and winning their freedom in a new
element. The advance which the Allies or the Germans made over each
other in scientific aerial development was a joint advance over the
restrictions of gravitation.

This, indeed, apart from the spread of democracy and internationalism,
may well stand out in history as the war's richest heritage. Problems
which had been considered insoluble were solved. The casting aside of
all conventions, all restrictive habits of thought, all selfishnesses,
and the focusing of the highest scientific ability in a struggle which
might mean the life or death of the nation, had brought as a
by-product a development beyond our wildest fancies.

Aerial operations in any future war, however, will have at once a
problem which has only recently and in very much smaller degree
confronted the navy, namely, the assurance of attack not only on the
front, in the rear, and on both flanks, but from above and below as
well. Recently the navy has had to face that problem--submarines
operating below and airplanes above; but the problem of attack upon a
ship is not so serious as upon an airplane.

Already, in order to meet this danger of attack from every possible
direction, a most complete strategy and system of formations have been
worked out. In this way the various types of planes operate in
different air strata according to their missions, the upper planes
echelon somewhat behind those below on the order of a flight of steps
facing the enemy. This system provides a quick method of reception of
an attack and the assurance of quick support, no matter where the
attack may come. Obviously there would be nothing in all of warfare on
either land or sea comparable to a collision between two such aerial
fleets. The speed of the lighter planes, quick, life-taking duels in
several different strata at once, would provide a clash of action,
speed, and skill far more beautiful and yet in many ways far more
terrible than anything ever recorded in the history of war.

Fleets of the skies--who shall attempt at this day of the infancy of
the science to limit their scope? Aerial battle-planes of colossal
size and power are as certain to come in time, and in not a very long
time, as the dreadnought of to-day was certain to follow the first
armored ship of only a half-century ago. Never yet has man opened up a
new avenue of war that he has not pursued it relentlessly to its final
conclusion. It is certain that he will not fail to