ther manufacturing
economies which reduce the cost of products.

To the high cost of aircraft their comparative fragility is added as
a reason for their unfitness for commercial uses. The engines cost
from $2000 to $5000 each, are very delicate and usually must be
taken out of the plane and overhauled after about 100 hours of
active service. The strain on them is prodigious for it is estimated
that the number of revolutions of an airplane's engine during an
hour's flight is equal to the number of revolutions of an
automobile's wheels during active service of a whole month.

It is believed that the superior lightness and durability of the
Liberty motor will obviate some of these objections to the
commercial availability of aircraft in times of peace. And it is
certain that with the cessation of the war, the retirement of the
governments of the world from the purchasing field and the reduction
of the demand for aircraft to such as are needed for pleasure and
industrial uses the prices which we have cited will be cut in half.
In such event what will be the future of aircraft; what their part
in the social and industrial organization of the world?

Ten or a dozen years ago Rudyard Kipling entertained the English
reading public of the world with a vivacious sketch of aerial
navigation in the year 2000 A.D. He used the license of a poet in
avoiding too precise descriptions of what is to come--dealing
rather with broad and picturesque generalizations. Now the year 2000
is still far enough away for pretty much anything to be invented,
and to become commonplace before that era arrives. Airships of the
sort Mr. Kipling pictured may by that period have come and
gone--have been relegated to the museums along with the
stage-coaches of yesterday and the locomotives of to-day. For that
matter before that millennial period shall arrive men may have
learned to dispense with material transportation altogether, and be
able to project their consciousness or even their astral bodies to
any desired point on psychic waves. If a poet is going to prophecy
he might as well be audacious and even revolutionary in his
predictions.

Mr. Kipling tried so hard to be reasonable that he made himself
recognizably wrong so far as the present tendency of aircraft
development would indicate. _With the Night Mail_, is the story of a
trip by night across the Atlantic from England to America. It is
made in a monster dirigible--though the present tendency