the dominion of the air-第3节
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The perfecting of his system became then simply a question of practice and experience； and had young athletes only been trained from early years to the new art it seems reasonable to suppose that some crude approach to human flight would have been effected。 Modifications and improvements in construction would soon have suggested themselves； as was the case with the bicycle； which in its latest developments can scarcely be recognised as springing from the primitive 〃bone…shaker〃 of thirty…three years ago。 We would suggest the idea to the modern inventor。 He will in these days； of course； find lighter materials to hand。 Then he will adopt some link motion for the legs in place of leather thongs； and will hinge the paddle blades so that they open out with the forward stroke； but collapse with the return。 Then look on another thirty…three yearsa fresh generationand our youth of both sexes may find a popular recreation in graceful aerial exercise。 The pace is not likely to be excessive； and molestations from disguised policemennot physically adapted； by the way； to rapid flightneed not be apprehended。
One of the best tests of Besnier's measure of success is supplied by the fact that he had pupils as well as imitators。 First on this list must be mentioned a Mr。 Baldwin； a name which； curiously enough； twice over in modern times comes into the records of bold aerial exploits。 This individual； it appears； purchased a flying outfit of Besnier himself； and surpassed his master in achievement。 A little later one Dante contrived some modification of the same apparatus； with which he pursued the new mode of progress till he met with a fractured thigh。
But whatever the imitators of Besnier may have accomplished； to the honest smith must be accorded the full credit of their success； and with his simple； but brilliant； record left at flood mark； the tide of progress ebbed back again； while mankind ruminated over the great problem in apparent inactivity。 But not for long。 The air…pump about this period was given to the world； and chemists were already busy investigating the nature of gases。 Cavallo was experimenting on kindred lines； while in our own land the rival geniuses of Priestley and Cavendish were clearing the way to make with respect to the atmosphere the most important discovery yet dreamed of。 In recording this dawn of a new era； however； we should certainly not forget how； across the Atlantic； had arisen a Rumford and a Franklin； whose labours were destined to throw an all…important sidelight on the pages of progress which we have now to chronicle。
CHAPTER II。 THE INVENTION OF THE BALLOON。
It was a November night of the year 1782； in the little town of Annonay； near Lyons。 Two young men； Stephen and Joseph Montgolfier； the representatives of a firm of paper makers； were sitting together over their parlour fire。 While watching the smoke curling up the chimney one propounded an idea by way of a sudden inspiration： 〃Why shouldn't smoke be made to raise bodies into the air？〃
The world was waiting for this utterance； which； it would seem； was on the tip of the tongue with many others。 Cavendish had already discovered what he designated 〃inflammable air；〃 though no one had as yet given it its later title of hydrogen gas。 Moreover； in treating of this gasDr。 Black of Edinburgh； as much as fifteen years before the date we have now arrived at； had suggested that it should be made capable of raising a thin bladder in the air。 With a shade more of good fortune； or maybe with a modicum more of leisure； the learned Doctor would have won the invention of the balloon for his own country。 Cavallo came almost nearer； and actually putting the same idea into practice； had succeeded in the spring of 1782 in making soap bubbles blown with hydrogen gas float upwards。 But he had accomplished no more when； as related； in the autumn of the same year the brothers Montgolfier conceived the notion of making bodies 〃levitate〃 by the simpler expedient of filling them with smoke。
This was the crude idea； the application of which in their hands was soon marked with notable success。 Their own trade supplied ready and suitable materials for a first experiment； and； making an oblong bag of thin paper a few feet in length； they proceeded to introduce a cloud of smoke into it by holding crumpled paper kindled in a chafing dish beneath the open mouth。 What a subject is there here for an imaginative painter！ As the smoky cloud formed within； the bag distended itself； became buoyant； and presently floated to the ceiling。 The simple trial proved a complete success； due； as it appeared to them； to the ascensive power of a cloud of smoke。
An interesting and more detailed version of the story is extant。 While the experiment was in progress a neighbour； the widow of a tradesman who had been connected in business with the firm； seeing smoke escaping into the room； entered and stood watching the proceedings； which were not unattended with difficulties。 The bag； half inflated； was not easy to hold in position over the chafing dish； and rapidly cooled and collapsed on being removed from it。 The widow noting this； as also the perplexity of the young men； suggested that they should try the result of tying the dish on at the bottom of the bag。 This was the one thing wanted to secure success； and that good lady； whose very name is unhappily lost； deserves an honoured place in history。 It was unquestionably the adoption of her idea which launched the first balloon into space。
The same experiment repeated in the open air proving a yet more pronounced success； more elaborate trials were quickly developed； and the infant balloon grew fast。 One worthy of the name； spherical in shape and of some 600 cubic feet capacity； was now made and treated as before； with the result that ere it was fully inflated it broke the strings that held it and sailed away hundreds of feet into the air。 The infant was fast becoming a prodigy。 Encouraged by their fresh success； the inventors at once set about preparations for the construction of a much larger balloon some thirty…five feet diameter （that is； of about 23；000 cubic feet capacity）； to be made of linen lined with paper and this machine； launched on a favourable day in the following spring； rose with great swiftness to fully a thousand feet； and travelled nearly a mile from its starting ground。
Enough； the time was already ripe for a public demonstration of the new invention； and accordingly the 5th of the following June witnessed the ascent of the same balloon with due ceremony and advertisement。 Special pains were taken with the inflation； which was conducted over a pit above which the balloon envelope was slung； and in accordance with the view that smoke was the chief lifting power； the fuel was composed of straw largely mixed with wool。 It is recorded that the management of the furnace needed the attention of two men only； while eight men could hardly hold the impatient balloon in restraint。 The inflation； in spite of the fact that the fuel chosen was scarcely the best for the purpose； was conducted remarkable expedition； and on being released； the craft travelled one and a half miles into the air； attaining a height estimated at over 6；000 feet。
From this time the tide of events in the aeronautical world rolls on in full flood； almost every half…year marking a fresh epoch； until a new departure in the infant art of ballooning was already on the point of being reached。 It had been erroneously supposed that the ascent of the Montgolfier balloon had been due； not to the rarefaction of the air within itwhich was its true causebut to the evolution of some light gas disengaged by the nature of the fuel used。 It followed； therefore； almost as a matter of course； that chemists； who； as stated in the last chapter； were already acquainted with so…called 〃inflammable air；〃 or hydrogen gas； grasped the fact that this gas would serve better than any other for the purposes of a balloon。 And no sooner had the news of the Montgolfiers' success reached Paris than a subscription was raised； and M。 Charles； Professor of Experimental Philosophy； was appointed； with the assistance of M。 Roberts； to superintend the construction of a suitable balloon and its inflation by the proposed new method。
The task was one of considerable difficulty； owing partly to the necessity of procuring some material which would prevent the escape of the lightest and most subtle gas known； and no less by reason of the difficulty of preparing under pressure a sufficient quantity of gas itself。 The experiment； sound enough in theory； was eventually carried through after several instructive failures。 A suitable material was found in 〃lustring；〃 a glossy silk cloth varnished with a solution of caoutchouc； and this being formed into a balloon only thirteen feet in diameter and fitted without other aperture than a stopcock； was after several attempts filled with hydrogen gas prepared in the usual way by the action of dilute sulphuric acid on scrap iron。
The preparations completed； one last and all…important mistake was made by closing the stop…cock before the balloon was dismissed； the disastrous and unavoidable result of this
