the angle of incidence that the aeroplane
darts downwardly.

In order to ascend, the tail, as shown in the second
diagram, is elevated so as to depress the rear
end, and now the sustaining surface shoots upwardly.

Suppose that in either of the positions 1 or 2,
thus described, the aviator should lose control of
the mechanism, or it should become deranged or
"stick," conditions which have existed in the history
of the art, what is there to prevent an accident?

In the first case, if there is room, the machine
will loop the loop, and in the second case the machine
will move upwardly until it is vertical, and
then, in all probability, as its propelling power is
not sufficient to hold it in that position, like a
helicopter, and having absolutely no wing supporting
surface when in that position, it will dart
down tail foremost.

A NON-CHANGING BODY.--We may contrast the
foregoing instances of flight with a machine having
the sustaining planes hinged to the body in
such a manner as to make the disposition of its
angles synchronous with the tail. In other words,
see how a machine acts that has the angle of flight
controllable by both planes,--that is, the sustaining
planes, as well as the tail.