towards the centre of the Earth with twice the force of that
other; if the mass be five times as great, then it will be attracted
with five times the force, and so on.

It is thus evident that the Earth must exert an overwhelming attractive
force on all bodies on or near its surface. Now, when man rises from the
ground in an aeroplane he is counter-acting this force by other forces.

A short time ago the writer saw a picture which illustrated in a very
striking manner man's struggle with Nature. Nature was represented as
a giant of immense stature and strength, standing on a globe with
outstretched arms, and in his hands were shackles of great size. Rising
gracefully from the earth, immediately in front of the giant, was
an airman seated in a modern flying-machine, and on his face was a
happy-go-lucky look as though he were delighting in the duel between him
and the giant. The artist had drawn the picture so skilfully that one
could imagine the huge, knotted fingers grasping the shackles were
itching to bring the airman within their clutch. The picture was
entitled "MAN 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.

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.