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   Chapter 4 THE DEVELOPMENT OF BALLOON PHILOSOPHY.

The Dominion of the Air: The Story of Aerial Navigation By John M. Bacon Characters: 18745

Updated: 2017-12-01 00:02


In less than two years not only had the science of ballooning reached almost its highest development, but the balloon itself, as an aerostatic machine, had been brought to a state of perfection which has been but little improved upon up to the present hour. Better or cheaper methods of inflation were yet to be discovered, lighter and more suitable material remained to be manufactured; but the navigation of the air, which hitherto through all time had been beyond man's grasp, had been attained, as it were, at a bound, and at the hands of many different and independent experimentalists was being pursued with almost the same degree of success and safety as to-day.

Nor was this all. There was yet another triumph of the aeronautical art which, within the same brief period, had been to all intents and purposes achieved, even if it had not been brought to the same state of perfection as at the present hour. This was the Parachute. This fact is one which for a sufficient reason is not generally known. It is very commonly supposed that the parachute, in anything like its present form, is a very modern device, and that the art of successfully using it had not been introduced to the world even so lately as thirty years ago. Thus, we find it stated in works of that date dealing with the subject that disastrous consequences almost necessarily attended the use of the parachute, "the defects of which had been attempted to be remedied in various ways, but up to this time without success." A more correct statement, however, would have been that the art of constructing and using a practicable parachute had through many years been lost or forgotten. In actual fact, it had been adopted with every assurance of complete success by the year 1785, when Blanchard by its means lowered dogs and other animals with safety from a balloon. A few years later he descended himself in a like apparatus from Basle, meeting, however, with the misadventure of a broken leg.

But we must go much further back for the actual conception of the parachute, which, we might suppose, may originally have been suggested by the easy floating motion with which certain seeds or leaves will descend from lofty trees, or by the mode adopted by birds of dropping softly to earth with out-stretched wings. M. de la Loubere, in his historical account of Siam, which he visited in 1687-88, speaks of an ingenious athlete who exceedingly diverted the King and his court by leaping from a height and supporting himself in the air by two umbrellas, the handles of which were affixed to his girdle. In 1783, that is, the same year as that in which the balloon was invented, M. le Normand experimented with a like umbrella-shaped contrivance, with a view to its adoption as a fire escape, and he demonstrated the soundness of the principle by descending himself from the windows of a lofty house at Lyons.

It was, however, reserved for M. Jacques Garnerin in 1797 to make the first parachute descent that attracted general attention. Garnerin had previously been detained as a State prisoner in the fortress of Bade, in Hungary, after the battle of Marchiennes in 1793, and during his confinement had pondered on the possibility of effecting his escape by a parachute. His solitary cogitations and calculations resulted, after his release, in the invention and construction of an apparatus which he put to a practical test at Paris before the court of France on October 22nd, 1797. Ascending in a hydrogen balloon to the height of about 2,000 feet, he unhesitatingly cut himself adrift, when for some distance he dropped like a stone. The folds of his apparatus, however, opening suddenly, his fall became instantly checked. The remainder of his descent, though leisurely, occupying, in fact, some twelve minutes, appeared to the spectators to be attended with uncertainty, owing to a swinging motion set up in the car to which he was clinging. But the fact remains that he reached the earth with only slight impact, and entirely without injury.

It appears that Garnerin subsequently made many equally successful parachute descents in France, and during the short peace of 1802 visited London, where he gave an exhibition of his art. From the most reliable accounts of his exploit it would seem that his drop was from a very great height, and that a strong ground wind was blowing at the time, the result of which was that wild, wide oscillations were set up in the car, which narrowly escaped bringing him in contact with the house tops in St. Pancreas, and eventually swung him down into a field, not without some unpleasant scratches.

Nor was Garnerin the only successful parachutist at this period. A Polish aeronaut, Jordaki Kuparento, ascended from Warsaw on the 24th of July, 1804 in a hot air balloon, taking up, as was the custom, an attached furnace, which caused the balloon to take fire when at a great height. Kuparento, however, who was alone, had as a precaution provided himself with a parachute, and with this he seems to have found no difficulty in effecting a safe descent to earth.

It was many years after this that fresh experimentalists, introducing parachutes on new lines and faulty in construction, met with death or disaster. Enough, however, has already been said to show that in the early years we are now traversing in this history a perfectly practicable parachute had become an accomplished fact. The early form is well described by Mr. Monck Mason in a letter to the Morning Herald in 1837, written on the eve of an unrehearsed and fatal experiment made by Mr. Cocking, which must receive notice in due course. "The principle," writes Mr. Monck Mason, "upon which all these parachutes were constructed is the same, and consists simply of a flattened dome of silk or linen from 24 feet to 28 feet in diameter. From the outer margin all around at stated intervals proceed a large number of cords, in length about the diameter of the dome itself, which, being collected together in one point and made fast to another of superior dimensions attached to the apex of the machine, serve to maintain it in its form when expanded in the progress of the descent. To this centre cord likewise, at a distance below the point of junction, varying according to the fancy of the aeronaut, is fixed the car or basket in which he is seated, and the whole suspended from the network of the balloon in such a manner as to be capable of being detached in an instant at the will of the individual by cutting the rope by which it is made fast above."

It followed almost as a matter of course that so soon as the balloon had been made subject to something like due control, and thus had become recognised as a new machine fairly reduced to the service of man, it began to be regarded as an instrument which should be made capable of being devoted to scientific research. Indeed, it may be claimed that, among the very earliest aeronauts, those who had sailed away into the skies and brought back intelligent observations or impressions of the realm of cloud-land, or who had only described their own sensations at lofty altitudes, had already contributed facts of value to science. It is time then, taking events in their due sequence, that mention should be made of the endeavours of various savants, who began about the commencement of the nineteenth century to gather fresh knowledge from the exploration of the air by balloon ascents organised with fitting equipment. The time had now come for promoting the balloon to higher purposes than those of mere exhibition or amusement. In point of fact, it had already in one way been turned to serious practical account. It had been used by the French during military operations in the revolutionary war as a mode of reconnoitring, and not without success, so that when after due trial the war balloon was judged of value a number of similar balloons were constructed for the use of the various divisions of the French army, and, as will be told in its proper place, one, at least, of these was put to a positive test before the battle of Fleurus.

But, returning to more strictly scientific ascents, which began to be mooted at this period, we are at once impressed with the widespread influence which the balloon was exercising on thinking minds. We note this from the fact that what must be claimed to be the first genuine ascent for scientific observation was made in altogether fresh ground, and at so distant a spot as St. Petersburg.

It was now the year 1804, and the Russian Academy had determined on attempting an examination of the physical condition of the higher atmosphere by means of the balloon. The idea had probably been suggested by scientific observations which had already been made on mountain heights by such explorers as De Luc, Saussure, Humboldt, and others. And now it was determined that their results should be tested alongside such observations as could be gathered in the free heaven far removed from any disturbing effects that might be caused by contiguity to earth. The lines of enquiry to which special attention was required were such as would be naturally suggested by the scientific knowledge of the hour, though they may read somewhat quaintly to-day. Would there be any change in the intensity of the magnetic force? Any change in the inclination of the magnetised needle? Woul

d evaporation find a new law? Would solar rays increase in power? What amount of electric matter would be found? What change in the colours produced by the prism? What would be the constitution of the higher and more attenuated air? What physical effect would it have on human and bird life?

The ascent was made at 7.15 on a summer evening by M. Robertson and the Academician, M. Sacharof, to whom we are indebted for the following resume of notes, which have a special value as being the first of their class. Rising slowly, a difference of atmosphere over the Neva gave the balloon a downward motion, necessitating the discharge of ballast. As late as 8.45 p.m. a fine view was obtained of the Newski Islands, and the whole course of the neighbouring river. At 9.20 p.m., when the barometer had fallen from 30 inches to 23 inches, a canary and a dove were dismissed, the former falling precipitately, while the latter sailed down to a village below. All available ballast was now thrown out, including a spare great coat and the remains of supper, with the result that at 9.30 the barometer had fallen to 22 inches, and at this height they caught sight of the upper rim of the sun. The action of heart and lungs remained normal. No stars were seen, though the sky was mainly clear, such clouds as were visible appearing white and at a great height. The echo of a speaking trumpet was heard after an interval of ten seconds. This was substantially the outcome of the experiments. The practical difficulties of carrying out prearranged observations amid the inconvenience of balloon travel were much felt. Their instruments were seriously damaged, and their results, despite most painstaking and praiseworthy efforts, must be regarded as somewhat disappointing.

But ere the autumn of the same year two other scientific ascents, admirably schemed and financed at the public expense, had been successfully carried out at Paris in a war balloon which, as will be told, had at this time been returned from military operations in Egypt. In the first of these, Gay Lussac ascended in company with M. Biot, with very complete equipment. Choosing ten o'clock in the morning for their hour of departure, they quickly entered a region of thin, but wet fog, after which they shot up into denser cloud, which they completely surmounted at a height of 6,500 feet, when they described the upper surface as bearing the resemblance, familiar enough to aeronauts and mountaineers, as of a white sea broken up into gently swelling billows, or of an extended plain covered with snow.

A series of simple experiments now embarked upon showed the behaviour of magnetised iron, as also of a galvanic pile or battery, to remain unaltered. As their altitude increased their pulses quickened, though beyond feeling keenly the contrast of a colder air and of scorching rays of the sun they experienced no physical discomfort. At 11,000 feet a linnet which they liberated fell to the earth almost helplessly, while a pigeon with difficulty maintained an irregular and precipitate flight. A carefully compiled record was made of variations of temperature and humidity, and they succeeded in determining that the upper air was charged with negative electricity. In all this these two accomplished physicists may be said to have carried out a brilliant achievement, even though their actual results may seem somewhat meagre. They not only were their own aeronauts, but succeeded in arranging and carrying out continuous and systematic observations throughout the period of their remaining in the sky.

This voyage was regarded as such a pronounced success that three weeks later, in mid-September, Gay Lussac was induced to ascend again, this time alone, and under circumstances that should enable him to reach an exceptionally high altitude. Experience had taught the advisability of certain modifications in his equipment. A magnet was ingeniously slung with a view of testing its oscillation even in spite of accidental gyrations in the balloon. Thermometers and hygrometers were carefully sheltered from the direct action of the sun, and exhausted flasks were supplied with the object of bringing down samples of upper air for subsequent analysis.

Again it was an early morning ascent, with a barometer on the ground standing at 30.6 inches, and a slightly misty air. Lussac appears to have accomplished the exceedingly difficult task of counting the oscillations of his magnet with satisfaction to himself. At 10,000 feet twenty vibrations occupied 83 seconds, as compared with 84.33 seconds at the earth's surface. The variation of the compass remained unaltered, as also the behaviour of magnetised iron at all altitudes. Keeping his balloon under perfect control, and maintaining a uniform and steady ascent, he at the same time succeeded in compiling an accurate table of readings recording atmospheric pressure, temperature and humidity, and it is interesting to find that he was confronted with an apparent anomaly which will commonly present itself to the aeronaut observer. Up to 12,000 feet the temperature had decreased consistently from 82 degrees to 47 degrees, after which it increased 6 degrees in the next 2,000 feet. This by no means uncommon experience shall be presently discussed. The balloon was now steadily manoeuvred up to 18,636 feet, at which height freezing point was practically reached. Then with a further climb 20,000 feet is recorded, at which altitude the ardent philosopher could still attend to his magnetic observations, nor is his arduous and unassisted task abandoned here, but with marvellous pertinacity he yet struggled upwards till a height of no less than 23,000 feet is recorded, and the thermometer had sunk to 14 degrees F. Four miles and a quarter above the level of the sea, reached by a solitary aerial explorer, whose legitimate training lay apart from aeronautics, and whose main care was the observation of the philosophical instruments he carried! The achievement of this French savant makes a brilliant record in the early pages of our history.

It is not surprising that Lussac should own to having felt no inconsiderable personal discomfort before his venture was over. In spite of warm clothing he suffered greatly from cold and benumbed fingers, not less also from laboured breathing and a quickened pulse; headache supervened, and his throat became parched and unable to swallow food. In spite of all, he conducted the descent with the utmost skill, climbing down quietly and gradually till he alighted with gentle ease at St. Gourgen, near Rouen. It may be mentioned here that the analysis of the samples of air which he had brought down proved them to contain the normal proportion of oxygen, and to be essentially identical, as tested in the laboratory, with the free air secured at the surface of the earth.

The sudden and apparently unaccountable variation in temperature recorded by Lussac is a striking revelation to an aerial observer, and becomes yet more marked when more sensitive instruments are used than those which were taken up on the occasion just related. It will be recorded in a future chapter how more suitable instruments came in course of time to be devised. It is only necessary to point out at this stage that instruments which lack due sensibility will unavoidably read too high in ascents, and too low in descents where, according to the general law, the air is found to grow constantly colder with elevation above the earth's surface. It is strong evidence of considerable efficiency in the instruments, and of careful attention on the part of the observer, that Lussac was able to record the temporary inversion of the law of change of temperature above-mentioned. Had he possessed modern instrumental equipment he would have brought down a yet more remarkable account of the upper regions which he visited, and learned that the variations of heat and cold were considerably more striking than he supposed.

With a specially devised instrument used with special precautions, the writer, as will be shown hereafter, has been able to prove that the temperature of the air, as traversed in the wayward course of a balloon, is probably far more variable and complex than has been recorded by most observers.

The exceptional height claimed to have been reached by Gay Lassac need not for a moment be questioned, and the fact that he did not experience the same personal inconvenience as has been complained of by mountain climbers at far less altitudes admits of ready explanation. The physical exertion demanded of the mountaineer is entirely absent in the case of an aeronaut who is sailing at perfect ease in a free balloon. Moreover, it must be remembered that-a most important consideration-the aerial voyager, necessarily travelling with the wind, is unconscious, save at exceptional moments, of any breeze whatever, and it is a well-established fact that a degree of cold which might be insupportable when a breeze is stirring may be but little felt in dead calm. It should also be remembered, in duly regarding Gay Lussac's remarkable record, that this was not his first experience of high altitudes, and it is an acknowledged truth that an aeronaut, especially if he be an enthusiast, quickly becomes acclimatised to his new element, and sufficiently inured to its occasional rigours.

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