the dominion of the air-第8节
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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？ Would 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 atmosphe
