build
engines and screws of sufficient lightness and power to drive these
planes at sustaining speed. As long ago as 1893 a machine weighing 8,000
lbs. demonstrated its power both to lift itself from the ground and to
maintain a speed of from 30 to 40 miles per hour; but it came to grief
in an accidental free flight, owing to the inability of the operators to
balance and steer it properly. This inability to balance and steer still
confronts students of the flying problem, although nearly ten years have
passed. When this one feature has been worked out the age of flying
machines will have arrived, for all other difficulties are of minor
importance.

The person who merely watches the flight of a bird gathers the
impression that the bird has nothing to think of but the flapping
of its wings. As a matter of fact, this is a very small part of its
mental labour. Even to mention all the things the bird must constantly
keep in mind in order to fly securely through the air would take a
very considerable treatise. If I take a piece of paper, and after
placing it parallel with the ground, quickly let it fall, it will not
settle steadily down as a staid, sensible piece of paper ought to do,
but it insists on contravening every recognized rule of decorum,
turning over and darting hither and thither in the most erratic
manner, much after the style of an untrained horse. Yet this is the
style of steed that men must learn to manage before flying can become
an everyday sport. The bird has learned this art of equilibrium, and
learned it so thoroughly that its skill is not apparent to our sight.
We only learn to appreciate it when we try to imitate it. Now, there
are two ways of learning how to ride a fractious horse: one is to get
on him and learn by actual practice how each motion and trick may be
best met; the other is to sit on a fence and watch the beast awhile,
and then retire to the house and at leisure figure out the best way of
overcoming his jumps and kicks. The latter system is the safest; but
the former, on the whole, turns out the larger proportion of good
riders. It is very much the same in learning to ride a flying machine;
if you are looking for perfect safety you will do well to sit on a
fence and watch the birds; but if you really wish to learn you must
mount a machine and become acquainted with its tricks by actual trial.

* * * * *

My own active interest in aeronautical problems date