So far in our story we have traced the origin and progress of the balloon, showing how from small beginnings it has grown to be an important invention, of great use to the scientific observer, the soldier, and the explorer, and the means of teaching us much fresh knowledge.

But in spite of the high hopes of early aeronauts, and the extravagant prophecies made when the first balloons ascended into the sky, it has long been evident that the balloon alone has not solved the problem of human flight or accomplished the conquest of the air. An ordinary balloon is, in fact, nothing more than a mere lifting machine, no more capable of sailing the sky, in the proper sense of the word, than a cork floating in the water is capable of sailing the sea. It has no movement of its own, but drifts simply at the mercy of the wind, and quite beyond control. By the discharge of ballast, or by the letting out of gas, the aeronaut can indeed cause it to rise or sink at pleasure, and sometimes when two currents of air are blowing aloft in different directions at the same time he may, by passing from one to the other, “tack” his balloon to some extent across the sky. Otherwise he has no power of guiding or directing it in the least degree, and should he lose sight of the earth above the clouds, has even no method of telling in which direction he is travelling.

Early inventors thought they would be able to steer balloons by means of sails, like a boat, but they soon found that this was impossible. The effect of hoisting a sail at the side of a balloon was merely to swing the balloon round until the sail was in front, while meantime it continued its course unaltered. The use of a rudder and other means were also tried, but without success; nor can such methods ever hope to succeed so long as a balloon floats in the air at the same pace as the wind that carries it forward. A balloon travelling with the wind may be compared to a boat drifting idly with the tide. As long as she drifts she refuses to answer her rudder, which swings idly. But presently the boatman hoists a sail, and the wind carries the boat onwards faster than the tide, and then immediately the rudder comes into action. Or should there be no wind, he may accomplish the same thing by dragging an anchor or other weight in the water, and so slowing his boat down until it moves slower than the current; he will then again find that his boat will answer her helm.

To steer his course in a balloon, therefore, the aeronaut must so arrange that he is travelling faster or slower than the wind in which he finds himself. To travel faster, he must employ some sort of engine or motor to drive his craft onwards. To travel slower, he must trail something along the ground beneath to act as a drag.

Part of the equipment of every balloon is a long trail-rope, which, when the balloon is aloft, hangs some 300 feet below the car. The object of this rope is to break the force of the fall when the balloon comes down to the earth at the end of the voyage. In the greater number of cases a balloon, in its final swoop to the ground, falls the last few hundred feet with considerable, and often uncomfortable, speed. But when provided with a trail-rope, as it descends more and more of the heavy rope will lie along the ground, and so lighten the weight of the balloon, and lessen the shock of falling.

If then a trail-rope were used of such length that it would sweep along the ground while the balloon was flying in the air, the effect would be to put a drag or brake on the balloon, and so render it capable of being steered to some extent with a sail; and this is what has actually been done in all attempts of the kind. But since a long rope dragging rapidly across the country is a very dangerous object, capable of doing great damage, and also liable to catch in trees and other obstacles, such experiments can only be tried with safety over the sea, or, as in the case of AndrÉe’s voyage, over desert or uninhabited country.

The best way of steering a balloon, therefore, is to provide it with some mechanical power which shall urge it onwards at a greater speed than the wind; and when this is done, it has ceased to be a balloon in the popular sense of the word, and has become an “airship.”

There is a great deal of confusion between the terms “airship,” and “flying machine,” and the two words are often considered as meaning the same thing. But while, strictly speaking, neither word in itself has any very definite meaning, it is gradually becoming more general to apply them to two widely different objects. According to this plan, although both names stand for an aerial vessel capable of travelling in the sky by its own motion, an airship is a machine supported in the air by reason of its buoyancy, while a flying machine is kept aloft only by virtue of its onward movement.

In other words, part of the construction of an airship consists of a bag or balloon, filled with gas or hot air, which causes the whole to rise and maintain its position in the air. This balloon part is quite independent of the machinery which drives the airship forward, and indeed if the engine ceases working, the vessel becomes nothing more than an ordinary balloon in its nature, and will behave like one. An airship, therefore, is in principle an apparatus lighter than air.

A flying machine, on the contrary, is heavier than air, and maintains its position aloft merely by the power it obtains from its engines, assisted by its special construction. The inventors of flying machines take as their analogy the flight of birds. Birds are creatures heavier than air, which yet manage to rise and fly by reason of the strength and construction of their wings. In the same way the heavy flying machine essays to fly by the power of its machinery. And, as a bird aloft, if its wings became disabled, would instantly drop towards earth, so a flying machine would immediately commence to fall if its engine stopped or ceased to move with sufficient power. The airship and the flying machine, therefore, may be regarded as rival aerial vessels, and their inventors and advocates, sometimes known as “lighter-than-air-ites” and “heavier-than-air-ites,” though both working for the same end, are endeavouring to accomplish their aim by widely different methods.

Up to the present day the airship—to which we will first turn our attention—has been much more largely and successfully experimented with than the flying machine. It is, however, the opinion of many, including the great authority Sir Hiram Maxim, that in the future the flying machine will become the more important invention of the two. “In all Nature,” says Sir Hiram, “we do not find a single balloon. All Nature’s flying machines are heavier than air.” And from this he argues that, as Nature is ever our best guide and example, a flying machine heavier than air will be in the end most likely to succeed.

One of the earliest airships which achieved any success was invented by a Frenchman, M. Giffard, about the year 1852. He made his balloon of an elongated or cigar shape, a form adopted by airship inventors as offering less resistance to the air than the ordinary globular or pear shape. To this balloon, which was 104 feet long and 39 feet in diameter, he attached a steam-engine of three-horse power, weighing 462 lbs. and working a screw-propeller, which, by its rapid revolutions, urged the balloon onwards through the air, even as the screw of a steamship urges the vessel through the water. With this apparatus he succeeded on one occasion, for a very short while, in obtaining a speed of six and a half miles an hour. Twenty years later another Frenchman, M. Dupuy de LÔme, constructed another airship; but fearing to place an engine so near the gas of his balloon, he used the strength of eight men to work his screw. This was a very wasteful mode of supplying energy, for the weight of the men was very great in proportion to their strength, and this machine, during its trial, did not attain as great a speed as Giffard’s. Twelve years after a third Frenchman, M. Tissandier, took up the same experiments. His elongated balloon was smaller than the two previous, and his engine was an electric motor of one and a half horse-power. On one occasion a speed of nearly eight miles an hour was attained.

By this time the French Government had become interested in the work, and provided money to continue investigations. The result of this was that in 1885 two officers of the French army, Captains Renard and Krebs, brought out by far the most successful airship yet constructed. It was 165 feet long, 27 feet in diameter, and was driven by an electric motor of nine horse-power. That this machine proved itself perfectly capable of being guided in the air is amply shown by the fact that it returned to its shed five times out of the seven on which it was publicly taken out. It also attained a speed of fourteen miles an hour, and indeed it would seem that Renard and Krebs, although their names are now almost forgotten, accomplished nearly as great things twenty years ago as the popular airship inventors of the present day.

One of the greatest difficulties with which early inventors had to contend was the enormous weight of their engines. The machinery they were obliged to use to drive their airships through the air weighed more than their balloons, unless made of unwieldy size, had power to lift. The same difficulty indeed exists at the present time, though to a much less degree. Of late years, and especially since the introduction of the motor-car, great progress has been made in the construction of light but powerful engines, or motors, and the employment of petrol vapour instead of coal or oil has very greatly lessened the weight of the fuel which has to be carried.

In consequence of this improvement many airships have recently been made which have met with varying success, and many more are at the present moment in process of construction. Among the host of inventors, whose names it would here be impossible even to mention, three stand out from the rest in special prominence—Zeppelin, Santos Dumont, and Stanley Spencer—all three the inventors of airships which have, by actual experience, proved their power of steering a course across the sky.

Of these rival airships, by far the largest and most elaborate was that built by the first named, Count Zeppelin, a distinguished veteran soldier of the German army. For many years he had spent his time and fortune in making experiments in aerial navigation, and at length in 1900, having formed a company and collected a large sum of money for the purpose, he produced an enormous airship, which, from its size, has been compared to a man-of-war. In shape Count Zeppelin’s invention resembled a gigantic cigar, 420 feet in length, pointed at both ends. The framework was made of the specially light metal aluminium, covered over with silk, and though from outside it looked all in one piece, within it was divided into seventeen compartments, each holding a separate balloon made of oiled silk and absolutely gas-tight. The object of this was to prevent the tendency the gas has to collect all at one end as the ship forces its way through the air. These balloons were filled with pure hydrogen, the cost of the inflation alone being £500. Beneath was slung a long gangway, 346 feet in length, with two cars, also made of aluminium, attached to it. In these cars were placed two motor-engines of sixteen horse power each, driven by benzine, and working a pair of screw-propellers attached to the balloon. A steering apparatus was placed at each end, and the whole machine, with five passengers, weighed about eleven tons.

To lessen the effects of a possible fall, the experiments were carried out over water, and the great airship was housed in a shed built on Lake Constance. The cost of this shed alone was enormous, for it was elaborately constructed on pontoons, and anchored in such a way that it could be turned round to allow the airship to be liberated from it in the best direction to suit the wind. The trial trip was made one evening in June 1900, when a very light wind was blowing. The great machine rose into the air, carrying Zeppelin and four companions to a height of 800 feet. The steering apparatus then being put into action, it circled round and faced the wind, remained stationary for a short while, and then sank gracefully and gently upon the water. A few days later another and more successful trial was made. The wind at the time was blowing at sixteen miles an hour, but in spite of this the airship slowly steered its course against the wind for three and a half miles, when, one of the rudders breaking, it was obliged to come down. On one or two other occasions also it made successful voyages, proving itself to be perfectly manageable and capable of being steered on an absolutely calm day. The expense of the experiments was, however, tremendous; money fell short, and the great machine, the result of many years’ labour and thought, has since been abandoned and broken up.

A far happier fate has so far attended the efforts of the brave young Brazilian, Albert Santos Dumont. The wealthy son of a successful coffee-planter, he had always from his boyhood been keenly interested in aeronautics, and, coming to Paris, he constructed in 1898 an airship of a somewhat novel kind. His balloon was cigar-shaped, 83 feet long, and holding 6500 feet of pure hydrogen. Attached to the balloon, and working a propeller, was a small motor like those used for motor cycles, and astride of this Santos Dumont rode, bicycle fashion, steering his course with a rudder. In this ingenious machine he ascended from the Botanical Gardens in Paris and circled several times round the large captive balloon then moored there, after which he made a number of bold sweeps in the air, until an accident occurred to his engine and he came precipitately to the ground. Though shaken he was by no means discouraged, and declared his intention of continuing his experiments until he should have invented an airship which, in his own words, should be “not a mere plaything, but a practical invention, capable of being applied in a thoroughly useful fashion.”

Accordingly he constructed one machine after another, gaining fresh knowledge by each new experience, and profiting by the accidents and failures which continually beset him in his dangerous and daring work. Before long also he received an additional incentive to his labours. Early in the year of 1900 it was announced by the Paris Aero Club, a society of Frenchmen interested in aeronautical matters, that one of its members, M. Deutsch, had offered a prize of 100,000 francs—about £4000—to the man who, starting from the Aero Club grounds at Longchamps in a balloon or flying machine, should steer his course right round the Eiffel Tower and back to the starting-place—a distance of three and a half miles—within half an hour. If the prize were not won within a certain time, his offer was to be withdrawn, and meanwhile he promised a certain sum of money every year for the encouragement of aeronautical experiments. The offer of this reward set many inventors to work upon the construction of various aerial vessels of all kinds, but from the beginning Santos Dumont was well to the fore. By the middle of 1901 he had completed what was his sixth airship—a cigar-shaped balloon, 100 feet long, its propeller worked by a motor-car engine of fifteen horse-power—and with it, on July 15th, he made a splendid attempt for the prize. Starting from the Club grounds, he reached the Eiffel Tower in thirteen minutes, and, circling round it, started back on his homeward journey. But this time his voyage was against the wind, which was really too strong for the success of his experiment; part of his engine broke down, and the balance of the vessel became upset; and although he managed to fight his way back to the starting point, he arrived eleven minutes behind time, and so failed to fulfil M. Deutsch’s conditions.

Again, on the 9th of August, having in the meantime made further trials with his machine, he embarked on another attempt to carry off the prize. He chose the early hours of the morning, starting shortly after six from the Club grounds, where only a few friends, among them the keenly interested M. Deutsch, were present. The day was apparently perfect, and when, after the lapse of five minutes only, he had reached the Tower and swung gracefully round it, every one was convinced that this time the prize was certain to be won. But the homeward journey was all against the wind, which was blowing more powerfully aloft than on the ground, and suddenly the onlookers were horrified to see the fore part of the balloon double right back. By so doing the silken envelope became torn and the gas began escaping. Rapidly the balloon appeared to wither up and shrink together. The engine was seen still to be working, though no progress was now being made. Then the whole apparatus collapsed utterly, and fell with sickening speed upon the house-tops.

Deutsch and his companions watched the fall horror-struck, and jumping into their motorcars hurried to the spot, convinced that a fatal accident must have occurred. But they found that, although the airship was smashed to pieces, its plucky inventor had almost miraculously escaped unhurt. The wrecked machine had fallen upon the roof of a house in such a way that the keel had caught upon a corner, and the car, which was fastened to it, hung at a perilous angle down the side of a wall. Fortunately Dumont was secured to his car by a leather belt, and he managed to hold on, though in considerable danger lest the keel should break and let him fall, until rescued by a fireman with a rope. His machine was hopelessly ruined; but when asked what he intended to do next he merely answered: “Begin again. Only a little patience is necessary.” A new machine, “Santos Dumont VII.,” was ready in less than a month, and tested on the 6th of September. It behaved beautifully, and all went well until the trail-rope caught in a tree. In liberating it the framework became bent, and the airship was being towed back to its shed when a sudden gust of wind tore it away from those who held it. It immediately rose into the air, and on Dumont opening the valve the whole collapsed and fell to earth with a great shock. Again the lucky inventor escaped unhurt, though owning this time that he had “felt really frightened.” Ten days later, in another trial, the airship came in contact with some trees, which pierced the silk and let out the gas, so that it fell precipitately twenty feet. But the aeronaut appeared to bear a charmed life, for once more he was none the worse for the fall. Several other unsuccessful trials followed, and then, on the 19th of October, Santos Dumont made another grand attempt for the prize.

Starting with the wind in his favour, his machine travelled at the rate of thirty miles an hour, and rounded the Eiffel Tower in nine minutes. But in the journey homewards the airship had to struggle with a wind blowing at thirteen miles an hour. In endeavouring to “tack” the machinery became upset, and Dumont, leaving his car, crawled along the framework to the motor, which he succeeded in putting in order again. But this naturally occasioned some delay, and though he accomplished the rest of his journey in eight minutes, the Committee at first decided he had exceeded the allotted time by forty seconds, and so had lost the prize. Great popular indignation was excited by this decision, for public sympathy was all with the daring and persistent young Brazilian, and M. Deutsch himself was most anxious he should receive the award. Finally, he was considered to have fairly won it, and the money, which he afterwards divided among the poor, was formally presented to him.

Early in the next year Santos Dumont continued his experiments at Monaco, and on one occasion came down in the sea, and had to be rescued in the Prince of Monaco’s own steam yacht. After this there was a talk of further voyages being made in England, but the project came to nothing, and although Dumont made other ascents in Paris in the summer of 1903, he does not appear to have eclipsed his previous record.

But although Santos Dumont came through all his accidents and perils so happily, his example led to terrible disaster on the part of a luckless imitator. In 1902 M. Severo, also a Brazilian, was fired with a desire to share his fellow-countryman’s fame, and he also constructed an airship with which he proposed to do great things. But while Dumont was a skilled aeronaut of large experience, as well as a mechanician, Severo knew scarcely anything about the subject, and had only been aloft once or twice. Proof of his ignorance is shown by the fact that his motor-engine was placed only a few feet away from the valve through which the gas from the balloon would escape.

The ascent took place in Paris early in the morning of the 12th of May, and was witnessed, unhappily, by Severo’s wife and son. Bidding them good-bye, he stepped into the car, and, accompanied by an assistant, rose above the town. The balloon rose steadily, and appeared to steer well. Then Severo commenced to throw out ballast, and when the airship had risen 2000 feet it was suddenly seen to burst into a sheet of flame. A terrible explosion followed, and then the whole fell to the ground a hopeless wreck, and the two men were dashed to pieces in the fall. It is believed that this dreadful disaster, which recalls the fate of PilÂtre de Rozier, was caused by the hydrogen gas, which escaped from the valve during the rapid rise, becoming ignited by the engine, which, as has been said, was placed dangerously close.

Nor was this, unhappily, the only accident of the kind in Paris during the year. Only five months later, on the 13th of October, Baron Bradsky ascended with an assistant in a large airship of his own invention. Through faulty construction, the steel wires which fastened the car to the balloon broke, the two became separated, the car fell, and its occupants were killed on the spot.

So far, the credit of the only English airship which has yet flown rests with Mr. Stanley Spencer, the well-known aeronaut. Mr. Spencer comes of a race of aeronauts. His grandfather, Edward Spencer, was the great friend and colleague of Charles Green, and shared with him some of his chief ballooning adventures, notably the terrible voyage when Cocking lost his life. Green stood godfather to Edward Spencer’s son, who was christened Charles Green after him. He also grew up to be an aeronaut, and made several inventions and improvements relating to balloons and flying machines. His love of ballooning, inherited from his father, has been passed on to his children, and his three eldest sons, Percival, Arthur, and Stanley, are chief among British aeronauts, and indeed have practically the monopoly of professional ballooning and balloon manufacture in Great Britain. Nor have they confined themselves to this country. All three have taken their balloons and parachutes to distant parts of the world, and among their many hundreds of ascents, both abroad and at home, have met with all manner of exciting and perilous adventures, though never yet with serious mishap. Their knowledge of practical aeronautics, then, is unrivalled, and Mr. Stanley Spencer had the experience of three generations to guide him when, in 1902, he set to work to build an airship which he had long been devising.

His first machine was a comparatively small one, capable only of lifting a light man. It took the usual form of a cigar-shaped balloon, the framework of which was built of bamboo, driven forward by a screw-propeller worked by a small petrol engine. Warned by the fate of the unfortunate Severo, Mr. Spencer placed his engine far away from the valve. Profiting also by Santos Dumont’s experience, he constructed his balloon in such a manner that, should it become torn and the gas escape, the empty silk would collapse into the form of a parachute and break the fall. Furthermore, there was an arrangement by which, while aloft, ordinary air could be forced into the balloon to replace any loss of gas, and so keep the silk always fully inflated and “taut”—a very important factor in a machine that has to be driven forward through the atmosphere.

With this airship Mr. Spencer, as also his equally daring wife, made several highly successful trials at the Crystal Palace, when it was found to steer well and answer its helm most satisfactorily. Mr. Spencer also made two long voyages, from London and from Blackpool, on both of which occasions he found he could manoeuvre his airship with considerable success, make circular flights, and sail against the wind, provided it was blowing only at moderate speed.

Encouraged by his success, he next built a similar but much larger machine, nearly a hundred feet long, holding 30,000 cubic feet of gas, and driven by a petrol motor of twenty-four horse-power. In this case the propeller, instead of being placed at the rear, as in general, is at the front of the airship, thereby pulling it forward through the air instead of pushing it from behind. By this arrangement Mr. Spencer thinks his balloon would have less tendency to double up when urged against a strong wind. The steering is done by a rudder sail at the stern, and to cause his machine to sail higher or lower, the aeronaut points its head up or down by means of a heavy balance-rope.

This new airship was ready by the summer of 1903, but the unfavourable weather of that stormy season again and again interfered with the experiments. On the 17th of September Mr. Spencer announced his intention of sailing from the Crystal Palace round the dome of St. Paul’s, and returning to his starting-place. The Cathedral was indeed safely reached, but the increasing breeze, now blowing half a gale, baffled all his attempts to circle round. Again and again, till his hands were cut and bleeding with the strain of the ropes, he brought his machine up, quivering, to the wind, but all to no purpose, until at length, abandoning the attempt, he sailed with the current to Barnet. More favourable results may doubtless be looked for with better weather conditions.

In France during 1903 the brothers Lebaudy made some successful trips with an airship of their own construction. Many other airships are now being built in all parts of the world, in preparation for the aeronautical competitions to take place in America on the occasion of the St. Louis Exhibition of this year.