aeroplanes-第6部分

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wherein　mechanical　flight　is　supposed　to　be　analogous

to　bird　flight。



SPEED　AND　SURFACE。Birds　which　poise　in　the

air；　like　the　humming　bird；　do　so　because　they

beat　their　wings　with　great　rapidity。　Those

which　soar；　as　stated；　can　do　so　only　by　moving

through　the　atmosphere　rapidly；　or　by　having　a

large　wing　spread　relative　to　the　weight。　It　will

thus　be　seen　that　speed　and　surface　become　the

controlling　factors　in　flight；　and　that　while　the

latter　may　be　entirely　eliminated　from　the　problem；

speed　is　absolutely　necessary　under　any　and

all　conditions。



By　speed　in　this　connection　is　not　meant　high

velocity；　but　that　a　movement；　produced　by　power

expressed　in　some　form；　is　the　sole　and　most　necessary

requisite　to　movement　through　the　air　with

all　heavier…than…air　machines。



If　sufficient　power　can　be　applied　to　an　aeroplane；

surface　is　of　no　consequence；　shape　need

not　be　considered；　and　any　sort　of　contrivance

will　move　through　the　air　horizontally。



CONTROL　OF　THE　DIRECTION　OF　FLIGHT。But　the

control　of　such　a　body；　when　propelled　through

space　by　force　alone；　is　a　different　matter。　To

change　the　machine　from　a　straight　path　to　a

curved　one；　means　that　it　must　be　acted　upon　by

some　external　force。



We　have　explained　that　power　is　something

which　is　inherent　in　the　thing　itself。　Now；　in　order

that　there　may　be　a　change　imparted　to　a

moving　mass；　advantage　must　be　taken　of　the　medium

through　which　it　moves；the　atmosphere。



VERTICAL　CONTROL　PLANES。If　vertically…arranged

planes　are　provided；　either　fore　or　aft　of

the　machine；　or　at　both　ends；　the　angles　of　incidence

may　be　such　as　to　cause　the　machine　to

turn　from　its　straight　course。



In　practice；　therefore；　since　it　is　difficult　to　supply

sufficient　power　to　a　machine　to　keep　it　in　motion

horizontally；　at　all　times；　aeroplanes　are　provided

with　supporting　surfaces；　and　this　aid　in

holding　it　up　grows　less　and　less　as　its　speed　increases。



But；　however　strong　the　power；　or　great　the

speed；　its　control　from　side　to　side　is　not　dependent

on　the　power　of　the　engine；　or　the　speed

at　which　it　travels　through　the　air。



Here　the　size　of　the　vertical　planes；　and　their

angles；　are　the　only　factors　to　be　considered；　and

these　questions　will　be　considered　in　their　proper

places。









CHAPTER　III



THE　FORM　OR　SHAPE　OF　FLYING　MACHINES





EVERY　investigator；　experimenter；　and　scientist；

who　has　given　the　subject　of　flight　study；　proceeds

on　the　theory　that　in　order　to　fly　man　must

copy　nature；　and　make　the　machine　similar　to　the

type　so　provided。



THE　THEORY　OF　COPYING　NATURE。If　such　is　the

case　then　it　is　pertinent　to　inquire　which　bird　is

the　proper　example　to　use　for　mechanical　flight。

We　have　shown　that　they　differ　so　radically　in

every　essential；　that　what　would　be　correct　in　one

thing　would　be　entirely　wrong　in　another。



The　bi…plane　is　certainly　not　a　true　copy。　The

only　thing　in　the　Wright　machine　which　in　any

way　resembles　the　bird's　wing；　is　the　rounded　end

of　the　planes；　and　judging　from　other　machines；

which　have　square　ends；　this　slight　similarity　does

not　contribute　to　its　stability　or　otherwise　help

the　structure。



The　monoplane；　which　is　much　nearer　the　bird

type；　has　also　sounded　wing　ends；　made　not　so

much　for　the　purpose　of　imitating　the　wing　of　the

bird；　as　for　structural　reasons。



HULLS　OF　VESSELS。If　some　marine　architect

should　come　forward　and　assert　that　he　intended

to　follow　nature　by　making　a　boat　with　a　hull　of

the　shape　or　outline　of　a　duck；　or　other　swimming

fowl；　he　would　be　laughed　at；　and　justly　so；　because

the　lines　of　vessels　which　are　most　efficient

are　not　made　like　those　of　a　duck　or　other　swimming

creatures。



MAN　DOES　NOT　COPY　NATURE。Look　about　you；

and　see　how　many　mechanical　devices　follow　the

forms　laid　down　by　nature；　or　in　what　respect

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