the mastery of the air(操纵空气)-第12节
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systematic bombardment。
At the time of writing； Germany is beginning to suffer some of the
annoyances she is so ready to inflict upon others。 The recently constituted
Air Ministry have just published figures relating to the air raids into
Germany from December 1； 1917； to February 19； 1918 inclusive。 During
these eleven weeks no fewer than thirty…five raids have taken place upon a
variety of towns； railways； works； and barracks。 In the list figure such
important towns as Mannheim （pop。 20；000） and Metz （pop。 100；000）。
The average weight of bombs dropped at each raid works out about 1000
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lbs。 This welcome official report is but one of many signs which point the
way to the growing supremacy of the Allies in the air。
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THE MASTERY OF THE AIR
PART II AEROPLANES AND
AIRMEN
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CHAPTER XIV Early Attempts in Aviation
The desire to fly is no new growth in humanity。 For countless years
men have longed to emulate the birds〃To soar upward and glide； free as
a bird； over smiling fields； leafy woods； and mirror…like lakes；〃 as a great
pioneer of aviation said。 Great scholars and thinkers of old； such as Horace；
Homer； Pindar； Tasso； and all the glorious line； dreamt of flight； but it has
been left for the present century to see those dreams fulfilled。
Early writers of the fourth century saw the possibility of aerial
navigation； but those who tried to put their theories in practice were beset
by so many difficulties that they rarely succeeded in leaving the ground。
Most of the early pioneers of aviation believed that if a man wanted to
fly he must provide himself with a pair of wings similar to those of a large
bird。 The story goes that a certain abbot told King James IV of Scotland
that he would fly from Stirling Castle to Paris。 He made for himself
powerful wings of eagles' feathers； which he fixed to his body and
launched himself into the air。 As might be expected； he fell and broke his
legs。
But although the muscles of man are of insufficient strength to bear
him in the air； it has been found possible； by using a motor engine； to give
to man the power of flight which his natural weakness denied him。
Scientists estimate that to raise a man of about 12 stone in the air and
enable him to fly there would be required an immense pair of wings over
20 feet in span。 In comparison with the weight of a man a bird's weight is
remarkably smallthe largest bird does not weigh much more than 20
poundsbut its wing muscles are infinitely stronger in proportion than the
shoulder and arm muscles of a man。
As we shall see in a succeeding chapter； the 〃wing〃 theory was
persevered with for many years some two or three centuries ago； and later
on it was of much use in providing data for the gradual development of the
modern aeroplane。
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CHAPTER XV A Pioneer in Aviation
Hitherto we have traced the gradual development of the balloon right
from the early days of aeronautics； when the brothers Montgolfier
constructed their hot…air balloon； down to the most modern dirigible。 It is
now our purpose； in this and subsequent chapters； to follow the course of
the pioneers of aviation。
It must not be supposed that the invention of the steerable balloon was
greatly in advance of that of the heavier…than…air machine。 Indeed；
developments in both the dirigible airship and the aeroplane have taken
place side by side。 In some cases men like Santos Dumont have given
earnest attention to both forms of air…craft； and produced practical results
with both。 Thus； after the famous Brazilian aeronaut had won the Deutsch
prize for a flight in an air…ship round the Eiffel tower； he immediately set
to work to construct an aeroplane which he subsequently piloted at
Bagatelle and was awarded the first 〃Deutsch prize〃 for aviation。
It is generally agreed that the undoubted inventor of the aeroplane；
practically in the form in which it now appears； was an English engineer；
Sir George Cayley。 Just over a hundred years ago this clever Englishman
worked out complete plans for an aeroplane； which in many vital respects
embodied the principal parts of the monoplane as it exists to…day。
There were wings which were inclined so that they formed a lifting
plane； moreover； the wings were curved； or 〃cambered〃； similar to the
wing of a bird； and； as we shall see in a later chapter； this curve is one of
the salient features of the plane of a modern heavier…than…air machine。 Sir
George also advocated the screw propeller worked by some form of
〃explosion〃 motor； which at that time had not arrived。 Indeed； if there had
been a motor available it is quite possible that England would have led the
way in aviation。 But； unfortunately； owing to the absence of a powerful
motor engine； Sir George's ideas could not be practically carried out till
nearly a century later； and then Englishmen were forestalled by the Wright
brothers； of America； as well as by several French inventors。
The distinguished French writer； Alphonse Berget； in his book； The
Conquest of the Air； pays a striking tribute to our English inventor； and
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this； coming from a gentleman who is writing from a French point of view；
makes the praise of great value。 In alluding to Sir George； M。 Berget says：
〃The inventor； the incontestable forerunner of aviation； was an
Englishman； Sir George Cayley； and it was in 1809 that he described his
project in detail in Nicholson's Journal。 。 。 。 His idea embodied
'everything'the wings forming an oblique sail； the empennage； the
spindle forms to diminish resistance； the screw…propeller； the 'explosion'
motor； 。 。 。 he even described a means of securing automatic stability。 Is
not all that marvellous； and does it not constitute a complete specification
for everything in aviation？
〃Thus it is necessary to inscribe the name of Sir George Cayley in
letters of gold； in the first page of the aeroplane's history。 Besides； the
learned Englishman did not confine himself to 'drawing…paper'： he built
the first apparatus （without a motor） which gave him results highly
promising。 Then he built a second machine； this time with a motor； but
unfortunately during the trials it was smashed to pieces。〃
But were these ideas of any practical value？ How is it that he did not
succeed in flying； if he had most of the component parts of an aeroplane as
we know it to…day？
The answer to the second question is that Sir George did not fly；
simply because there was no light petrol motor in existence； the crude
motors in use were far too heavy； in proportion to the power developed；
for service in a flying machine。 It was recognized； not only by Sir George；
but by many other English engineers in the first half of the nineteenth
century； that as soon as a sufficiently powerful and light engine did appear；
then half the battle of the conquest of the air would be won。
But his prophetic voice was of the utmost assistance to such inventors
as Santos Dumont； the Wright brothers； M。 Bleriot； and others now world…
famed。 It is quite safe to assume that they gave serious attention to the
views held by Sir George； which were given to the world at large in a
number of highly…interest… ing lectures and magazine articles。 〃Ideas〃 are
the very foundation…stones of inventionif we may be allowed the figure
of speechand Englishmen are proud； and r
