the dominion of the air-第30部分
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ortable retirement at Upper Holloway。 The grand old man pointed to a well…filled portfolio in the corner of his room； in which； he said； were accounts of all his travels； that would require a lifetime to peruse and put in order。 Green then took his visitor to the end of the narrow court； and； opening the door of an outhouse； showed him the old Nassau balloon。 〃Here is my car；〃 he said； touching it with a kind of solemn respect； 〃which； like its old pilot； now reposes quietly after a long and active career。 Here is the guide rope which I imagined in former years； and which has been found very useful to aeronauts。。。。 Now my life has past and my time has gone by。。。。 Though my hair is white and my body too weak to help you； I can still give you my advice； and you have my hearty wishes for your future。〃
It was but shortly after this； on March 26； 1870； that Charles Green passed away in the 85th year of his age。
De Fonvielle's colleague； M。 Gaston Tissandier； was on one occasion accidentally brought to visit the resting place of the earliest among aeronauts； whose tragic death occurred while Charles Green himself was yet a boy。 In a stormy and hazardous descent Tissandier； under the guidance of M。 Duruof； landed with difficulty on the sea coast of France； when one of the first to render help was a lightkeeper of the Griz…nez lighthouse； who gave the information that on the other side of the hills； a few hundred yards from the spot where they had landed； was the tomb of Pilatre de Rozier； whose tragical death has been recorded in an early chapter。 A visit to the actual locality the next day revealed the fact that a humble stone still marked the spot。
Certain scientific facts and memoranda collected by the talented French aeronaut whom we are following are too interesting to be omitted。 In the same journey to which we have just referred the voyagers； when nearly over Calais； were witnesses from their commanding standpoint of a very striking phenomenon of mirage。 Looking in the direction of England； the far coast line was hidden by an immense veil of leaden…coloured cloud； and； following this cloud wall upward to detect where it terminated； the travellers saw above it a greenish layer like that of the surface of the sea； on which was detected a little black point suggesting a walnut shell。 Fixing their eyes on this black spot； they presently discerned it to be a ship sailing upside down upon an aerial ocean。 Soon after； a steamer blowing smoke； and then other vessels； added themselves to the illusory spectacle。
Another wonder detected； equally striking though less uncommon； was of an acoustical nature； the locality this time being over Paris。 The height of the balloon at this moment was not great； and； moreover； was diminishing as it settled down。 Suddenly there broke in upon the voyagers a sound as of a confused kind of murmur。 It was not unlike the distant breaking of waves against a sandy coast； and scarcely less monotonous。 It was the noise of Paris that reached them； as soon as they sank to within 2；600 feet of the ground； but it disappeared at once when they threw out just sufficient ballast to rise above that altitude。
It might appear to many that so strange and sudden a shutting out of a vast sound occurring abruptly in the free upper air must have been more imaginary than real； yet the phenomenon is almost precisely similar to one coming within the experience the writer； and vouched for by his son and daughter； as also by Mr。 Percival Spencer； all of whom were joint observers at the time； the main point of difference in the two cases being the fact that the 〃region of silence〃 was recorded by the French observers as occurring at a somewhat lower level。 In both cases there is little doubt that the phenomenon can be referred to a stratum of disturbed or non…homogeneous air； which may have been very far spread； and which is capable of acting as a most opaque sound barrier。
Attention has often been called in these pages to the fact that the action of the sun on an inflated balloon； even when the solar rays may be partially obscured and only operative for a few passing moments； is to give sudden and great buoyancy to the balloon。 An admirable opportunity for fairly estimating the dynamic effect of the sun's rays on a silk globe； whose fabric was half translucent； was offered to the French aeronauts when their balloon was spread on the grass under repair； and for this purpose inflated with the circumambient air by means of a simple rotatory fan。 The sun coming out； the interior of the globe quickly became suffocating； and it was found that； while the external temperature recorded 77 degrees； that of the interior was in excess of 91 degrees。
CHAPTER XVII。 ADVENTURE AND ENTERPRISE。
A balloon which has become famous in history was frequently
used in the researches of the French aeronauts mentioned in our last chapter。 This was known as 〃The Giant；〃 the creation of M。 Nadar； a progressive and practical aeronaut； who had always entertained ambitious ideas about aerial travel。
M。 Nadar had been editor of L'Aeronaut； a French journal devoted to the advancement of aerostation generally。 He had also strongly expressed his own views respecting the possibility of constructing air ships that should be subject to control and guidance when winds were blowing。 His great contention was that the dirigible air ship would； like a bird； have to be made heavier than the medium in which it was to fly。 As he put it； a balloon could never properly become a vessel。 It would only be a buoy。 In spite of any number of accessories； paddles； wings； fans； sails； it could not possibly prevent the wind from bodily carrying away the whole concern。
After this strong expression of opinion； it may appear somewhat strange that such a bold theoriser should at once have set himself to construct the largest gas balloon on record。 Such； however； was the case and the reason urged was not otherwise than plausible。 For； seeing that a vast sum of money would be needed to put his theories into practice； M。 Nadar conceived the idea of first constructing a balloon so unique and unrivalled that it should compel public attention in a way that no other balloon had done before； and so by popular exhibitions bring to his hand such sums as he required。 A proper idea of the scale of this huge machine can be easily gathered。 The largest balloons at present exhibited in this country are seldom much in excess of 50；000 cubic feet capacity。 Compared with these the 〃Great Nassau Balloon；〃 built by Charles Green； which has been already sufficiently described； was a true leviathan； while Coxwell's 〃Mammoth〃 was larger yet； possessing a content； when fully inflated； of no less than 93；000 cubic feet； and measuring over 55 feet in diameter。 This； however； as will be seen； was but a mere pigmy when compared with 〃The Giant；〃 which； measuring some 74 feet in diameter； possessed the prodigious capacity of 215；000 cubic feet。
But the huge craft possessed another novelty besides that of exceptional size。 It was provided with a subsidiary balloon； called the 〃Compensator；〃 and properly the idea of M。 L。 Godard； the function of which was to receive any expulsion of gas in ascending； and thus to prevent loss during any voyage。 The specification of this really remarkable structure may be taken from M。 Nadar's own description。 The globe in itself was for greater strength virtually double； consisting of two identical balloons； one within the other； each made of white silk of the finest quality； and costing about 5s。 4d。 per yard。 No less than 22；000 yards of this silk were required； and the sewing up of the gores was entirely done by hand。 The small compensating balloon was constructed to have a capacity of about 3；500 cubic feet； and the whole machine； when fully inflated； was calculated to lift 4 1/2 tons。 With this enormous margin of buoyancy； M。 Nadar determined on making the car of proportionate and unparalleled dimensions； and of most elaborate design。 It contained two floors； of which the upper one was open； the height of all being nearly 7 feet； with a width of about 13 feet。 Then what was thought to be due provision was made for possible emergencies。 It might descend far from help or habitations； therefore means were provided for attaching wheels and axles。 Again； the chance of rough impact had to be considered； and so canes； to act as springs； were fitted around and below。 Once again； there was the contingency of immersion to be reckoned with； therefore there were provided buoys and water…tight compartments。 Further than this； unusual luxuries were added； for there were cabins； one for the captain at one end； and another with three berths for passengers at the other。 Nor was this all； for there was； in addition； a larder； a lavatory； a photographic room； and a printing office。 It remains now only to tell the tale of how this leviathan of the air acquitted itself。
The first ascent was made on the 4th of October； 1853； from the Champ de Mars； and no fewer than fifteen living souls were launched together into the sky。 Of these Nadar was captain； with the brothers Godard lieutenants。 There was the Prince de Sayn…Wittgenstein； there was the Count de St。 Martin； above all； there was a lady； the Princess de la Tour d'Auvergne。 The balloon came to earth at 9 o'clock at night near Meaux； and； considering all the provision which had been made to guard against rough landing； it can hardly be said that the descent was a happy one。 It appears that the car dragged on its side for nearly a mile； and the passengers； far from finding security in the seclusion of the inner chambers； were glad to clamber out above and cling； as best they might； to the ropes。
Many of the party were bruised more or less severely； though no one was seriously injured； and it was reported that such fragile articles as crockery； cakes； confectionery； and wine bottles to the number of no less than thirty…seven； were afterwards discovered to be intact； and received due attention。 It is further stated that the descent was decided on contrary to the wishes of the captain； but in deference to the judgment of the experienced MM。 Godard； it being apparently their co
