The record-union., 1896-05-24
THE PROBLEM OF AERIAL NAvI-
CATION.

It is very confidently and loudly an
nounced at the East by the metropon-
tan press that the problem of navigating
the air has been solved by Professor S.
P. Langley OF the Smithsonian Insti-
tion, Washington. Something over a
fortnight ago he sent up q. model Of
machine he has invented, and it rose 200
feet in the air and Travelled as directed
for something over half a mile. It's
descent was due to the fuel giving out.
1t was restocked and again went up
and made a second trip of about the
same distance, and then gently came to
the ground
Professor Andrew Graham Bell Of tel
ephone prominence was one Of the wit
neSses to the experiment, and in a
rather 1orid account Of what he saw he
declares that the event was one of great
historical Importance. He describes the
machine Of Professor Langley as of steel
frame, with immense planes of fiat sur
faces of canvas, which support it as the
wings of a bird sustain the body. a
small engine operates machinery that
gives the air ship a broad spiral motion
as it sails gracefully in the air. Two
propellors then give il momentum, and
IT proceeds through the air until the
steam supply gives out
The model is 10 feet long and weighs
but twenty-five pounds. The PROPOSE
ton is to construct a machine eighty
feet long, with q properly adapted en-
gine 10 condense the steam, and for
fuel to use condensed gas, or liquid fuel
only. The calculation Is that such a
machine can make eighteen miles an
hour. and carry a number of passengers,
four horsepower Copeland engine
only being needed, that will occupy but
ten inches of floor space and weigh but
twenty-seven pounds.
The claim OF the Smithsonian profess
sor is that as he increases the speed he
Will increase the carrying capacity to
given limit, and that as the density of
the air is sufficient to engage the propel-
ler blades, the speed depends only upon
the rapidity of the revolutions of the
propellers. He believes, therefore, that
his new ship can attain a speed Of 100
miles an hour with ease and safety. Pro
eesSor Bell says:
The theory of the aerodrorne is wholly
different from that OF the balloon 1t
does not aim to float by reason of being
lighter than the air. Professor Lang
Iey's machine weighs about 1000 times
as much as the air which supports it.
1t relies upon the air currents, as does
a soaring bird. It's principle is derived
from the suggestions offered by birds Of
the vulture type. There is no better ex-
ample OF soaring than the vulture,
which though a large and heavy animal,
viii remain for a whole day in the air
without single wingbeat, simply op-
posing its wings to the air currents.
Most people have seen the magician
throw playing cards from the stage Of
a theater into the third and fourth gal
lerieS. This is ali Illustration of the sus-
tanning power afforded by the air TO
thin planes moving swiftly through it.
The same principle applies to the aero
drome. Suppose that such an air ship
is on its way from New York to Chicago
at a speed OF fifty miles AN hour. the day
being perfectly calm. OF course this
means a fifty mile current Of air in
effect. 1t opposes the progress Of the
vessel very slightly, because the latter
presents merely the edge of its plane to
the breeze. The captain at the helm
inclines the planes upward a trifle at
the front, so that the powerful air cur
rent is made to exercise its lifting power
and keep the craft afioat. But which
ever way the current comes. the planes
are governed accordingly. The wing
planes on either side are slanted slightly
upward, so that any tendency TO tilt
will develop greater pressure in that
direction and thus restore equilibrium.
People commonly think Of flight in
the air as implying an ascent to great
nights, but for that there is no neces-
sity All that is required for practical
purposes is that the aerodrome shall
travel at a level high enough to be
clear of houses and trees. The start
must be made from a hight Not the