the age of invention-第26章

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e　of　the　wings；　the　disposition　of　the　wings　themselves；　the　size　of　the　propellers；　the　inclination　and　number　of　the　blades；　and　a　great　number　of　other　details；　presented　themselves　for　examination。〃

By　1891　Langley　had　a　model　light　enough　to　fly；　but　proper　balancing　had　not　been　attained。　He　set　himself　anew　to　find　the　practical　conditions　of　equilibrium　and　of　horizontal　flight。　His　experiments　convinced　him　that　〃mechanical　sustenation　of　heavy　bodies　in　the　air；　combined　with　very　great　speeds；　is　not　only　possible；　but　within　the　reach　of　mechanical　means　we　actually　possess。〃

After　many　experiments　with　new　models　Langley　at　length　fashioned　a　steam…driven　machine　which　would　fly　horizontally。　It　weighed　about　thirty　pounds；　it　was　some　sixteen　feet　in　length；　with　two　sets　of　wings；　the　pair　in　front　measuring　forty　feet　from　tip　to　tip。　On　May　6；　1896；　this　model　was　launched　over　the　Potomac　River。　It　flew　half　a　mile　in　a　minute　and　a　half。　When　its　fuel　and　water　gave　out；　it　descended　gently　to　the　river's　surface。　In　November　Langley　launched　another　model　which　flew　for　three…quarters　of　a　mile　at　a　speed　of　thirty　miles　an　hour。　These　tests　demonstrated　the　practicability　of　artificial　flight。

The　Spanish…American　War　found　the　military　observation　balloon　doing　the　limited　work　which　it　had　done　ever　since　the　days　of　Franklin。　President　McKinley　was　keenly　interested　in　Langley's　design　to　build　a　power…driven　flying　machine　which　would　have　innumerable　advantages　over　the　balloon。　The　Government　provided　the　funds　and　Langley　took　up　the　problem　of　a　flying　machine　large　enough　to　carry　a　man。　His　initial　difficulty　was　the　engine。　It　was　plain　at　once　that　new　principles　of　engine　construction　must　be　adopted　before　a　motor　could　be　designed　of　high　power　yet　light　enough　to　be　borne　in　the　slender　body　of　an　airplane。　The　internal　combustion　engine　had　now　come　into　use。　Langley　went　to　Europe　in　1900；　seeking　his　motor；　only　to　be　told　that　what　he　sought　was　impossible。

His　assistant；　Charles　M。　Manly；　meanwhile　found　a　builder　of　engines　in　America　who　was　willing　to　make　the　attempt。　But；　after　two　years　of　waiting　for　it；　the　engine　proved　a　failure。　Manly　then　had　the　several　parts　of　it；　which　he　deemed　hopeful；　transported　to　Washington；　and　there　at　the　Smithsonian　Institution　he　labored　and　experimented　until　he　evolved　a　light　and　powerful　gasoline　motor。　In　October；　1903；　the　test　was　made；　with　Manly　aboard　of　the　machine。　The　failure　which　resulted　was　due　solely　to　the　clumsy　launching　apparatus。　The　airplane　was　damaged　as　it　rushed　forward　before　beginning　to　soar；　and；　as　it　rose；　it　turned　over　and　plunged　into　the　river。　The　loyal　and　enthusiastic　Manly；　who　was　fortunately　a　good　diver　and　swimmer；　hastily　dried　himself　and　gave　out　a　reassuring　statement　to　the　representatives　of　the　press　and　to　the　officers　of　the　Board　of　Ordnance　gathered　to　witness　the　flight。

A　second　failure　in　December　convinced　spectators　that　man　was　never　intended　to　fly。　The　newspapers　let　loose　such　a　storm　of　ridicule　upon　Langley　and　his　machine；　with　charges　as　to　the　waste　of　public　funds；　that　the　Government　refused　to　assist　him　further。　Langley；　at　that　time　sixty…nine　years　of　age；　took　this　defeat　so　keenly　to　heart　that　it　hastened　his　death；　which　occurred　three　years　later。　〃Failure　in　the　aerodrome　itself；〃　he　wrote；　〃or　its　engines　there　has　been　none；　and　it　is　believed　that　it　is　at　the　moment　of　success；　and　when　the　engineering　problems　have　been　solved；　that　a　lack　of　means　has　prevented　a　continuance　of　the　work。〃


It　was　truly　〃at　the　moment　of　success〃　that　Langley's　work　was　stopped。　On　December　17；　1903；　the　Wright　brothers　made　the　first　successful　experiment　in　which　a　machine　carrying　a　man　rose　by　its　own　power；　flew　naturally　and　at　even　speed；　and　descended　without　damage。　These　brothers；　Wilbur　and　Orville；　who　at　last　opened　the　long　besieged　lanes　of　the　air；　were　born　in　Dayton；　Ohio。　Their　father；　a　clergyman　and　later　a　bishop；　spent　his　leisure　in　scientific　reading　and　in　the　invention　of　a　typewriter　which；　however；　he　never　perfected。　He　inspired　an　interest　in　scientific　principles　in　his　boys'　minds　by　giving　them　toys　which　would　stimulate　their　curiosity。　One　of　these　toys　was　a　helicopter；　or　Cayley's　Top；　which　would　rise　and　flutter　awhile　in　the　air。

After　several　helicopters　of　their　own；　the　brothers　made　original　models　of　kites；　and　Orville；　the　younger；　attained　an　exceptional　skill　in　flying　them。　Presently　Orville　and　Wilbur　were　making　their　own　bicycles　and　astonishing　their　neighbors　by　public　appearances　on　a　specially　designed　tandem。　The　first　accounts　which　they　read　of　experiments　with　flying　machines　turned　their　inventive　genius　into　the　new　field。　In　particular　the　newspaper　accounts　at　that　time　of　Otto　Lilienthal's　exhibitions　with　his　glider　stirred　their　interest　and　set　them　on　to　search　the　libraries　for　literature　on　the　subject　of　flying。　As　they　read　of　the　work　of　Langley　and　others　they　concluded　that　the　secret　of　flying　could　not　be　mastered　theoretically　in　a　laboratory；　it　must　be　learned　in　the　air。　It　struck　these　young　men；　trained　by　necessity　to　count　pennies　at　their　full　value；　as　〃wasteful　extravagance〃　to　mount　delicate　and　costly　machinery　on　wings　which　no　one　knew　how　to　manage。　They　turned　from　the　records　of　other　inventors'　models　to　study　the　one　perfect　model；　the　bird。　Said　Wilbur　Wright；　speaking　before　the　Society　of　Western　Engineers；　at　Chicago：

〃The　bird's　wings　are　undoubtedly　very　well　designed　indeed；　but　it　is　not　any　extraordinary　efficiency　that　strikes　with　astonishment；　but　rather　the　marvelous　skill　with　which　they　are　used。　It　is　true　that　I　have　seen　birds　perform　soaring　feats　of　almost　incredible　nature　in　positions　where　it　was　not　possible　to　measure　the　speed　and　trend　of　the　wind；　but　whenever　it　was　possible　to　determine　by　actual　measurements　the　conditions　under　which　the　soaring　was　performed　it　was　easy　to　account　for　it　on　the　basis　of　the　results　obtained　with　artificial　wings。　The　soaring　problem　is　apparently　not　so　much　one　of　better　wings　as　of　better　operators。〃*

*　Cited　in　Turner；　〃The　Romance　of　Aeronautics〃。


When　the　Wrights　determined　to　fly；　two　problems　which　had　beset　earlier　experimenters　had　been　partially　solved。　Experience　had　brought　out　certain　facts　regarding　the　wings；　and　invention　had　supplied　an　engine。　But　the　laws　governing　the　balancing　and　steering　of　the　machine　were　unknown。　The　way　of　a　man　in　the　air　had　yet　to　be　discovered。

The　starting　point　of　their　theory　of　flight　seems　to　have　been　that　man　was　endowed　with　an　intelligence　at　least　equal　to　that　of　the　bird；　and；　that　with　practice　he　could　learn　to　balance　himself　in　the　air　as　naturally　and　instinctively　as　on　the　ground。　He　must　and　could　be；　like　the　bird；　the　controlling　intelligence　of　his　machine。　To　quote　Wilbur　Wright　again：

〃It　seemed　to　us　that　the　main　reason　why　the　problem　had　remained　so　long　unsolved　was　that　no　one　had　been　able　to　obtain　any　adequate　practice。　Lilienthal　in　five　years　of　time　had　spent　only　five　hours　in　actual　gliding　through　the　air。　The　wonder　was　not　that　he　had　done　so　little　but　that　he　had　accomplished　so　much。　It　would　not　be　considered　at　all　safe　for　a　bicycle　rider　to　attempt　to　ride　through　a　crowded　city　street　after　only　five　hours'　practice　spread　out　in　bits　of　ten　seconds　each　over　a　period　of　five　years；　yet　Lilienthal　with　his　brief　practice　was　remarkably　successful　in　meeting　the　fluctuations　and　eddies　of　wind　gusts。　We　thought　that　if　some　method　could　be　found　by　which　it　would　be　possible　to　practice　by　the　hour　instead　of　by　the　second；　there　would　be　a　hope　of　advancing　the　solution　of　a　very　difficult　problem。〃

The　brothers　found　that　winds　of　the　velocity　they　desired　for　their　experiments　were　common　on　the　coast　of　North　Carolina。　They　pitched　their　camp　at　Kitty　Hawk　in　October；　1900；　and　made　a　brief　and　successful　trial　of　their　gliding　machine。　Next　year；　they　returned　with　a　much　larger　machine；　and　in　1902　they　continued　their　experiments　with　a　model　still　further　improved　from　their　first　design。　Having　tested　their　theories　and　become　convinced　that　they　were　definitely　on　the　right　track；　they　were　no　longer　satisfied　merely　to　glide。　They　set　about　constructing　a　power　machine。　Here　a　new　problem　met　them。　They　had　decided　on　two　screw　propellers　rotating　in　opposite　directions　on　the　principle　of　wings　in　flight；　but　the　proper　diameter；　pitch；　and　area　of　blade　were　not　easily　arrived　at。

On　December　17；　1903；　the　first　Wright　biplane　was　ready　to　navigate　the　air　and　made　four　brief　successful　flights。　Subsequent　flights　in　1904　demonstrated　that　the　problem　of　equilibrium　had　not　been　fully　solved；　but　the　experiments　of　1905　banished　this　difficulty。

The　responsibility　which　the　Wrights　placed　upon　the　aviator　for　maintaining　his　equilibrium；　and　the　tailless　design　of　their　machine；　caused　much　headshaking　among　foreign　flying　men　when　Wilbur　Wright　appeared　at　the　great　aviation　meet　in　France　in　1908。　But　he　won　the　Michelin　Prize　of　eight　hundred　pounds　by　beating　previous　records　for　speed　and　for　the　time　which　any　machine　had　remained　in　the　air。　He　gave　exhibitions　also　in　Germany　and　Italy　and　instructed　Italian　army　officers　in　the　flying　of　Wright　machines。　At　this　time　Orville　was　giving　similar　demonstrations　in　America。　Transverse　control；　the　warping　device　invented　by　the　Wright　brothers　for　the　preservation　of　lateral　balance　and　for　artificial　inclination　in　making　turns；　has　been　employed　in　a　similar　or　modified　form　in　most　airplanes　since　constructed。

There　was　no　〃mine〃　or　〃thine〃　in　the　diction　of　the　Wright　brothers；　only　〃we〃　and　〃ours。〃　They　were　joint　inventors；　they　shared　their　fame　equally　and　all　their　honors　and　prizes　also　until　the　death　of　Wilbur　in　1912。　They　were　the　first　inventors　to　make　the　ancient　dream　of　flying　man　a　reality　and　to　demonstrate　that　reality　to　the　practical　world。


When　the　NC　flying　boats　of　the　United　States　navy　lined　up　at　Trepassey　in　May；　1919；　for　their　Atlantic　venture；　and　the　press　was　full　of　pictures　of　them；　how　many　hasty　readers；　eager　only　for　news　of　the　start；　stopped　to　think　what　the　initials　NC　stood　for？

The　seaplane　is　the　chief　contribution　of　Glenn　Hammond　Curtiss　to　aviation；　and　the　Navy　Curtiss　Number　Four；　which　made　the　first　transatlantic　flight　in　history；　was　designed　by　him。　The　spirit　of　cooperation；　expressed　in　pooling　ideas　and　fame；　which　the　Wright　brothers　exemplified；　is　seen　again　in　the　association　of　Curtiss　with　the　navy　during　the　war。　NC　is　a　fraternity　badge　signifying　equal　honors。

Curtiss；　in　1900；　waslike　the　Wrightsthe　owner　of　a　small　bicycle　shop。　It　was　at　Hammondsport；　New　York。　He　was　an　enthusiastic　cyclist；　and　speed　was　a　mania　with　him。　He　evolved　a　motor　cycle　with　which　he　broke　all　records　for　speed　over　the　ground。　He　started　a　factory　and　achieved　a　reputation　for　excellent　motors。　He　designed　and　made　the　engine　for　the　dirigible　of　Captain　Thomas　S。　Baldwin；　and　for　the　first　United　States　army　dirigible　in　1905。

Curtiss　carried　on　some