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valve easily accomplish his descent, particularly if friendly helping hands are near. But his anchor may not catch, or may give way, and a strong wind may carry him on. His task is then a difficult one, requiring great nerve and presence of mind. He may see a building or a tree in his way, towards which he is being hurled with fatal force, when his only chance of salvation is instantly to throw out ballast to rise and escape it; after which he must renew his attempt. The swaying of the balloon by the wind when the grapnel has caught, the highly inclined position, requiring him to hold on to avoid being thrown out, the risk of dragging, and many other contingencies, make a descent in a high wind a thing only to be undertaken by very experienced hands.
In some cases balloons, after being inflated, are allowed only to rise a certain height under restraint, being secured to the earth by long cords. These are called captive balloons. They have at different periods been fashionable, as affording amusement to the public, and, in some cases, have been of real utility. Two large captive balloons have been made of late years, one at Paris, in 1867, the other in London, in 1868. The Paris one was placed in a building adjoining the Exhibition, and it carried twelve persons in the car to a height of about 800 feet. The London captive balloon, installed in Ashburnham Park, Chelsea, was much larger, 93 feet diameter, and containing about 425,000 cubic feet. It was filled with hydrogen gas, and took up thirtytwo people at a time to a height of 2000 feet; a steam-engine of 200 horse-power being used to draw it down again. Both these fine balloons were made by M. Henri Giffard, of whom we shall have more to say by-and-by.
It may now be asked of what use are balloons? Almost all writers on the subject have concurred in lamenting that an invention of such high promise should have performed so little. The balloon has been a singular exception to the ordinary course of mechanical discoveries. The steam-engine, machinery, steam navigation, railways, the electric telegraph, photography, iron construction, have all, soon after their introduction, received rapid development; while this art of aerial locomotion, from which so much was expected, has remained just where it was in 1783. Franklin's child has never grown; he is an infant still. The balloon, instead of revolutionising the world, has settled down to the position of a huge toy, and has taken rank with fireworks and monster bands as an attraction to fêtes and holiday amusements, for the mere gratification of idle curiosity. There have been, however, two purposes of special character
to which the balloon has been seriously applied, and in which it has rendered good service, namely, the scientific investigation of atmospheric phenomena, and the art of war.
From the time of
First, as to the scientific use of balloons. their invention philosophers have thought them applicable to aerial and meteorological researches, and many ascents have been planned at different times with this view. At the beginning of the present century an aeronaut named Robertson, who is spoken highly of by Arago, made such ascents at Hamburg and St. Petersburg, and about the same date Gay-Lussac and Biot undertook similar experiments at Paris, at the suggestion of Laplace. Messrs. Barral and Bixio, in 1850, and Mr. Welch, of Kew, in 1852, followed in the same track; but the most extensive series of investigations of the kind have been made within the last ten years, at the instance of the British Association, by Mr. Glaisher, of the Greenwich Observatory. He associated himself with our most experienced living aeronaut, Mr. Coxwell, and the ascents were made in a large balloon of 90,000 cubic feet capacity, constructed specially for the purpose. The objects were to make observations at high altitudes on the thermometric, hygrometric, electrical, and chemical condition of the air; on the magnetic force; on the spectrum and solar influences; on clouds and vapours; on aerial currents; on sound; and on any other interesting phenomena that offered themselves. For Mr. Glaisher's results on these points we must refer to his very full official Reports; but he has given to the world a popular account of some of his voyages in the book mentioned on our first page. In the years 1862 to 1866 he made twenty-eight ascents, in one of which he rose to the great height of 37,000 feet, or seven miles. At this elevation he lost consciousness, and the cover of his book is ornamented with his picture as he hung over the edge of the car in this critical condition. The following extract, descriptive of 'The High Regions,' will give an idea of Mr. Glaisher's style :—
'Above the clouds the balloon occupies the centre of a vast hollow sphere, of which the lower portion is generally cut off by a horizontal plane. This section is in appearance a vast continent, often without intervals or breaks, and separating us completely from the earth. No isolated clouds hover above this plane. We seem to be citizens of the sky, separated from the earth by a barrier which seems impassable. We are free from all apprehension such as may exist when nothing separates us from the earth. We can suppose the laws of gravitation are for a time suspended, and in the upper world, to which we seem now to belong, the silence and quiet are so intense, that peace and calm seem to reign alone.
'Above our heads arises a noble roof-a vast dome of the deepest blue; in the east may perhaps be seen the tints of a rainbow on the point of vanishing; in the west the sun silvering the edges of broken clouds. Below these light vapours may rise a chain of mountains, the Alps of the sky, rearing themselves one above the other, mountain above mountain, till the highest peaks are coloured by the setting sun. Some of these compact masses look as if ravaged by avalanches, or rent by the irresistible movements of glaciers. Some clouds seem built up of quartz, or even diamonds; some, like immense cones, boldly rise upwards; others resemble pyramids whose sides are in rough outline. These scenes are so varied and so beautiful, that we feel that we could remain for ever to wander above these boundless planes. But we must quit these regions to approach the earth; our revolt against gravity has lasted long enough, we must now obey its laws again. As we descend, the summits of the silvery mountains approach us fast, and appear to ascend towards us; we are already entering deep valleys, which seem as if about to swallow us up, but mountains, valleys, and glaciers all flee upward. We enter the clouds and soon see the earth: we must make the descent, and in a few minutes the balloon lies helpless, and half empty, on the ground.'
In addition to Mr. Glaisher's accounts, the work also contains descriptions of balloon voyages by three eminent French aeronauts, Messrs. Flammarion, De Fonvielle, and Gaston Tissandier. M. Tissandier deserves credit for having introduced a new feature into balloon descriptions, by taking up his brother, a practised artist, who has illustrated the balloon adventures and the scenery of the voyages with much skill.*
The most recent scientific ascent was attended with a lamentable result. On the 15th April, 1875, M. Tissandier started from Paris, accompanied by M. Croce-Spinelli, an engineer, and M. Sivel, a naval officer, the object being to make certain observations at high altitudes. The records of the height do not show so great an elevation as that attained by Mr. Glaisher, but either from the effect of the rarefaction, or from the inhalation of gas, M. Tissandier's companions were both suffocated, and he himself narrowly escaped with his life. Is there enough to be learnt at these great elevations to justify the risk they entail?
The application of balloons to the art of war presents great interest, on account of the remarkable success with which they were used by the Parisians, in the late siege, to establish com
* We must give a decided preference to the French edition of the work, not only because there are important omissions in the English copy, but because the style of the French authors, who are all practised writers, and express themselves forcibly and often eloquently, suffers much in translation.
munication with the country in general, in defiance of a most vigorous blockade. We make no apology, therefore, for giving this part of our subject a more lengthy notice.
Soon after Montgolfier's and Charles's first trials the idea arose of using the aerostat, as the French have called it, for military purposes. At the siege of Condé, in 1793, an attempt was made to send news by a balloon across the investing lines; and about the same time, the celebrated Guyton de Morveau proposed to establish captive balloons as posts of observation in communication with the Republican armies. The idea was approved by the Committee of Public Safety, on the condition that sulphuric acid should not be used for the production of the hydrogen, all the sulphur obtainable being wanted for powder. Lavoisier got over the difficulty by his discovery of the decomposing action of red-hot iron on steam, and De Morveau's proposal was put in practice. A school of aerostatics was established at Meudon, and two companies of aérostiers were attached to the army. The campaign of the Sambre and Meuse was just then beginning, and and an energetic young officer of the balloon corps, named Coutelle, was sent in all haste with two balloons to its aid. The General, who had received no notice of the step, at first treated the young man as a lunatic, and threatened to shoot him; but he was soon convinced of the importance of the invention, and adopted it without further hesitation. At the siege of Maubeuge and the battle of Fleurus, Coutelle rendered most important services in obtaining information as to the position and movements of the enemy, who afterwards made honourable testimony to the skill and ingenuity of the proceeding.
After this, military aerostation seems to have died away. The first Napoleon took balloons into Egypt, but the English seized the filling apparatus: his nephew had one made for the Italian campaign, in 1859, and appointed Garnerin as his aeronaut; but it only arrived the day after Solferino. We also hear of successful aerostation in the American Civil War a few years later, the signals being communicated to the earth by telegraph wires. At the breaking out of the Franco-German War in July 1870, there were in Paris many experienced aeronauts, including Tissandier, De Fonvielle, Nadar, Jules Duruof, and Eugène Godard, the latter of whom had made 800 ascents. The subject of military ballooning was mooted, and received some faint support from the Imperial Government; but before anything of use could be arranged the disaster of Sedan occurred, and was followed in a few days by the close investment of the Capital. The new Government at once addressed themselves to the aeronauts, with
the view of opening aerial communications with the exterior. Six balloons were found, all in indifferent condition, the worst being the Solferino one, 'L'Impérial,' which, M. Tissandier is careful to tell us, 'on n'a jamais su réparer.' The first ascent was made by M. Duruof, on the 23rd September; he carried a large number of despatches, and landed safely in three hours near Evreux. He was followed on the 21st by M. Mangin; on the 29th, by Godard, jun.; and on the 30th by Gaston Tissandier, who has given an animated account of his voyage.
Encouraged by this success, the Government established the Balloon Post on a regular system, and took immediate steps for the manufacture of a large number of balloons, under specified conditions, and in the quickest possible time. It was easier, however, to make the vessels than to find captains for them, for experienced aeronauts were very few, and when they had once left Paris there was no returning. In this strait it was resolved to invite the help of sailors, a class of men whose training made them familiar with operations and dangers akin to those of ballooning. The appeal was well answered; many fine brave fellows offered themselves; they received such instruction as was possible, and a large number of ascents were conducted by them. Our topsail is high, Sir,' said a tar to his Admiral, who saw him ascend, and difficult to reef; but we can sail all the same, and, please God, we'll arrive.' The employment of some acrobats from the Hippodrome was less fortunate, as they made use of their skill, when in difficulty, to slip down the guide rope to the earth, leaving the passengers and despatches to take care of themselves.
The balloon service was on the whole conducted with remarkable success and precision. From September to January sixty-four balloons were sent off, and of these fifty-seven fulfilled their mission, the despatches reaching their destination. The total number of persons that left Paris was 155, the weight of despatches was 9 tons, and the number of letters, 3,000,000. The speed of transit varied usually from about 7 to 40 or 45 miles an hour. In four cases a speed above 50 miles was attained, and in one instance about 80 miles; the high speeds being all with south-westerly winds.
We may mention some of the voyages which offer special interest. Gambetta left by the Armand Barbès' (every balloon had a name) on the 7th of October; being too low, he was fired on by the Prussians, and narrowly escaped being hit. 27th of October, the Bretagne' fell, by some bad management, into the hands of the Prussians near Verdun; on the 4th of November, the Galilee' had a similar fate near Chartres; and