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TRIUMPHANT〃
No doubt many of those who saw that picture were reminded of the
great sacrifices made by man in the past。 In the wake of the aviator there
are many memorial stones of mournful significance。
It says much for the pluck and perseverance of aviators that they have
been willing to run the great risks which ever accompany their efforts。
Four years of the Great War have shown how splendidly airmen have risen
to the great demands made upon them。 In dispatch after dispatch from the
front； tribute has been paid to the gallant and devoted work of the Royal
Flying Corps and the Royal Naval Air Service。 In a long and bitter
struggle British airmen have gradually asserted their supremacy in the air。
In all parts of the globe； in Egypt； in Mesopotamia； in Palestine； in Africa；
the airman has been an indispensable adjunct of the fighting forces。 Truly
it may be said that mastery of the air is the indispensable factor of final
victory。
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THE MASTERY OF THE AIR
CHAPTER II The French Paper…maker who
Invented the Balloon
In the year 1782 two young Frenchmen might have been seen one
winter night sitting over their cottage fire； performing the curious
experiment of filling paper bags with smoke； and letting them rise up
towards the ceiling。 These young men were brothers； named Stephen and
Joseph Montgolfier； and their experiments resulted in the invention of the
balloon。
The brothers； like all inventors； seem to have had enquiring minds。
They were for ever asking the why and the wherefore of things。 〃Why
does smoke rise？〃 they asked。 〃Is there not some strange power in the
atmosphere which makes the smoke from chimneys and elsewhere rise in
opposition to the force of gravity？ If so； cannot we discover this power；
and apply it to the service of mankind？〃
We may imagine that such questions were in the minds of those two
French paper…makers； just as similar questions were in the mind of James
Watt when he was discovering the power of steam。 But one of the most
important attributes of an inventor is an infinite capacity for taking pains；
together with great patience。
And so we find the two brothers employing their leisure in what to us
would； be a childish pastime； the making of paper balloons。 The story tells
us that their room was filled with smoke； which issued from the windows
as though the house were on fire。 A neighbour； thinking such was the case；
rushed in； but； on being assured that nothing serious was wrong； stayed to
watch the tiny balloons rise a little way from the thin tray which contained
the fire that made the smoke with which the bags were filled。 The
experiments were not altogether successful； however； for the bags rarely
rose more than a foot or so from the tray。 The neighbour suggested that
they should fasten the thin tray on to the bottom of the bag； for it was
thought that the bags would not ascend higher because the smoke became
cool； and if the smoke were imprisoned within the bag much better results
would be obtained。 This was done； and； to the great joy of the brothers and
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THE MASTERY OF THE AIR
their visitor； the bag at once rose quickly to the ceiling。
But though they could make the bags rise their great trouble was that
they did not know the cause of this ascent。 They thought； however； that
they were on the eve of some great discovery； and； as events proved； they
were not far wrong。 For a time they imagined that the fire they had used
generated some special gas； and if they could find out the nature of this
gas； and the means of making it in large quantities； they would be able to
add to their success。
Of course； in the light of modern knowledge； it seems strange that the
brothers did not know that the reason the bags rose； was not because of
any special gas being used； but owing to the expansion of air under the
influence of heat； whereby hot air tends to rise。 Every schoolboy above the
age of twelve knows that hot air rises upwards in the atmosphere； and that
it continues to rise until its temperature has become the same as that of the
surrounding air。
The next experiment was to try their bags in the open air。 Choosing a
calm； fine day； they made a fire similar to that used in their first
experiments； and succeeded in making the bag rise nearly 100 feet。 Later
on； a much larger craft was built； which was equally successful。
And now we must leave the experiments of the Montgolfiers for a
moment； and turn to the discovery of hydrogen gas by Henry Cavendish； a
well…known London chemist。 In 1766 Cavendish proved conclusively that
hydrogen gas was not more than one…seventh the weight of ordinary air。 It
at once occurred to Dr。 Black； of Glasgow； that if a thin bag could be filled
with this light gas it would rise in the air； but for various reasons his
experiments did not yield results of a practical nature for several years。
Some time afterwards； about a year before the Montgolfiers
commenced their experiments which we have already described； Tiberius
Cavallo； an Italian chemist； succeeded in making； with hydrogen gas；
soap…bubbles which rose in the air。 Previous to this he had experimented
with bladders and paper bags； but the bladders he found too heavy； and the
paper too porous。
It must not be thought that the Montgolfiers experimented solely with
hot air in the inflation of their balloons。 At one time they used steam； and；
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THE MASTERY OF THE AIR
later on； the newly…discovered hydrogen gas； but with both these agents
they were unsuccessful。 It can easily be seen why steam was of no use；
when we consider that paper was employed； hydrogen； too； owed its lack
of success to the same cause for the porosity of the paper allowed the gas
to escape quickly。
It is said that the name 〃balloon〃 was given to these paper craft
because they resembled in shape a large spherical vessel used in chemistry；
which was known by that name。 To the brothers Montgolfier belongs the
honour of having given the name to this type of aircraft； which； in the two
succeeding centuries； became so popular。
After nu