The Dominion of the Air Part 10

Only a small minority, amounting to about sixty out of 360 birds taken up, returned to Paris, but these are calculated to have conveyed among them some 100,000 messages. To reduce these pigeon messages to the smallest possible compa.s.s a method of reduction by photography was employed with much success. A long letter might, in this way, be faithfully recorded on a surface of thinnest photographic paper, not exceeding the dimensions of a postage stamp, and, when received, no more was necessary than to subject it to magnification, and then to transcribe it and send a fair copy to the addressee.

The third voyage from Paris, on September 29th was undertaken by Louis G.o.dard in two small balloons, united together, carrying both despatches and pigeons, and a safe landing was effected at Mantes This successful feat was rival led the next day by M. Tissandier, who ascended alone in a balloon of only some 26,000 cubic feet capacity and reached earth at Dreux, in Normandy.

These voyages exhausted the store of ready-made balloons, but by a week later the first of those being specially manufactured was ready, and conveyed in safety from the city no less a personage than M. Gambetta.

The courageous resolve of the great man caused much sensation in Paris, the more so because, owing to contrary winds, the departure had to be postponed from day to day. And when, at length, on October 7th, Gambetta and his secretary, with the aeronaut Trichet, actually got away, in company with another balloon, they were vigorously fired at with shot and sh.e.l.l before they had cleared St. Denis. Farther out over the German posts they were again under fire, and escaped by discharging ballast, not, however, before Gambetta had been grazed by a bullet. Yet once more they were a.s.sailed by German volleys before, about 3 p.m., they found a haven near Montdidier.

The usual dimensions of the new balloons gave a capacity of 70,000 cubic feet, and each of these, when inflated with coal gas, was calculated to convey a freight of pa.s.sengers, ballast, and despatches amounting to some 2,000 pounds. Their despatch became frequent, sometimes two in the same twenty-four hours. In less than a single week in October as many as four balloons had fallen in Belgium, and as many more elsewhere. Up till now some sixteen ventures had ended well, but presently there came trouble. On October 22nd MM. Iglesia and Jouvencel fell at Meaux, occupied by the Prussians; their despatches, however, were saved in a dung cart. The twenty-third voyage ended more unhappily. On this occasion a sailor acted as aeronaut, accompanied by an engineer, Etienne Antonin, and carrying nearly 1,000 pounds of letters. It chanced that they descended near Orleans on the very day when that town was re-occupied by the enemy, and both voyagers were made prisoners. The engineer, however, subsequently escaped. Three days later another sailor, also accompanied by an engineer, fell at the town of Ferrieres, then occupied by the Prussians, when both were made prisoners. In this case, also, the engineer succeeded in making his escape; while the despatches were rescued by a forester and forwarded in safety.

At about this date W. de Fonvielle, acting as aeronaut, and taking pa.s.sengers, made a successful escape, of which he has given a graphic account. He had been baulked by more than one serious contretemps. It had been determined that the departure should be by night, and November 19th being fixed upon, the balloon was in process of inflation under a gentle wind that threatened a travel towards Prussian soil, when, as the moment of departure approached, a large hole was accidentally made in the fabric by the end of the metal pipe, and it was then too late to effect repairs. The next and following days the weather was foul, and the departure was not effected till the 25th, when he sailed away over the familiar but desolated country. He and his companions were fired at, but only when they were well beyond range, and in less than two hours the party reached Louvain, beyond Brussels, some 180 English miles in a direct line from their starting point. This was the day after the "Ville d'Orleans" balloon had made the record voyage and distance of all the siege, falling in Norway, 600 miles north of Christiania, after a flight of fifteen hours.

At the end of November, when over thirty escape voyages had been made, two fatal disasters occurred. A sailor of the name of Prince ascended alone on a moonless night, and at dawn, away on the north coast of Scotland, some fishermen sighted a balloon in the sky dropping to the westward in the ocean. The only subsequent trace of this balloon was a bag of despatches picked up in the Channel. Curiously enough, two days later almost the same story was repeated. Two aeronauts, this time in charge of despatches and pigeons, were carried out to sea and never traced.

Undeterred by these disasters, a notable escape was now attempted. An important total eclipse of the sun was to occur in a track crossing southern Spain and Algeria on December 22nd. An enthusiastic astronomer, Janssen, was commissioned by the Academy of Sciences to attend and make observations of this eclipse. But M. Janssen was in Paris, as were also his instruments, and the eclipse track lay nearly a thousand miles away.

The one and only possible mode of fulfilling his commission was to try the off-chance afforded by balloon, and this chance he resorted to only twenty days before the eclipse was due.

Taking with him the essential parts of a reflecting telescope, and an active young sailor as a.s.sistant, he left Paris at 6 a.m. and rose at once to 3,600 feet, dipping again somewhat at sunrise (owing, as he supposed, to loss of heat through radiation), but subsequently ascending again rapidly under the increased alt.i.tude of the sun till his balloon attained its highest level of 7,200 feet. From this elevation, shortly after 11 a.m., he sighted the sea, when he commenced a descent which brought him to earth at the mouth of the Loire. It had been fast travelling--some 300 miles in little more than three hours--and the ground wind was strong. Nevertheless, neither pa.s.sengers nor instruments were injured, and M. Janssen was fully established by the day of eclipse on his observing ground at Oran, on the Algerian coast. It is distressing to add that the phenomenon was hidden by cloud. In the month that followed this splendid venture no fewer than fifteen balloons escaped from Paris, of which four fell into the hands of the enemy, although for greater security all ascents were now being made by night.

On January 13th, 1871, a new device for the return post was tried, and, in addition to pigeons, sheep dogs were taken up, with the idea of their being returned to the city with messages concealed within their collars.

There is apparently no record of any message having been returned to the town by this ingenious method. On January 24th a balloon, piloted by a sailor, and containing a large freight of letters, fell within the Prussian lines, but the patriotism of the country was strong enough to secure the despatches being saved and entrusted to the safe conveyance of the Post Office. Then followed the total loss of a balloon at sea; but this was destined to be the last, save one, that was to attempt the dangerous mission. The next day, January 28th, the last official balloon left the town, manned by a single sailor, carrying but a small weight of despatches, but ordering the s.h.i.+ps to proceed to Dieppe for the revictualling of Paris.

Five additional balloons at that time in readiness were never required for the risky service for which they were designed.

There can be little doubt that had the siege continued a more elaborate use of balloons would have been developed. Schemes were being mooted to attempt the vastly more difficult task of conveying balloons into Paris from outside. When hostilities terminated there were actually six balloons in readiness for this venture at Lisle, and waiting only for a northerly wind. M. de Fonvielle, possessed of both courage and experience, was prepared to put in practice a method of guiding by a small propelling force a balloon that was being carried by sufficiently favouring winds within a few degrees of its desired goal--and in the case of Paris the goal was an area of some twenty miles in diameter.

Within the invested area several attempts were actually made to control balloons by methods of steering. The names of Vert and Dupuy de Lome must here be specially mentioned. The former had elaborated an invention which received much a.s.sistance, and was subsequently exhibited at the Crystal Palace. The latter received a grant of L1,600 to perfect a complex machine, having within its gas envelope an air chamber, suggested by the swimming bladder of a fish, having also a sail helm and a propelling screw, to be operated by manual labour.

The relation of this invention to others of similar purpose will be further discussed later on. But an actual trial of a dirigible craft, the design of Admiral Labrousse, was made from the Orleans railway station on January 9th. This machine consisted of a balloon of about the standard capacity of the siege balloons, namely some 70,000 cubic feet, fitted with two screws of about 12 feet diameter, but capable of being readily worked at moderate speed. It was not a success. M. Richard, with three sailors, made a tentative ascent, and used their best endeavours to control their vessel, but practically without avail, and the machine presently coming to earth clumsily, a portion of the gear caught in the ground and the travellers were thrown over and roughly dragged for a long distance.

Fairly looked at, the aerial post of the siege of Paris must be regarded as an ambitious and, on the whole, successful enterprise. Some two million and a half of letters, amounting in weight to some ten tons, were conveyed through the four months, in addition to which at least an equal weight of other freight was taken up, exclusive of actual pa.s.sengers, of whom no fewer than two hundred were transported from the beleaguered city. Of these only one returned, seven or eight were drowned, twice this number were taken prisoners, and as many again more or less injured in descents. From a purely financial point of view the undertaking was no failure, as the cost, great as it necessarily became, was, it is said, fairly covered by the postage, which it was possible and by no means unreasonable to levy. The recognised tariff seems to have been 20 centimes for 4 grammes, or at the rate of not greatly more than a s.h.i.+lling per English ounce. Surely hardly on a par with fame in prices in a time of siege.

It has already been stated that the defenders of Paris did not derive substantial a.s.sistance from the services of such a reconnoitring balloon as is generally used in warfare at every available opportunity. It is possible that the peculiar circ.u.mstances of the investment of the town rendered such reconnaissance of comparatively small value. But, at any rate, it seems clear that due opportunity was not given to this strategic method. M. Giffard, who at the commencement of the siege was in Paris, and whose experience with a captive balloon was second to none, made early overtures to the Government, offering to build for L40,000 a suitable balloon, capable of raising forty persons to a height of 3,000 feet. Forty aerial scouts, it may be said, are hardly needed for purposes of outlook at one time; but it appears that this was not the consideration which stood in the way of M. Giffard's offer being accepted. According to M. de Fonvielle, the Government refused the experienced aeronaut's proposal on the ground that he required a place in the Champs Elysees, "which it would be necessary to clear of a few shrubs"!

CHAPTER XIX. THE TRAGEDY OF THE ZENITH--THE NAVIGABLE BALLOON

The mechanical air s.h.i.+p had, by this time, as may be inferred, begun seriously to occupy the attention of both theoretical and practical aeronauts. One of the earliest machines deserving of special mention was designed by M. Giffard, and consisted of an elongated balloon, 104 feet in length and 39 feet in greatest diameter, furnished with a triangular rudder, and a steam engine operating a screw. The fire of the engine, which burned c.o.ke, was skilfully protected, and the fuel and water required were taken into calculation as so much ballast to be gradually expended. In this vessel, inflated only with coal gas, and somewhat unmanageable and difficult to balance, the enthusiastic inventor ascended alone from the Hippodrome and executed sundry desired movements, not unsuccessfully. But the trial was not of long duration, and the descent proved both rapid and perilous. Had the trial been made in such a perfect calm as that which prevailed when certain subsequent inventions were tested, it was considered that M. Giffard's vessel would have been as navigable as a boat in the water. This unrivalled mechanician, after having made great advances in the direction of high speed engines of sufficient lightness, proceeded to design a vastly improved dirigible balloon, when his endeavours were frustrated by blindness.

As has been already stated, M. Dupuy de Lome, at the end of the siege of Paris, was engaged in building a navigable balloon, which, owing to the unsettled state of affairs in France, did not receive its trial till two years later. This balloon, which was inflated with pure hydrogen, was of greater capacity than that of M. Giffard, being cigar shaped and measuring 118 feet by 48 feet. It was also provided with an ingenious arrangement consisting of an internal air bag, capable of being either inflated or discharged, for the purpose of keeping the princ.i.p.al envelope always distended, and thus offering the least possible resistance to the wind. The propelling power was the manual labour of eight men working the screw, and the steerage was provided for by a triangular rudder. The trial, which was carried out without mishap, took place in February, 1872, in the Fort of Vincennes, under the personal direction of the inventor, when it was found that the vessel readily obeyed the helm, and was capable of a speed exceeding six miles an hour.

It was not till nine years after this that the next important trial with air s.h.i.+ps was made. The brothers Tissandier will then be found taking the lead, and an appalling incident in the aeronautical career of one of these has now to be recorded.

In the spring of 1875, and with the co-operation of French scientific societies, it was determined to make two experimental voyages in a balloon called the "Zenith," one of these to be of long duration, the other of great height. The first of these had been successfully accomplished in a flight of twenty-four hours' duration from Paris to Bordeaux. It was now April the 15th, and the lofty flight was embarked upon by M. Gaston Tissandier, accompanied by MM. Croce-Spinelli and Sivel. Under competent advice, provision for respiration on emergency was provided in three small balloons, filled with a mixture of air and oxygen, and fitted with indiarubber hose pipes, which would allow the mixture, when inhaled, to pa.s.s first through a wash bottle containing aromatic fluid. The experiments determined on included an a.n.a.lysis of the proportion of carbonic acid gas at different heights by means of special apparatus; spectroscopic observations, and the readings registered by certain barometers and thermometers. A novel and valuable experiment, also arranged, was that of testing the internal temperature of the balloon as compared with that of the external air.

Ascending at 11.30 a.m. under a warm sun, the balloon had by 1 p.m.

reached an alt.i.tude of 16,000 feet, when the external air was at freezing point, the gas high in the balloon being 72 degrees, and at the centre 66 degrees. Ere this height had been fully reached, however, the voyagers had begun to breathe oxygen. At 11.57, an hour previously, Spinelli had written in his notebook, "Slight pain in the ears--somewhat oppressed--it is the gas." At 23,000 feet Sivel wrote in his notebook, "I am inhaling oxygen--the effect is excellent," after which he proceeded to urge the balloon higher by a discharge of ballast. The rest of the terrible narrative has now to be taken from the notes of M.

Tissandier, and as these const.i.tute one of the most thrilling narratives in aeronautical records we transcribe them nearly in full, as given by Mr. Glaisher:--

"At 23,000 feet we were standing up in the car. Sivel, who had given up for a moment, is re-invigorated. Croce-Spinelli is motionless in front of me.... I felt stupefied and frozen. I wished to put on my fur gloves, but, without being conscious of it, the action of taking them from my pocket necessitated an effort that I could no longer make.... I copy, verbatim, the following lines which were written by me, although I have no very distinct remembrance of doing so. They are traced in a hardly legible manner by a hand trembling with cold: 'My hands are frozen. I am all right. We are all all right. Fog in the horizon, with little rounded cirrus. We are ascending. Croce pants; he inhales oxygen. Sivel closes his eyes. Croce also closes his eyes.... Sivel throws out ballast'--these last words are hardly readable. Sivel seized his knife and cut successively three cords, and the three bags emptied themselves and we ascended rapidly. The last remembrance of this ascent which remains clear to me relates to a moment earlier. Croce-Spinelli was seated, holding in one hand a wash bottle of oxygen gas. His head was slightly inclined and he seemed oppressed. I had still strength to tap the aneroid barometer to facilitate the movement of the needle. Sivel had just raised his hand towards the sky. As for myself, I remained perfectly still, without suspecting that I had, perhaps, already lost the power of moving. About the height of 25,000 feet the condition of stupefaction which ensues is extraordinary. The mind and body weaken by degrees, and imperceptibly, without consciousness of it. No suffering is then experienced; on the contrary, an inner joy is felt like an irradiation from the surrounding flood of light. One becomes indifferent. One thinks no more of the perilous position or of danger.

One ascends, and is happy to ascend. The vertigo of the upper regions is not an idle word; but, so far as I can judge from my personal impression, vertigo appears at the last moment; it immediately precedes annihilation, sudden, unexpected, and irresistible.

"When Sivel cut away the bags of ballast at the height of about 24,000 feet, I seemed to remember that he was sitting at the bottom of the car, and nearly in the same position as Croce-Spinelli. For my part, I was in the angle of the car, thanks to which support I was able to hold up; but I soon felt too weak even to turn my head to look at my companions. Soon I wished to take hold of the tube of oxygen, but it was impossible to raise my arm. My mind, nevertheless, was quite clear. I wished to explain, 'We are 8,000 metres high'; but my tongue was, as it were, paralysed. All at once I closed my eyes, and, sinking down inert, became insensible. This was about 1.30 p.m. At 2.8 p.m. I awoke for a moment, and found the balloon rapidly descending. I was able to cut away a bag of ballast to check the speed and write in my notebook the following lines, which I copy:

"'We are descending. Temperature, 3 degrees. I throw out ballast.

Barometer, 12.4 inches. We are descending. Sivel and Croce still in a fainting state at the bottom of the car. Descending very rapidly.'

"Hardly had I written these lines when a kind of trembling seized me, and I fell back weakened again. There was a violent wind from below, upwards, denoting a very rapid descent. After some minutes I felt myself shaken by the arm, and I recognised Croce, who had revived. 'Throw out ballast,' he said to me, 'we are descending '; but I could hardly open my eyes, and did not see whether Sivel was awake. I called to mind that Croce unfastened the aspirator, which he then threw overboard, and then he threw out ballast, rugs, etc.

"All this is an extremely confused remembrance, quickly extinguished, for again I fell back inert more completely than before, and it seemed to me that I was dying. What happened? It is certain that the balloon, relieved of a great weight of ballast, at once ascended to the higher regions.

"At 3.30 p.m. I opened my eyes again. I felt dreadfully giddy and oppressed, but gradually came to myself. The balloon was descending with frightful speed and making great oscillations. I crept along on my knees, and I pulled Sivel and Croce by the arm. 'Sivel! Croce!' I exclaimed, 'Wake up!' My two companions were huddled up motionless in the car, covered by their cloaks. I collected all my strength, and endeavoured to raise them up. Sivel's face was black, his eyes dull, and his mouth was open and full of blood. Croce's eyes were half closed and his mouth was b.l.o.o.d.y.

"To relate what happened afterwards is quite impossible. I felt a frightful wind; we were still 9,700 feet high. There remained in the car two bags of ballast, which I threw out. I was drawing near the earth.

I looked for my knife to cut the small rope which held the anchor, but could not find it. I was like a madman, and continued to call 'Sivel!

Sivel!' By good fortune I was able to put my hand upon my knife and detach the anchor at the right moment. The shock on coming to the ground was dreadful. The balloon seemed as if it were being flattened.

I thought it was going to remain where it had fallen, but the wind was high, and it was dragged across fields, the anchor not catching. The bodies of my unfortunate friends were shaken about in the car, and I thought every moment they would be jerked out. At length, however, I seized the valve line, and the gas soon escaped from the balloon, which lodged against a tree. It was then four o'clock. On stepping out, I was seized with a feverish attack, and sank down and thought for a moment that I was going to join my friends in the next world; but I came to.

I found the bodies of my friends cold and stiff. I had them put under shelter in an adjacent barn. The descent of the 'Zenith' took place in the plains 155 miles from Paris as the crow flies. The greatest height attained in this ascent is estimated at 28,000 feet."

It was in 1884 that the brothers Tissandier commenced experiments with a screw-propelled air s.h.i.+p resembling in shape those constructed by Giffard and Dupuy de Lome, but smaller, measuring only 91 feet by 30 feet, and operated by an electric motor placed in circuit with a powerful battery of b.i.+.c.hromate cells. Two trials were made with this vessel in October, 1883, and again in the following September, when it proved itself capable of holding its course in calm air and of being readily controlled by the rudder.

But, ere this, a number of somewhat similar experiments, on behalf of the French Government, had been entered upon by Captains Renard and Krebs at Chalais-Meudon. Their balloon may be described as fish-shaped, 165 feet long, and 27.5 feet in princ.i.p.al diameter. It was operated by an electric motor, which was capable of driving a screw of large dimensions at forty-eight revolutions per minute. At its first trial, in August, 1884, in dead calm, it attained a velocity of over twelve miles per hour, travelling some two and a half miles in a forward direction, when, by application of the rudder and judicious management, it was manoeuvred homewards, and practically brought to earth at the point of departure.

A more important trial was made on the 12th of the following month, and was witnessed by M. Tissandier, according to whom the aerostat conveying the inventors ascended gently and steadily, drifting with an appreciable breeze until the screw was set in motion and the helm put down, when the vessel was brought round to the wind and held its own until the motor, by an accident, ceased working. A little later the same air s.h.i.+p met with more signal success. On one occasion, starting from Chalais-Meudon, it took a direct course to the N.E., crossing the railway and the Seine, where the aeronauts, stopping the screw, ascertained the velocity of the wind to be approximately five miles an hour. The screw being again put in motion, the balloon was steered to the right, and, following a path parallel to its first, returned to its point of departure. Starting again the same afternoon, it was caused to perform a variety of aerial evolutions, and after thirty-five minutes returned once more to its starting place.

A tabular comparison of the four navigable balloons which we have now described has been given as follows:--

Date. Name. Motor. Vel. p. Sec.

1852 M. Henri Giffard Steam engine 13.12 ft.

1872 M. Dupuy de Lome Muscular force 9.18 ft.

1883 MM. Tissandier Electric motor 9.84 ft.

1884 MM. Renard & Krebs Electric motor 18.04 ft.

About this period, that is in 1883, and really prior to the Meudon experiments, there were other attempts at aerial locomotion not to be altogether pa.s.sed over, which were made also in France, but financed by English money. The experiments were performed by Mr. F. A. Gower, who, writing to Professor Tyndall, claims to have succeeded in "driving a large balloon fairly against the wind by steam power." A melancholy interest will always belong to these trials from the fact that Mr. Gower was subsequently blown out to sea with his balloon, leaving no trace behind.

At this stage it will be well to glance at some of the more important theories which were being mooted as to the possibility of aerial locomotion properly so called. Broadly, there were two rival schools at this time. We will call them the "lighter-than-air-ites" and the "heavier-than-air-ites," respectively. The former were the advocates of the air vessel of which the balloon is a type. The latter school maintained that, as birds are heavier than air, so the air locomotive of the future would be a machine itself heavier than air, but capable of being navigated by a motor yet to be discovered, which would develop proportionate power. Sir H. Maxim's words may be aptly quoted here. "In all Nature," he says, "we do not find a single balloon. All Nature's flying machines are heavier than the air, and depend altogether upon the development of dynamic energy."

The faculty of soaring, possessed by many birds, of which the albatross may be considered a type, led to numerous speculations as to what would const.i.tute the ideal principle of the air motor. Sir G. Cayley, as far back as 1809, wrote a cla.s.sical article on this subject, without, however, adding much to its elucidation. Others after his time conceived that the bird, by sheer habit and practice, could perform, as it were, a trick in balancing by making use of the complex air streams varying in speed and direction that were supposed to intermingle above.

Mr. R. A. Proctor discusses the matter with his usual clear-sightedness.

He premises that the bird may, in actual fact, only poise itself for some ten minutes--an interval which many will consider far too small--without flap of the wings, and, while contending that the problem must be simply a mechanical one, is ready to admit that "the sustaining power of the air on bodies of a particular form travelling swiftly through it may be much greater or very different in character from what is supposed." In his opinion, it is a fact that a flat body travelling swiftly and horizontally will sink towards the ground much more slowly than a similar body moving similarly but with less speed. In proof of this he gives the homely ill.u.s.tration of a flat stone caused to make "ducks and drakes." Thus he contends that the bird accomplishes its floating feat simply by occasional powerful propulsive efforts, combined with perfect balance. From which he deduces the corollary that "if ever the art of flying, or rather of making flying machines, is attained by man, it will be by combining rapid motion with the power of perfect balancing."

It will now appear as a natural and certain consequence that a feature to be introduced by experimentalists into flying machines should be the "Aeroplane," or, in other words, a plane which, at a desired angle, should be driven at speed through the air. Most notable attempts with this expedient were now shortly made by Hiram Maxim, Langley, and others.

But, contemporaneously with these attempts, certain feats with the rival aerostat--the balloon--were accomplished, which will be most fittingly told in this place.

CHAPTER XX. A CHAPTER OF ACCIDENTS.