, 1891-06-10
JUST HOW Man WILL FLY
NoT BY FLAPPING ARTIFICIAL WAC
BUT BY SOARING.


the A~cropitne Principic-AustraIia H..
Come Ncar to Solving the Problem
Man will yet learn how to ay Fro
fessor Langley, secretary Of the Smith
souiau institution, so declared in an al
dress delivered before the National
Academy Of Sciences This ought to
give much encouragement to thinkers
who hope that mankind will some dnv
sour domain in the element Of birds
just as It has already done, thanks to the
evolution Of submarine boats and diving
gear, in that Of fishes The distinguish
ed scientist referred to expressed conf.
dcuce that tho c~ourrivance Of the future
for aerial navigation would be on tho
kite principle.
The air possesses elements of buoy
ancy which have not been recognized
hitherto. There Is no truth in the popu-
lar conception that a body heavier than
the atmosphere caunot be suspended in
that medium without motion. A kite
Of sticks and paper is much heavier than
the fluid which it displaces, but it is sus-
tanned aloft. You can find an example
much more striking, however, in the
eagle or the frigatc bird, which, though
Du animal Of considerable weight, re-
mains poised in the sky upon extended
lintOns mOtionless for hours together, so
that a telescope may be trained on it.
Thousands of feet above the earth it is
sustained without movement of a feath-
er, though ia n rarcied atmosphere.
This is possible because the suspended
fowl has an instructive knowledge of the
way in which 10 utilize the air currents
for IFS support. When man has learned
how this can be done lie will be able to
dy. The most advanced investigators in
this subject reject the balloon aud all
other such lifting devices as impracti-
cable; n gas lighter than air can never
be safely confined within "A receptacle
that is not weighty, and the same objec-
ton applies to a acuum
~Ballooniug today is about where it
was when it was first invented, and in
the nature Of things it never get much
further Aluminium is light for "A metal,
but IL is several times too heavy to be
successfully utilized for such purposes.
Pray, what has become Of those alumni
mum trains Of cars that We're to be run
through the air from Chicago to New
York at sixty minutes the trip
LESSONS FROM BIRDS.
There is n school of flying machine in
ventors who may be designated ms the
'~luVpers, - inusmuch as their idea il to
sustain their -contrivances by the flap
ping Of birdlike wings. But they doubt
less forget that the best flyers among
birds do not support themselves by flap
ping. On the contrary, they only resort
to that performance when it is necessary
for "a start.
The eagle, If launching himself from
level ground. is obliged to take quite a
run first; then, Tapping his wings with
a violent muscular effort which he coult
not keep up for long, he gains a sufi
cient altitude to render it possible for
him to strike along the plane of an air
current which holds him up.
Floating with libratiug piuions from
one air current to another, he is lifted,
with an occasional broad sweep of his
powerful wings, to the upper aerial re-
gions, where he simply floats, opposing
to each movement Of the suspended
ether the gentle force necessary to main
tain him in his stationary position.
These principles which the eagle ap-
plies for purposes Of flight are perfectly
understood in the theory of mechanics
1t is only necessary to adapt them with
suitable apparatus in order to give to
human beings like powers. True, the
bird is lighter in proportion TO its size
than ia man. its bones are hollow and
filed with warm air from the lungs.
But the difference in this respect is
not very material, and it may easily be
compensated for by bigger wings. Pow
or to flap them is not what is required,
inasmuch as the start can be made from
a height; what is wanted is the knowl-
edge which inherited experience-'in-
stiuct"-has given the fowl as TO how TO
adapt the angles of the wings to the air
currents.
a PRACTICABLE MACHINE.
This is precisely what Professor Lang
ley has been experimenting with. What
he is attempting is to produce a machine
adapted to hotalou upon the air cur
rents like n kite. You can find a very
simple illustration of the principle he is
working on in the trick ,'one with play.
ing cards by the prestidigitator Herr
mann, who throws them from the stage
into the highest gallery of the biggest
hH'''f AA tic NlAtA DlAAt1t ilHlIlDlllnE
them "a after another among the
gods Of that select circle. How does
he duit3
Simply by skillfully utilizing the air
currents. The scrap of ~pastboard is
heavier than tho atmosphere, but, ju-
~diciously projected, it mounts to a
great height and distance with very lit
tie force. 1t would stay up, too, even if
thrown outdoors, supposiug that it pos
sassed the intelligence necessary to nc
commodate its surface to the winds.
What can be done in this way may be
accomplished on n larger scale. Lest
this proposition be disputed it will be
sufficient 10 refer to n flying machine
| patented in Australia It weighs alto
gether nineteen pounds, and its back
bone is a long copper cylinder two inches
in diameter, filled with compressed air.
The compressed air supplies power for a
small engine weighing ten pounds, at
the rear end Of the cylinder, which
works a fan propeller
To the backbone on either side is at
tached a great wing Of light material,
so hat the whole apparatus resembles a
big butterfly with two fans for a tail.
This cOutrivauce has been made to fly
horizontally 800 feet OF course it is
only a beginning, but all the same here
is the nearest approach to the practicable
flying machine Of the future thus far at
tanned w ashington Star.
TW ENTN DOLLAR GOLD PIECES,
Mrs. John Curtis of Peoria. ILL.,. writes:
Used one box of Usage Pills previous to
my second confinement; they worked like
a charm. Would pay $50 for a box