the dominion of the air-第39部分

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ferent　in　velocity；　to　maintain　itself　in　air　without　effort　on　its　own　part。

Lord　Rayleigh；　proceeding　to　give　his　views　on　artificial　flight；　declares　the　main　problem　of　the　flying　machine　to　be　the　problem　of　the　aerial　plane。　　He　states　the　case　thus：　〃Supposing　a　plane　surface　to　be　falling　vertically　at　the　rate　of　four　miles　an　hour；　and　also　moving　horizontally　at　the　rate　of　twenty　miles　an　hour；　it　might　have　been　supposed　that　the　horizontal　motion　would　make　no　difference　to　the　pressure　on　its　under　surface　which　the　falling　plane　must　experience。　　We　are　told；　however；　that　in　actual　trial　the　horizontal　motion　much　increases　the　pressure　under　the　falling　plane；　and　it　is　this　fact　on　which　the　possibility　of　natural　and　artificial　flight　depends。

Ere　this　opinion　had　been　stated　by　Lord　Rayleigh　in　his　discourse　on　〃Flight；〃　at　the　Royal　Institution；　there　were　already　at　work　upon　the　aero…plane　a　small　army　of　inventors；　of　whom　it　will　be　only　possible　in　a　future　chapter　to　mention　some。　Due　reference；　however；　should　here　be　made　to　Mr。　W。　F。　Wenham；　of　Boston；　U。S。A。；　who　had　been　at　work　on　artificial　flight　for　many　years；　and　to　whose　labours　in　determining　whether　man's　power　is　sufficient　to　raise　his　own　weight　Lord　Rayleigh　paid　a　high　tribute。　　As　far　back　as　1866　Mr。　Wenham　had　published　a　paper　on　aerial　locomotion；　in　which　he　shows　that　any　imitation　by　man　of　the　far…extended　wings　of　a　bird　might　be　impracticable；　the　alternative　being　to　arrange　the　necessary　length　of　wing　as　a　series　of　aero…planes；　a　conception　far　in　advance　of　many　theorists　of　his　time。

But　there　had　been　developments　in　aerostation　in　other　lines；　and　it　is　time　to　turn　from　the　somewhat　tedious　technicalities　of　mechanical　flight　and　the　theory　or　practice　of　soaring；　to　another　important　means　for　traversing　the　airthe　parachute。　This　aerial　machine；　long　laid　aside；　was　to　lend　its　aid　to　the　navigation　of　the　air　with　a　reliability　never　before　realised。　　Professor　Baldwin；　as　he　was　termed；　an　American　aeronaut；　arrived　in　England　in　the　summer　of　1888；　and　commenced　giving　a　series　of　exhibitions　from　the　Alexandra　Palace　with　a　parachute　of　his　own　invention；　which；　in　actual　performance；　seems　to　have　been　the　most　perfect　instrument　of　the　kind　up　to　that　time　devised。　　It　was　said　to　be　about　18　feet　in　diameter；　whereas　that　of　Garnerin；　already　mentioned；　had　a　diameter　of　some　30　feet；　and　was　distinctly　top…heavy；　owing　to　its　being　thus　inadequately　ballasted；　for　it　was　calculated　that　its　enormous　size　would　have　served　for　the　safe　descent；　not　of　one　man；　but　of　four　or　five。　　Baldwin's　parachute；　on　the　contrary；　was　reckoned　to　give　safe　descent　to　250　lbs。；　which　would　include　weight　of　man　and　apparatus；　and　reduce　the　ultimate　fall　to　one　not　exceeding　8　feet。　The　parachute　was　attached　to　the　ring　of　a　small　balloon　of　12；000　cubic　feet；　and　the　Professor　ascended；　sitting　on　a　mere　sling　of　rope；　which　did　duty　for　a　car。

Mr。　Thomas　Moy；　who　investigated　the　mechanics　of　the　contrivance；　estimated　that　after　a　drop　of　16　feet；　the　upward　pressure；　amounting　to　over　2　lb。　per　square　foot；　would　act　on　a　surface　of　not　less　than　254　square　feet。　　There　was；　at　the　time；　much　foolish　comment　on　the　great　distance　which　the　parachute　fell　before　it　opened；　a　complete　delusion　due　to　the　fact　that　observers　failed　to　see　that　at　the　moment　of　separation　the　balloon　itself　sprang　upward。



CHAPTER　XXII。　　THE　STORY　OF　THE　SPENCERS。


It　has　been　in　the　hands　of　the　Spencers　that　the　parachute；　as　also　many　other　practical　details　of　aeronautics；　has　been　perfected；　and　some　due　sketch　of　the　career　of　this　family　of　eminent　aeronauts　must　be　no　longer　delayed。

Charles　Green　had　stood　godfather　to　the　youngest　son　of　his　friend　and　colleague；　Mr。　Edward　Spencer；　and　in　later　years；　as　though　to　vindicate　the　fact；　this　same　son　took　up　the　science　of　aeronautics　at　the　point　where　his　father　had　left　it。　　We　find　his　name　in　the　records　of　the　Patent　Office　of　1868　as　the　inventor　of　a　manumetric　flying　machine；　and　there　are　accounts　of　the　flying　leaps　of　several　hundred　feet　which　he　was　enabled　to　take　by　means　of　the　machine　he　constructed。　　Again；　in　1882　we　find　him　an　inventor；　this　time　of　the　patent　asbestos　fire　balloon；　by　means　of　which　the　principal　danger　to　such　balloons　was　overcome。

At　this　point　it　is　needful　to　make　mention　of　the　third　generationthe　several　sons　who　early　showed　their　zeal　and　aptitude　for　perpetuating　the　family　tradition。　　It　was　from　his　school　playground　that　the　eldest　son；　Percival；　witnessed　with　intense　interest　what　appeared　like　a　drop　floating　in　the　sky　at　an　immense　altitude。　　This　proved　to　be　Simmons's　balloon；　which　had　just　risen　to　a　vast　elevation　over　Cremorne　Gardens；　after　having　liberated　the　unfortunate　De　Groof；　as　mentioned　in　a　former　chapter。　　And　one　may　be　sure　that　the　terrible　reality　of　the　disaster　that　had　happened　was　not　lost　on　the　young　schoolboy。　　But　his　wish　was　to　become　an　aeronauts；　and　from　this　desire　nothing　deterred　him；　so　that　school　days　were　scarcely　over　before　he　began　to　accompany　his　father　aloft；　and　in　a　very　few　years；　i。e。　in　1888；　he　had　assumed　the　full　responsibilities　of　a　professional　balloonist。

It　was　in　this　year　that　Professor　Baldwin　appeared　in　England；　and　it　is　easy　to　understand　that　the　parachute　became　an　object　of　interest　to　the　young　Spencer；　who　commenced　on　his　own　account　a　series　of　trials　at　the　Alexandra　Palace；　and　it　was　now；　also；　that　chance　good　fortune　came　his　way。　　An　Indian　gentleman；　who　was　witness　of　his　experiments；　and　convinced　that　a　favourable　field　for　their　further　development　existed　in　his　own　country；　proposed　to　the　young　aspirant　that　he　should　accompany　him　to　India；　with　equipment　suited　for　the　making　of　a　successful　campaign。

Thus　it　came　about　that　in　the　early　days　of　1889；　in　the　height　of　the　season；　Mr。　Percival　Spencer　arrived　at　Bombay；　and　at　once　commenced　professional　business　in　earnest。　　Coal　gas　being　here　available；　a　maiden　ascent　was　quickly　arranged；　and　duly　announced　to　take　place　at　the　Government　House；　Paral；　the　chief　attraction　being　the　parachute　descent；　the　first　ever　attempted　in　India。

This　preliminary　exhibition　proving　in　all　ways　a　complete　success；　Mr。　Spencer；　after　a　few　repetitions　of　his　performance；　repaired　to　Calcutta；　but　here　great　difficulties　were　experienced　in　the　matter　of　gas。　　The　coal　gas　available　was　inadequate；　and　when　recourse　was　had　to　pure　hydrogen　the　supply　proved　too　sluggish。　　At　the　advertised　hour　of　departure　the　balloon　was　not　sufficiently　inflated；　while　the　spectators　were　growing　impatient。　　It　was　at　this　critical　moment　that　Mr。　Spencer　resolved　on　a　surprise。　　Suddenly　casting　off　the　parachute；　and　seated　on　a　mere　sling　below　the　half…inflated　balloon；　without　ballast；　without　grapnel；　and　unprovided　with　a　valve；　he　sailed　away　over　the　heads　of　the　multitude。

The　afternoon　was　already　far　advanced；　and　the　short　tropical　twilight　soon　gave　way　to　darkness；　when　the　intrepid　voyager　disappeared　completely　from　sight。　　Excitement　was　intense　that　night　in　Calcutta；　and　greater　still　the　next　day　when；　as　hour　after　hour　went　by；　no　news　save　a　series　of　wild　and　false　reports　reached　the　city。　　Trains　arriving　from　the　country　brought　no　intelligence；　and　telegraphic　enquiries　sent　in　all　directions　proved　fruitless。　　The　Great　Eastern　Hotel；　where　the　young　man　had　been　staying；　was　literally　besieged　for　hours　by　a　large　crowd　eager　for　any　tidings。　　Then　the　Press　gave　expression　to　the　gloomiest　forebodings；　and　the　town　was　in　a　fever　of　unrest。　　From　the　direction　the　balloon　had　taken　it　was　thought　that；　even　if　the　aeronaut　had　descended　in　safety；　he　could　only　have　been　landed　in　the　jungle　of　the　Sunderbunds；　beset　with　perils；　and　without　a　chance　of　succour。　　A　large　reward　was　offered　for　reliable　information；　and　orders　were　issued　to　every　likely　station　to　organise　a　search。　　But　ere　this　was　fully　carried　into　effect　messages　were　telegraphed　to　England　definitely　asserting　that　Mr。　Spencer　had　lost　his　life。　　For　all　this；　after　three　days　he　returned　to　Calcutta；　none　the　worse　for　the　exploit。

Then　the　true　tale　was　unravelled。　　The　balloon　had　changed　its　course　from　S。E。　to　E。　after　passing　out　of　sight　of　Calcutta；　and　eventually　came　to　earth　the　same　evening　in　the　neighbourhood　of　Hossainabad；　thirty…six　miles　distant。　　During　his　aerial　flight　the　voyager's　main　trouble　had　been　caused　by　his　cramped　position；　the　galling　of　his　sling　seat；　and　the　numbing　effect　of　cold　as　he　reached　high　altitudes；　but；　as　twilight　darkened　into　gloom；　his　real　anxiety　was　with　respect　to　his　place　of　landing；　for　he　could　with　difficulty　see　the　earth　underneath。　　He　heard　the　distant　roll　of　the　waters；　caused　by　the　numerous　creeks　which　intersect　the　delta　of　the　Ganges；　and　when　darkness　completely　shut　out　the　view　it　was　impossible　to　tell　whether　he　was　over　land　or　sea。　　Fortune　favoured　him；　however；　and　reaching　dry　ground；　he　sprang　from　his　seat；　relinquishing　at　the　same　moment　his　hold　of　the　balloon；　which　instantly　disappeared　into　the　darkness。

Then　his　wanderings　began。　　He　was　in　an　unknown　country；　without　knowledge　of　the　language；　and　with　only　a　few　rupees　in　his　pocket。　　Presently；　however；　seeing　a　light；　he　proceeded　towards　it；　but　only　to　find　himself　stopped　by　a　creek。　　Foiled　more　than　once　in　this　way；　he　at　length　arrived　at　the　dwelling　of　a　family　of　natives；　who　promptly　fled　in　terror。　　To　inspire　confidence　and　prove　that　he　was　mortal；　Mr。　Spencer　threw　his　coat　over　the　mud　wall　of　the　compound；　with　the　result　that；　after　examination　of　the　garment；　he　was　received　and　cared　for　in　true　native　fashion；　fed　with　rice　and　goat's　milk；　and　allowed　the　use　of　the　verandah　to　sleep　in。　　He　succeeded　in　communing　with　the　natives　by　dint　of　lead　pencil　sketches　and　dumb　show；　and　learned；　among　other　things；　that　he　had　descended　in　a　little　clearing　surrounded　by　woods；　and　bounded　by　tidal　creeks；　which　were　infested　with　alligators。　　Yet；　in　the　end；　the　waterways　befriended　him；　for；　as　he　was　b