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 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.

PART II. AEROPLANES AND AIRMEN

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 small--the largest bird does not weigh much more than 20
pounds--but 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