SHAPE OF SUPPORTING SURFACES.--When we examine
the prevailing type of supporting surfaces
we cannot fail to be impressed with one feature,
namely, the determination to insist on a broad
spread of plane surface, in imitation of the bird
with outstretched wings.

THE TROUBLE ARISING FROM OUTSTRETCHED
WINGS.--This form of construction is what brings
all the troubles in its train. The literature on
aviation is full of arguments on this subject, all
declaring that a wide spread is essential, because,
--birds fly that way.

These assertions are made notwithstanding the
fact that only a few years ago, in the great exhibit
of aeroplanes in Paris, many unique forms of machines
were shown, all of them capable of flying,
as proven by numerous experiments, and among
them were a half dozen types whose length fore
and aft were much greater than transversely, and
it was particularly noted that they had most wonderful
stability.

DENSITY OF THE ATMOSPHERE.--Experts declare
that the density of the atmosphere varies throughout,
--that it has spots here and there which are,
apparently, like holes, so that one side or the
other of the machine will, unaccountably, tilt, and