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aeroplanes-第7节

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man uses the types which nature provides in devising

the many inventions which ingenuity has

brought forth。



PRINCIPLES ESSENTIAL; NOT FORMS。It is essential

that man shall follow nature's laws。 He cannot

evade the principles on which the operations

of mechanism depend; but in doing so he has; in

nearly every instance; departed from the form

which nature has suggested; and made the machine

irrespective of nature's type。



Let us consider some of these striking differences

to illustrate this fact。 Originally pins were

stuck upon a paper web by hand; and placed in

rows; equidistant from each other。 This necessitates

the cooperative function of the fingers and

the eye。 An expert pin sticker could thus assemble

from four to five thousand pins a day。



The first mechanical pinsticker placed over

500;000 pins a day on the web; rejecting every bent

or headless pin; and did the work with greater

accuracy than it was possible to do it by hand。

There was not the suggestion of an eye; or a finger

in the entire machine; to show that nature furnished

the type。



NATURE NOT THE GUIDE AS TO FORMS。Nature

does not furnish a wheel in any of its mechanical

expressions。 If man followed nature's form

in the building of the locomotive; it would move

along on four legs like an elephant。 Curiously

enough; one of the first road wagons had 〃push

legs;〃an instance where the mechanic tried to

copy nature;and failed。



THE PROPELLER TYPE。The well known propeller

is a type of wheel which has no prototype in

nature。 It is maintained that the tail of a fish

in its movement suggested the propeller; but the

latter is a long departure from it。



The Venetian rower; who stands at the stern;

and with a long…bladed oar; fulcrumed to the

boat's extremity; in making his graceful lateral

oscillations; simulates the propelling motion of

the tail in an absolutely perfect manner; but it is

not a propeller; by any means comparable to the

kind mounted on a shaft; and revoluble。



How much more efficient are the spirally…formed

blades of the propeller than any wing or fin movement;

in air or sea。 There is no comparison between

the two forms in utility or value。



Again; the connecting points of the arms and

legs with the trunk of a human body afford the

most perfect types of universal joints which nature

has produced。 The man…made universal

joint has a wider range of movement; possesses

greater strength; and is more perfect mechanically。

A universal joint is a piece of mechanism

between two elements; which enables them to be

turned; or moved; at any angle relative to each

other。



But why multiply these instances。 Like samples

will be found on every hand; and in all directions;

and man; the greatest of all of nature's

products; while imperfect in himself; is improving

and adapting the things he sees about him。



WHY SPECIALLY…DESIGNED FORMS IMPROVE NATURAL

STRUCTURES。The reason for this is; primarily;

that the inventor must design the article

for its special work; and in doing so makes it better

adapted to do that particular thing。 The

hands and fingers can do a multiplicity of things;

but it cannot do any particular work with the facility

or the degree of perfection that is possible

with the machine made for that purpose。



The hands and fingers will bind a sheaf of

wheat; but it cannot compete with the special machine

made for that purpose。 On the other hand

the binder has no capacity to do anything else than

what it was specially made for。



In applying the same sort of reasoning to the

building of flying machines we must be led to the

conclusion that the inventor can; and will; eventually;

bring out a form which is as far superior to

the form which nature has taught us to use as

the wonderful machines we see all about us are

superior to carry out the special work they were

designed to do。



On land; man has shown this superiority over

matter; and so on the sea。 Singularly; the submarines;

which go beneath the sea; are very far

from that perfected state which have been attained

by vessels sailing on the surface; and while

the means of transportation on land are arriving

at points where the developments are swift and

remarkable; the space above the earth has not yet

been conquered; but is going through that same

period of development which precedes the production

of the true form itself。



MECHANISM DEVOID OF INTELLIGENCE。The great

error; however; in seeking to copy nature's form

in a flying machine is; that we cannot invest the

mechanism with that which the bird has; namely;

a guiding intelligence to direct it instinctively; as

the flying creature does。



A MACHINE MUST HAVE A SUBSTITUTE FOR INTELLIGENCE。

Such being the case it must be endowed

with something which is a substitute。 A

bird is a supple; pliant organism; a machine is a

rigid structure。 One is capable of being directed

by a mind which is a part of the thing itself; while

the other must depend on an intelligence which is

separate from it; and not responsive in feeling or

movement。



For the foregoing reasons success can never

be attained until some structural form is devised

which will consider the flying machine independently

of the prototypes pointed out as the correct

things to follow。 It does not; necessarily; have to

be unlike the bird form; but we do know that the

present structures have been made and insisted

upon blindly; because of this wrong insistence on

forms。



STUDY OF BIRD FLIGHT USELESS。The study of

the flight of birds has never been of any special

value to the art。 Volumes have been written on

the subject。 The Seventh Duke of Argyle; and

later; Pettigrew; an Englishman; contributed a

vast amount of written matter on the subject of

bird flight; in which it was sought to show that

soaring birds did not exert any power in flying。



Writers and experimenters do not agree on the

question of the propulsive power; or on the form

or shape of the wing which is most effective; or

in the matter of the relation of surface to weight;

nor do they agree in any particular as to the effect

and action of matter in the soaring principle。



Only a small percentage of flying creatures use

motionless wings as in soaring。 By far; the

greater majority use beating wings; a method of

translation in air which has not met with success

in any attempts on the part of the inventor。



Nevertheless; experimenting has proceeded on

lines which seek to recognize nature's form only;

while avoiding the best known and most persistent

type。



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

sometimes the entire machine will suddenly drop

for many feet; while in flight。



ELASTICITY OF THE AIR。Air is the most elastic

substance known。 The particles constituting it

are constantly in motion。 When heat or cold penetrate

the mass it does so; in a general way; so as

to permeate the entire body; but the conductivity

of the atmospheric gases is such that the heat

does not reach all parts at the same time。



AIR HOLES。The result is that varying strata

of heat and cold seem to be superposed; and also

distributed along the route taken by a machine;

causing air currents which vary in direction and

intensity。 When; therefore; a rapidly…moving

machine passes through an atmosphere so disturbed;

the surfaces of the planes strike a mass of

air moving; we may say; first toward the plane;

and the next instant the current is reversed; and

the machine drops; because its support is temporarily

gone; and the aviator experiences the sensation

of going into a 〃hole。〃



RESPONSIBILITY FOR ACCIDENTS。These so…called

〃holes〃 are responsible for many accidents。 T

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