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an whom it is impossible to adduce a more careful witness； we find him recording how on mountain heights he met with winds turbulent and unconfined； yet holding courses 〃like rivers within their beds。〃
It is in tracing the trend of upper air streams； to whose wayward courses and ever varying conditions we are now to be introduced； that much of our most valuable information has come； affecting the possibility of forecasting British wind and weather。 It should need no insisting on that the data required by meteorologists are not sufficiently supplied by the readings of instruments placed on or near the ground； or by the set of the wind as determined by a vane planted on the top of a pole or roof of a building。 The chief factors in our meteorology are rather those broader and deeper conditions which obtain in higher regions necessarily beyond our ken； until those regions are duly and diligently explored。
Mr。 Glaisher's estimate of the utility of the balloon as an instrument of research； formed at the conclusion of his aeronautical labours； has a special value and significance。 Speaking with all the weight attaching to so trained and eminent an observer； he declares； 〃The balloon； considered as an instrument for vertical exploration； presents itself to us under a variety of aspects； each of which is fertile in suggestions。 Regarding the atmosphere as the great laboratory of changes which contain the germ of future dis discoveries； to belong respectively； as they unfold； to the chemist and meteorologist； the physical relation to animal life of different heights； the form of death which at certain elevations waits to accomplish its destruction； the effect of diminished pressure upon individuals similarly placed； the comparison of mountain ascents with the experiences of aeronauts； are some of the questions which suggest themselves and faintly indicate enquiries which naturally ally themselves to the course of balloon experiments。 Sufficiently varied and important； they will be seen to rank the balloon as a valuable aid to the uses of philosophy； and rescue it from the impending degradation of continuing a toy fit only to be exhibited or to administer to the pleasures of the curious and lovers of adventure。〃
The words of the same authority as to the possible practical development of the balloon as an aerial machine should likewise be quoted； and will appear almost prophetic。 〃In England the subject of aero…station has made but little progress； and no valuable invention has arisen to facilitate travelling in the air。 In all my ascents I used the balloon as I found it。 The desire which influenced me was to ascend to the higher regions and travel by its means in furtherance of a better knowledge of atmospheric phenomena。 Neither its management nor its improvement formed a part of my plan。 I soon found that balloon travelling was at the mercy of the wind； and I saw no probability of any method of steering balloons being obtained。 It even appeared to me that the balloon itself； admirable for vertical ascents； was not necessarily a first step in aerial navigation； and might possibly have no share in the solution of the problem。 It was this conviction that led to the formation of the Aeronautical Society a few years since under the presidency of the Duke of Argyll。 In the number of communications made to this society it is evident that many minds are taxing their ingenuity to discover a mode of navigating the air； all kinds of imaginary projects have been suggested； some showing great mechanical ingenuity； but all indicating the want of more knowledge of the atmosphere itself。 The first great aim of this society is the connecting the velocity of the air with its pressure on plane surfaces at various inclinations。
〃There seems no prospect of obtaining this relation otherwise than by a careful series of experiments。〃
CHAPTER XIV。 THE HIGHEST ASCENT ON RECORD。
Mr。 Glaisher's instrumental outfit was on an elaborate and costly scale； and the programme of experimental work drawn up for him by the Committee of the British Association did not err on the side of too much modesty。 In the first place the temperature and moisture of the atmosphere were to be examined。 Observations on mountain sides had determined that thermometers showed a decrease of 1 degree F。 for every 300 feet； and the accuracy of this law was particularly to be tested。 Also； investigations were to be made as to the distribution of vapour below the clouds； in them； and above them。 Then careful observations respecting the dew point were to be undertaken at all accessible heights； and； more particularly； up to those heights where man may be resident or troops may be located。 The comparatively new instrument； the aneroid barometer； extremely valuable； if only trustworthy； by reason of its sensibility； portability and safety； was to be tested and compared with the behaviour of a reliable mercurial barometer。 Electrical conditions were to be examined； the presence of ozone tested； the vibration of a magnet was again to be resorted to to determine how far the magnetism of the earth might be affected by height。 The solar spectrum was to be observed； air was to be collected at different heights for analysis； clouds； also upper currents； were to be reported on。 Further observations were to be made on sound； on solar radiation； on the actinic action of the sun； and on atmospheric phenomena in general。
All this must be regarded as a large order where only a very limited number of ascents were contemplated； and it may be mentioned that some of the methods of investigation； as； for instance； the use of ozone papers； would now be generally considered obsolete； while the mechanical aspiration of thermometers by a stream of air； which； as we have pointed out； was introduced by Welsh； and which is strongly insisted on at the present day； was considered unnecessary by Mr。 Glaisher in the case of wet and dry bulb hygrometers。 The entire list of instruments； as minutely described by the talented observer； numbered twenty…two articles； among which were such irreproachable items as a bottle of water and a pair of scissors。
The following is a condensed account； gathered from Mr。 Glaisher's own narrative； of his first ascent； which has been already briefly sketched in these pages by the hand of Mr。 Coxwell。 Very great difficulties were experienced in the inflation； which operation appeared as if it would never be completed； for a terrible W。S。W。 wind was constantly blowing； and the movements of the balloon were so great and so rapid that it was impossible to fix a single instrument in its position before quitting the earth； a position of affairs which； says Mr。 Glaisher； 〃was by no means cheering to a novice who had never before put his foot in the car of a balloon；〃 and when； at last； at 9。42 a。m。； Mr。 Coxwell cast off； there was no upward motion； the car simply dragging on its side till the expiration of a whole minute； when the balloon lifted； and in six minutes reached the first cloud at an altitude of 4；467 feet。 This cloud was passed at 5；802 feet； and further cloud encountered at 2；000 feet further aloft。 Four minutes later； the ascent proceedin