Mexico, were carried by each pigeon. One bird carried forty thousand complete messages on a single trip.

When the bird arrived at its cote, the quill was secured and taken to the government office, where the little leaflets were carefully removed, placed in an enlarging optical apparatus, thrown upon a screen with a magic lantern, and copied. The messages were then distributed to their destination about the city.

THE DIRIGIBLE BALLOON ACHIEVED

By this war, France, the home of the balloon, was brought keenly to realize the advantages and the limitations of such flying-machines; and it was but natural, under the circumstances, that as soon as peace was restored, efforts should be made there to produce a dirigible balloon, or some other form of dirigible flying-machine. Giffard, as we have seen, had been fairly successful; and now M. Dupuy de Lome, chief naval constructor of France, took up the problem. He constructed a balloon with a cigar-shaped envelope one hundred and twenty feet long and fifty feet in diameter. Beneath this was a rudder placed in the same position as that of a ship; and suspended still further below was a large car fitted with a two-bladed screw-propeller, thirty feet in diameter. Manual labor was to be used for turning this screw, two relays of four men each relieving each other at the work. An ascent was made in February, 1872, with fourteen persons in the car, who, by working in relays, demonstrated that a speed of about seven miles an hour could be maintained in any direction in still air. As the wind was blowing about thirty miles an hour at the time, however, the course of the balloon could only be deflected, and the main object of the ascent—the return to Paris—could not be accomplished. In short, De Lome's balloon demonstrated little more than had been accomplished by Giffard with his steam-driven balloon. Both had shown that with sufficient power the balloon could be made to travel in any direction in still air, but neither had been able to make headway against a strong wind.

It was estimated at the time of Dupuy de Lome's ascent, that had a steam-engine of a weight corresponding to that of the eight workmen been used, at least twice the power could have been obtained. But steam was considered too dangerous, and some other motive power which combined lightness with power seemed absolutely essential. The electric motor gave promise of success in this direction, and in 1883 the two Tissandier brothers in France applied such a motor to a balloon that was able to make headway against a seven-mile breeze, but was still far from fulfilling the requirements of an entirely dirigible balloon. Two years later the motor-driven balloon La France, of Renard and Krebs, attained a speed of fourteen miles an hour, and showed a distinct advance over all preceding models.

Meanwhile motors were being reduced in weight and increased in power, and the hearts of aviators and balloonists were cheered by the fact that the light metal, aluminum, was steadily growing cheaper. Visions of an all-aluminum balloon were constantly before the minds of the inventors, and in 1894 such dreams took practical form in a balloon whose construction was begun by Herr Schwartz, under the auspices of the German Government. This balloon was of most complicated construction, depending for its lifting power upon the gas-filled aluminum tank, but utilizing for its steering-gear many of the features of the aeroplane. It was essentially a balloon, not a flying-machine, however, with a ten to twelve horse-power benzine-engine actuating four propelling screws.

TWO FAMOUS FRENCH WAR BALLOONS.

The lower figure the dirigible war balloon "La Patrie," which manœuvered on the Eastern boundary of France, and which was blown away and lost taking a northwesterly direction which probably landed it ultimately in the Arctic Sea—in 1908. The upper figure represents M. Deutsch's dirigible balloon "Ville de Paris" which was sent to the frontier to take the place of the lost "Patrie."

Before the balloon was completed Herr Schwartz died, but his plans were known to his wife, and, although considerably altered, were carried to completion. When all was finished, Herr Jaegels, an engineer who had had no experience as an aeronaut, volunteered to make an ascent and this metal ship-of-promise was launched. At first it rose rapidly and appeared to be making good progress against a strong wind; but suddenly it stopped, descended rapidly, and was smashed to pieces, the aeronaut saving himself by jumping just before it touched the ground. It developed later that he had lost control of the machine, simply because the machinery was too complicated for a single operator to handle. On discovering this, Herr Jaegels, confused for the moment, threw open the valve, causing the balloon to descend too rapidly. Thus the fruit of years of study and labor and the expenditure of fifty thousand dollars in money resulted in only about six minutes of actual flight.

To most persons this experiment of the aluminum balloon would seem to have been a dismal failure, but it was not so regarded by the advocates of the dirigible balloon. The flight of the balloon, to be sure, was far from a success; but this was attributed to improper management rather than to any inherent defect in the balloon itself, or in the principle upon which it was constructed. Instead of being discouraged, therefore, the school of balloonists, who had lost some of their prestige of late by the performances of the flying-machines of Maxim and Langley, undertook, through their enthusiastic representative, Count Zeppelin, the construction of the largest, most expensive, and most carefully built dirigible balloon heretofore constructed. This balloon was of proportions warranting the name of "air-ship." The great cigar-shaped body was almost four hundred feet in length, and thirty feet in diameter—the proportions of a fair-sized ocean liner—and like the hull of its ocean prototype, was divided into compartments—seventeen in number, and gas-tight. Its frame-work was of aluminum rods and wires, and the skin of the envelope was made of silk, coated with india-rubber. It was equipped with four aluminum screws, and two aluminum cars were placed below the body at a considerable distance apart. The motive power was supplied by benzine motors, selected because of their lightness.

The company for constructing this balloon was capitalized at about two hundred thousand dollars, the cost of the shed alone, which rested on ninety-five pontoons on the surface of the lake of Constance, near the town of Manzell, being fifty thousand dollars. July 2nd, 1910, the count and four assistants in the cars, started on the maiden voyage. The balloon rose and made headway at the rate of eighteen miles an hour, responding readily to the rudder, but soon broke or deranged some of the steering-gear so that it became unmanageable and descended at Immerstaad, a little over three miles from the starting-point. Considering the amount of thought, care, and money that had been expended upon it, its performance could hardly be looked upon as a startling success. By the advocates of the aeroplane principle it was considered an utter failure.

THE ZEPPELIN DIRIGIBLE BALLOON.

Count Zeppelin's famous balloons are of the semi-rigid type, being cased in thin loops of aluminum. The wing-like projections at the sides add greatly to the stability and dirigibility of the balloon. The problem of housing has been met by erecting a structure over the water. It is planned to have a balloon house that will revolve and thus facilitate the introduction of the balloon whatever the direction of the wind. With the above stationary house this is a difficult manœuvre if the wind chances to blow laterally.

But while Count Zeppelin was experimenting with his ponderous leviathan air-ship, a kindred spirit, the young Brazilian, M. Santos-Dumont, was making experiments along similar lines, but with balloons that were mere cockle-shells as compared with the German monster. The young inventor had come to Paris from his home in South America backed by an immense fortune, and by a fund of enthusiasm, courage, and determination unsurpassed by any aerial experimenter in any age. He began at once experimenting with balloons of different shapes, with screws and paddles, and, perhaps most important of all, with the new, light petroleum-motors just then being introduced for use on automobiles, electricity not having proved a success in aerial experiments.

His first balloon, No. 1, built in 1898, was devoid of any particularly novel features. His No. 2 showed some advancement, and his No. 3, while a decided improvement, still came far short of answering the requirements of a dirigible balloon. But the young experimenter was learning and profiting by his failures—and, incidentally, was having hairbreadth escapes from death, meeting with many accidents, and being severely injured on occasion.

About this time a prize of one hundred thousand francs was offered by M. Deutsch to the aeronaut who should ascend from a specified place in a park in Paris, make the circuit of the Eiffel Tower, and return to the starting-point within half an hour. With the honor of capturing this prize as an additional incentive, Santos-Dumont began the construction of his fourth balloon, the Santos-Dumont No. 4. In this balloon everything but bare essentials was sacrificed to lightness, even the car being done away with, the aeronaut controlling the machinery and directing the movements of the balloon from a bamboo saddle. But an accident soon destroyed this balloon, and a fifth was hastily constructed. With this the enthusiastic aeronaut showed that he was almost within grasping distance of the prize in a series of sensational flights between the first part of July and the first week in August. The tower was actually rounded, but on the return trip the balloon collided with a high building in the Rue Alboni and was wrecked, the escape of the aeronaut without a scratch being little short of miraculous.

Nothing daunted, the inventor began the construction of Santos-Dumont No. 6 immediately, finishing it just twenty-eight days after the construction of No. 5. A peculiarity of this balloon was that it was barely self-sustaining except when forced through the air by the propeller. The long cigar-shaped gas-bag was relatively small, and was filled to its limit of capacity with gas, while the lifting power was counterbalanced by the operator, car, engine, and ballast, so that the entire structure weighed practically the same as the air it displaced. At the stern was a powerful propeller. Obviously, then, if the long spindle-shaped machine was tilted upward at the forward end, and the propeller started, it would be driven upward; while if the forward end was lowered the propeller would drive it downward. If it was balanced so as to be perfectly horizontal, it would be forced forward in a horizontal direction. Deflections to right and to left were obtained by the ordinary type of vertical rudder; and thus any direction could be taken.

AN ENGLISH DIRIGIBLE BALLOON.

The photograph here reproduced gives a very vivid impression of the cumbersome nature of balloons of this modern type, and suggests the difficulties to be met in housing them safely when not in use.

To obtain the desired angle of inclination, Santos-Dumont made use of a sliding weight, and with this he guided his balloon upward and downward by shifting its position. Thus, although this balloon was a veritable balloon rather than a "flying-machine" proper, it really lacked the one essential common to balloons: it would not rise until propelled by mechanical means. It lacked the requisite of the flying-machine, however, in that it was not "many times heavier than the air." After giving this new balloon several preliminary trials, which included such exciting incidents as collisions with a tree in the Bois du Boulogne, an official attempt was made on October 29th, 1800. Above the heads of the gaping thousands, who, to a man, wished the daring navigator success, the balloon rounded the tower, and in twenty-nine minutes and thirty seconds from the moment of starting—thirty seconds less than the prescribed time-limit—the trip was successfully terminated.

This voyage must be considered as marking an epoch in aerial navigation. The dirigible balloon was accomplished. A decided step forward in the conquest of the air had been made, although from a practical standpoint this step was confessedly a short one. For while No. 6 could be propelled in any direction under ordinary conditions, carrying a single passenger, it was on the whole more of a toy ship than a practical sailing-craft. Nevertheless, its performance was a decided victory for the balloon over the flying-machine. No flying-machine of whatever type had ever even approached the performance of Santos-Dumont No. 6, which had carried a man on a voyage in the air, traveling with the wind, against it, and with the wind on either quarter at every possible angle at various times during the journey. And yet there were few scientists, indeed, if any, who considered that the problem of aerial navigation was solved; and to a large number Santos-Dumont's performance seemed little more than an extension of Giffard's idea, made possible by improved machinery not available half a century ago. To them it was the triumph of the energy, skill, and courage of an individual, not the triumph of a principle—which, after all, is the absolute essential.

ENGLISH (LOWER FIGURE) AND AMERICAN DIRIGIBLE WAR BALLOONS AND A WRIGHT AEROPLANE.

The above figures are introduced on one page for the purpose of comparison and contrast. The American balloon is the Baldwin airship. The essential clumsiness of a lighter-than-air craft, as contrasted with the relative gracefulness and manageableness of the aeroplane, is strikingly suggested by this illustration.

Since the successful performance of Santos-Dumont in rounding the Eiffel Tower many other dirigible balloons have been constructed, not only in America and in Europe by various inventors, but by the Brazilian aeronaut himself. The most remarkable of these is the Zeppelin II, the fifth creation of the indomitable Count Zeppelin. In principle and general lines of construction this balloon closely resembles the one described a few pages back. Its best performance, however, is more remarkable. Starting from Lake Constance on the night of May 29th, 1909, and sailing almost directly northward regardless of air currents, the balloon reached Bitterfield, a few miles beyond Leipzig, four hundred and sixty-five miles from the starting-point, the following evening. Turning back at this point, without alighting, it had almost completed its return trip, when on coming to the ground for a supply of fuel it was injured by collision with the branches of a tree. The injury sustained, while delaying and marring the voyage, did not prevent the balloon from completing its eight-hundred-and-fifty mile voyage, and establishing a new record for dirigibles.

This and sundry other flights amply demonstrated the dirigibility and relative safety of the balloon under varying atmospheric conditions. But the difficulties that attend the management of such a craft when not high in air were again vividly illustrated when, in April, 1910, the Zeppelin II., was totally wrecked while at anchor by the force of a gale which it might easily have outridden had it been beyond the reach of terrestrial obstacles.