Evening star. [volume] (Washington, D.C.) 1854-1972, 1907-04-07
Won LENDENFELD'S
INVESTIGATIONS
Into the Secret of the Flight of
Birds and Insects.
UNDER THE HODGKINS FUND
Aid Given by the Smithsonian In
stitution.
A FURTHER GRANT SIGNED
The Object Being to Discover the Ulti-
mate Extension of Mans Con-
troll Over the Air.
FURTHER GRANT SIGNED

| What is the secret of the flight of birds
| and insects? How much of this secret can
| be discovered and applied to the practical
! use of man? To answer these questions
| from thoroughly scientific observations is
| the ultimate object OF series of investi-
| cations by DR.. r. Won Lendenfeld of the
| Geological Institute. Prague, conducted
under grant from the Smithsonian Insti-
! tuition at Washington. Machines sustained
| by gases lighter than air have been found
unwieldy and mpracticable If man is
| ever to be carried through the atmosphere,
| it is now generally conceded it must
be by application of some scientific prin-
| ciple involved in the flight of birds and in
| sects.
! DR.. Won Lendenfeld's researches extend
| ing over a period of about six years have
| brought to light some vitality interesting
| facts so full Of possibilities that the secre-
! tary of the Smithsonian Institution has
just signed a further grant to enable the
| continuance of the work.
| The fund from which these grants are
| made. established in 1891 by MI Thomas
George Hodskins of Setauket n. Y,
| amounted to s2HtGO the income from one
| half of which is devoted to the increase
and diffusion of more exact knowledge in
! regard to the nature and properties of at
| mospheric air in cor rection with the well
| fare of man The object of this fund has
| been interpreted very broadly.
| Flight Of Birds and Insects.
| 10 discover the secret of the flight of
birds and insects is a purpose to which a
| portion of the income of the Hcdgkins
| fund has been devoted. 1t is an object touch
ing directly upon human progress. The
/ fund. therefore. lends material support to
! experiments which may mean the ultimate
| extension of mans control over ali element
| hitherto unconquered.
Tie present grant to DR.. Won Lendenfeld
| Is for the special purpose. as Secretary Wal
colt says. Ito make a thorough and exact
| investigation of the organs of flight of the
! best representative flyers of the insect or
der. In this investigation the wings of in
sects are to be considered in relation to
| the mechanics of flight as well as from a
purely morphological point of view" This
research follows naturally upon conclusions
which Dr. Won Lendenfeld has already
reached In work conducted personally and
under his direction for a number of years
TWO reports have been published by the
Smithsonian Institution and two more are
new in press to appear regular issues
of the Smithsonian miscellaneous coIlec-
lions.
Dr. Won Lendenfeld's first work under q
Smithsonian grant was performed in 1900
1t consisted mainly of general studies into
the structure and functions of the organs
or nylng creatures as preparation suitable
for researches into the actual mechanics
OF flight. Since then much of his time has
been taken up in personal laboratory IN
VeSugatlonS or in directing investigations of
his pupils in the university at Prague
The first set of experiments. completed
about three years ago, brought out some
curious facts concerning the wings of birds
In relation to the weight of their bodies.
1t was established beyond doubt that
some property of air enabled the larger
and heavier birds. such the albatross
IN f.,ir I,n;,.
comparatively much smaller wing surface
1T was worked out by analogy that given
the secret of control of motion man
weighing 200 pounds go kilograms) could
sail through the air with sustaining wing
surface of about three square yards O.
square mterS).
All Do Not Fly Alike.
But when DR.. Won Lendenfeld turned to
consider the actual mechanics of flight he
was contracted Immediately by the fact
that all birds by no means fly alike In
fact, there could hardly be established a
| mean similarity between all the varieties.
From the great soaring albatross and sea
eagle, which may sail for half an hour
without the culver of feather to the
whirring sparrow and the buzzing hum
| ming bird, which rely for support solely
upon the rapid movement of their wings
there is long line of flyers These two
extremes, the albatross and the humming
n
sects, also, he found could be classed in
like manner
Among both birds and insects, however,
the sailers were found not to be restricted
to the large creatures and the fappers to
the small On the contrary, there were
discovered creatures of all sizes in each
group. In the sailer class the lemon but
terfly was placed beside the stork and the
silver gull beside the dragon fly The flap
per class embraced flyers from the buzzard
and pheasant to the house fly and the
gnat. In this study of fight methodr-tAere-
fore. the question of size led to no con-
illusions.
Muscular power was an element to be
| considered. DR.. Won Lendenfeld was sat
isfied that the fiappers were gifted with
| much stronger muscles than the sailers
And merely for illustrative purposes since
he does not consider the feasibility of at
taching wings to man, he found that AL
though a human being could not imme-
diately develop enough muscle to join the
fapper class, he might well be able, If he
knew how, to soar at will.
All these conclusions hinged upon the in
teresting phenomenon that the increase in
| weight to be carried through the air is not
proportional to the necessary increase in
size of the supporting surface-that is the
larger the bird the smaller in proportion
are the wings. The results can be ex-
planned ''only upon the supposition that
the resistance of the air against moving
wings is not directly proportional to their
size, but that in enlarging the wings the
! resisting power of the air against them in
creaSeS in a greater ratio than their SUPER
| fetal dimensions. Knowing that the air
requires an appreciable time to yield to the
pressure of the moving wing and the larger
| the wing surface the greater the quantity
of air displaced and the greater the resist
ance of this compressed air to the subse-
quent wing stroke which must act upon it.
| 1t is evident that this conclusion is correct.
Principle Of Compressed Air.
Upon principle of compressed air, there
fore, may rest the ultimate solution of
mans flight above the earth.
At the same time that DIR. Won Lendenfeld
| was working out these facts. DR.. E. Mas
| cha, studying under his direction at the
institute was determining what magic
there might be in the feather structure
| Of birds Wings. His results show how
perfect for its purpose is the tapping of
| the feather quilts one over another The
| happy combination of strength and light
| ness so wildly pictured in this flexible
structure is a combination the value of
which is more widely realized in CONNER
| III On