the dominion of the air-第47节
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； employing kites to determine the upper currents； and to carry thermometers into higher strata of the air。 Franklin's kite and its application is matter of history。 Many since that period made experiments more or less in earnest to obtain atmospheric observations by means of kites； but probably the first in England； at least to obtain satisfactory results； was Mr。 Douglas Archibald； who； during the eighties； was successful in obtaining valuable wind measurements； as also other results； including aerial photographs； at varying altitudes up to 1；000 or 1；200 feet。 From that period the records of serious and systematic kite flying must be sought in America。 Mr。 W。 A。 Eddy was one of the pioneers； and a very serviceable tailless kite； in which the cross…bar is bowed away from the wind； is his invention； and has been much in use。 Mr。 Eddy established his kite at Blue Hillthe now famous kite observatoryand succeeded in lifting self…recording meteorological instruments to considerable heights。 The superiority of readings thus obtained is obvious from the fact that fresh air…streams are constantly playing on the instruments。
A year or two later a totally dissimilar kite was introduced by Mr。 Lawrence Hargrave； of Sydney； Australia。 This invention； which has proved of the greatest utility and efficiency； would； from its appearance； upset all conventional ideas of what a kite should be； resembling in its simplest form a mere box； minus the back and front。 Nevertheless； these kites； in their present form； have carried instruments to heights of upwards of two miles； the restraining line being fine steel piano wire。
But another and most efficient kite； admirably adapted for many most important purposes； is that invented by Major Baden…Powell。 The main objects originally aimed at in the construction of this kite related to military operations； such as signalling； photography； and the raising of a man to an elevation for observational purposes。 In the opinion of the inventor； who is a practiced aeronaut； a wind of over thirty miles an hour renders a captive balloon useless； while a kite under such conditions should be capable of taking its place in the field。 Describing his early experiments； Major； then Captain； Baden…Powell； stated that in 1894； after a number of failures； he succeeded with a hexagonal structure of cambric； stretched on a bamboo framework 36 feet high； in lifting a mannot far； but far enough to prove that his theories were right。 Later on； substituting a number of small kites for one big one； he was； on several occasions； raised to a height of 100 feet； and had sent up sand bags； weighing 9 stone； to 300 feet； at which height they remained suspended nearly a whole day。
This form of kite； which has been further developed； has been used in the South African campaign in connection with wireless telegraphy for the taking of photographs at great heights； notably at Modder River； and for other purposes。
It has been claimed that the first well…authenticated occasion of a man being raised by a kite was when at Pirbright Camp a Baden…Powell kite； 30 feet high； flown by two lines； from which a basket was suspended； took a man up to a height of 10 feet。 It is only fair； however； to state that it is related that more than fifty years ago a lady was lifted some hundred feet by a great kite constructed by one George Pocock； whose machine was designed for an observatory in war； and also for drawing carriages along highways。
CHAPTER XXIV。 ANDREE AND HIS VOYAGES
Among many suggestions； alike important and original； due to Major Baden…Powell； and coming within the field of aeronautics； is one having reference to the use of balloons for geographical research generally and more particularly for the exploration of Egypt； which； in his opinion； is a country possessing many most desirable qualifications on the score of prevailing winds； of suitable base； and of ground adapted for such steering as may be effected with a trail rope。 At the Bristol meeting of the British Association the Major thus propounded his method： 〃I should suggest several balloons； one of about 60；000 cubic feet； and； say； six smaller ones of about 7；000 cubic feet； then； if one gets torn or damaged； the others might remain intact。 After a time； when gas is lost； one of the smaller ones could be emptied into the others； and the exhausted envelope discharged as ballast； the smaller balloons would be easier to transport by porters than one big one； and they could be more easily secured on the earth during contrary winds。 Over the main balloon a light awning might be rigged to neutralise； as far as possible； the changes of temperature。 A lightning conductor to the top of the balloon might be desirable。 A large sail would be arranged； and a bifurcated guide rope attached to the end of a horizontal pole would form an efficient means of steering。 The car would be boat…shaped and waterproof； so that it could be used for a return journey down a river。 Water tanks would be fitted。〃
The reasonableness of such a scheme is beyond question； even without the working calculations with which it is accompanied； but； ere these words were spoken； one of the most daring explorers that the world has known had begun to put in practice a yet bolder and rasher scheme of his own。 The idea of reaching the North Pole by means of balloons appears to have been entertained many years ago。 In a curious work； published in Paris in 1863 by Delaville Dedreux； there is a suggestion for reaching the North Pole by an aerostat which should be launched from the nearest accessible point； the calculation being that the distance from such a starting place to the Pole and back again would be only some 1；200 miles； which could be covered in two days； supposing only that there could be found a moderate and favourable wind in each direction。 Mr。 C。 G。 Spencer also wrote on the subject； and subsequently Commander Cheyne proposed a method of reaching the Pole by means of triple balloons。 A similar scheme was advocated in yet more serious earnest by M。 Hermite in the early eighties。
Some ten years later than this M。 S。 A。 Andree； having obtained sufficient assistance； took up the idea with the determined intention of pushing it to a practical issue。 He had already won his spurs as an aeronaut； as may be briefly told。 In October； 1893； when making an ascent for scientific purposes； his balloon got carried out over the Baltic。 It may have been the strength of the wind that had taken him by surprise； but； there being now no remedy； it was clearly the speed and persistence of the wind that alone could save him。 If a chance vessel could not； or would not； 〃stand by；〃 he must make the coast of Finland or fall in the sea； and several times the fall in the sea seemed imminent as his balloon commenced dropping。 This threatened danger induced him to cast away his anchor； after which the verge of the Finland shore was nearly reached； when a change of wind began to carry him along the rocky coast； just as night was setting in。
Recognising his extreme danger； Andree stood on the edge of the car； with a bag of ballast ready for emergencies。 He actually passed over an island； on which was a building with a light； but failed to effect a landing； and so fell in the sea on the farther side； but； the balloon presently righting itself； Andree； now greatly exhausted； made his last effort； and as he rose over the next cliff jumped for his life。 It was past 7 p。m。 when he found himself once again on firm ground； but with a sprained leg and with no one within call。 Seeking what shelter he could； he lived out the long night； and； being now scarce able to stand； took off his clothes and waved them for a signal。 This signal was not seen； yet shortly a boat put off from an islandthe same that he had passed the evening before… …and rowed towards him。 The boatman overnight had seen a strange sail sweeping over land and sea； and he had come in quest of it； bringing timely succour to the castaway。
Briefly stated； Andree's grand scheme was to convey a suitable balloon； with means for inflating it； as also all necessary equipment； as far towards the Pole as a ship could proceed； and thence； waiting for a favourable wind； to sail by sky until the region of the Pole should be crossed； and some inhabited country reached beyond。 The balloon was to be kept near the earth； and steered； as far as this might be practicable； by means of a trail rope。 The balloon； which had a capacity of nearly 162；000 cubic feet； was made in Paris； and was provided with a rudder sail and an arrangement whereby the hang of the trail rope could be readily shifted to different positions on the ring。 Further； to obviate unnecessary diffusion and loss of gas at the mouth； the balloon was fitted with a lower valve； which would only open at a moderate pressure； namely； that of four inches of water。
All preparations were completed by the summer of 1896； and on June 7th the party embarked at Gothenburg with all necessaries on board； arriving at Spitzbergen on June 21st。 Andree； who was to be accompanied on his aerial voyage by two companions； M。 Nils Strindberg and Dr。 Ekholm； spent some time in selecting a spot that would s
