With our lines resting on the sea on the northern
and southern coasts of Europe, there is no possibility of finding a way round in the old-fashioned manner. The density of modern systems of defence, again, seems to have prohibited a way through ; even when there is a local rout, cavalry cannot be employed to spread disaster. But the way over, the way through the air to the back of the enemy's lines, is always open to the flying men who get command of the air. If we can fill the air with British, French, Italian, and American aeroplanes to such an extent that no German aeroplane can take the air or survive if it rises from the ground, we shall have deprived our enemy not only of his sight but of one of, his limbs. Through being deprived of the power of observation, his artillery would become ineffective ; and if our airmen operating behind his lines had the air wholly free for their operations, they could take the place of cavalry, and indeed exceed the dreams of the most enthusiastic cavalry leader who ever lived. An aeroplane is a horse that can gallop at a hundred miles an hour with a machine- gun on his back.
