the dominion of the air-第16章

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It　is　when　we　come　to　consider　the　impressions　and　sensations　described　by　sky　voyagers　of　bygone　times　that　we　find　them　curiously　at　variance　with　our　own。　　As　an　instance；　we　may　state　that　the　earth；　as　seen　from　a　highflying　balloon；　used　to　be　almost　always　described　as　appearing　concave；　or　like　a　huge　basin；　and　ingenious　attempts　were　made　to　prove　mathematically　that　this　must　be　so。　　The　laws　of　refraction　are　brought　in　to　prove　the　fact；　or；　again；　the　case　is　stated　thus：　　Supposing　the　extreme　horizon　to　be　seen　when　the　balloon　is　little　more　than　a　mile　high；　the　range　of　view　on　all　sides　will　then　be；　roughly；　some　eighty　miles。　　If；　then；　a　line　were　drawn　from　the　aerial　observer　to　this　remote　distance；　that　line　would　be　almost　horizontal；　so　nearly　so　that　he　cannot　persuade　himself　that　his　horizon　is　otherwise　than　still　on　a　level　with　his　eye；　yet　the　earth　below　him　lies；　as　it　seems；　at　the　bottom　of　a　huge　gulf。　　Thus　the　whole　visible　earth　appears　as　a　vast　bowl　or　basin。　　This　is　extremely　ingenious　reasoning；　and　not　to　be　disregarded；　but　the　fact　remains　that　in　the　experience　of　the　writer　and　of　many　others　whom　he　has　consulted；　there　is　no　such　optical　illusion　as　I　have　just　discussed；　and　to　their　vision　it　is　impossible　to　regard　the　earth　as　anything　but　uniformly　flat。

Another　impression　invariably　insisted　on　by　early　balloonists　is　that　the　earth；　on　quitting　it；　appears　to　drop　away　into　an　abyss；　leaving　the　voyagers　motionless；　and　this　illusion　must；　indeed；　be　probably　universal。　　It　is　the　same　illusion　as　the　apparent　gliding　backwards　of　objects　to　a　traveller　in　a　railway　carriage；　only　in　this　latter　case　the　rattling　and　shaking　of　the　carriage　helps　the　mind　to　grasp　the　real　fact　that　the　motion　belongs　to　the　train　itself；　whereas　it　is　otherwise　with　a　balloon；　whose　motion　is　so　perfectly　smooth　as　to　be　quite　imperceptible。

Old　ideas；　formed　upon　insufficient　observations；　even　if　erroneous；　were　slow　to　die。　　Thus　it　used　to　be　stated　that　an　upper　cloud　floor　adapted　itself　to　the　contour　of　the　land　over　which　it　rested；　giving　what　Mr。　Monck　Mason　has　called　a　〃phrenological　estimate〃　of　the　character　of　the　earth　below；　the　clouds；　〃even　when　under　the　influence　of　rapid　motion；　seeming　to　accommodate　themselves　to　all　variations　of　form　in　the　surface　of　the　subjacent　soil；　rising　with　its　prominences　and　sinking　with　its　depressions。〃　　Probably　few　aeronauts　of　the　present　time　will　accept　the　statement。

It　used　commonly　to　be　asserted；　and　is　so　often　to　this　day；　that　a　feeling　as　of　sea…sickness　is　experienced　in　balloon　travel；　and　the　notion　has　undoubtedly　arisen　from　the　circumstances　attending　an　ascent　in　a　captive　balloon。　　It　were　well；　now　that　ballooning　bids　fair　to　become　popular；　to　disabuse　the　public　mind　of　such　a　wholly　false　idea。　　The　truth　is　that　a　balloon　let　up　with　a　lengthy　rope　and　held　captive　will；　with　a　fitful　breeze；　pitch　and　sway　in　a　manner　which　may　induce　all　the　unpleasant　feelings　attending　a　rough　passage　at　sea。　　It　may　do　worse；　and　even　be　borne　to　earth　with　a　puff　of　wind　which　may　come　unexpectedly；　and　considerably　unsettle　the　nerves　of　any　holiday　passenger。　　I　could　tell　of　a　〃captive〃　that　had　been　behaving　itself　creditably　on　a　not　very　settled　day　suddenly　swooping　over　a　roadway　and　down　into　public　gardens；　where　it　lay　incontinently　along　the　ground；　and　then；　before　the　astonished　passengers　could　attempt　to　alight；　it　was　seized　with　another　mood；　and；　mounting　once　again　majestically　skyward；　submitted　to　be　hauled　down　with　all　becoming　grace　and　ease。　　It　is　owing　to　their　vagaries　and　want　of　manageability　that；　as　will　be　shown；　〃captives〃　are　of　uncertain　use　in　war。　　On　the　other　hand；　a　free　balloon　is　exempt　from　such　disadvantages；　and　at　moderate　heights　not　the　smallest　feeling　of　nausea　is　ever　experienced。　　The　only　unpleasant　sensation；　and　that　not　of　any　gravity；　ever　complained　of；　is　a　peculiar　tension　in　the　ears　experienced　in　a　rapid　ascent；　or　more　often；　perhaps；　in　a　descent。　　The　cause；　which　is　trivial　and　easily　removed；　should　be　properly　understood；　and　cannot　be　given　in　clearer　language　than　that　used　by　Professor　Tyndall：〃Behind　the　tympanic　membrane　exists　a　cavitythe　drum　of　the　earin　part　crossed　by　a　series　of　bones；　and　in　part　occupied　by　air。　　This　cavity　communicates　with　the　mouth　by　means　of　a　duct　called　the　Eustachian　tube。　　This　tube　is　generally　closed；　the　air　space　behind　the　tympanic　membrane　being　thus　cut　off　from　the　external　air。　　If；　under　these　circumstances；　the　external　air　becomes　denser；　it　will　press　the　tympanic　membrane　inwards；　if；　on　the　other　hand；　the　air　on　the　other　side　becomes　rarer；　while　the　Eustachian　tube　becomes　closed；　the　membrane　will　be　pressed　outwards。　　Pain　is　felt　in　both　cases；　and　partial　deafness　is　experienced。。。。　By　the　act　of　swallowing　the　Eustachian　tube　is　opened；　and　thus　equilibrium　is　established　between　the　external　and　internal　pressure。〃

Founded　on　physical　facts　more　or　less　correct　in　themselves；　come　a　number　of　tales　of　olden　days；　which　are　at　least　more　marvellous　than　credible；　the　following　serving　as　an　example。　　The　scientific　truth　underlying　the　story　is　the　well…known　expedient　of　placing　a　shrivelled　apple　under　the　receiver　of　an　air　pump。　　As　the　air　becomes　rarefied　the　apple　swells；　smooths　itself　out；　and　presently　becomes　round　and　rosy　as　it　was　in　the　summer　time。　　It　is　recorded　that　on　one　occasion　a　man　of　mature　years　made　an　ascent；　accompanied　by　his　son；　and；　after　reaching　some　height；　the　youth　remarked　on　how　young　his　father　was　looking。　　They　still　continued　to　ascend；　and　the　same　remark　was　repeated　more　than　once。　　And　at　last；　having　now　reached　attenuated　regions；　the　son　cried　in　astonishment；　〃Why；　dad；　you　ought　to　be　at　school！〃　　The　cause　of　this　remark　was　that　in　the　rarefied　air　all　the　wrinkles　had　come　out　of　the　old　man's　face；　and　his　cheeks　were　as　chubby　as　his　son's。

This　discussion　of　old　ideas　should　not　be　closed　without　mention　of　a　plausible　plea　for　the　balloon　made　by　Wise　and　others　on　the　score　of　its　value　to　health。　　Lofty　ascents　have　proved　a　strain　on　even　robust　constitutionsthe　heart　may　begin　to　suffer；　or　ills　akin　to　mountain　sickness　may　intervene　before　a　height　equal　to　that　of　our　loftiest　mountain　is　reached。　　But　many　have　spoken　of　an　exhilaration　of　spirits　not　inferior　to　that　of　the　mountaineer；　which　is　experienced；　and　without　fatigue；　in　sky　voyages　reasonably　indulged　inof　a　light…heartedness；　a　glow　of　health；　a　sharpened　appetite；　and　the　keen　enjoyment　of　mere　existence。　　Nay；　it　has　been　seriously　affirmed　that　〃more　good　may　be　got　by　the　invalid　in　an　hour　or　two　while　two　miles　up　on　a　fine　summer's　day　than　is　to　be　gained　in　an　entire　voyage　from　New　York　to　Madeira　by　sea。〃



CHAPTER　X。　THE　COMMENCEMENT　OF　A　NEW　ERA。


Resuming　the　roll　of　progressive　aeronauts　in　England　whose　labours　were　devoted　to　the　practical　conquest　of　the　air；　and　whose　methods　and　mechanical　achievements　mark　the　road　of　advance　by　which　the　successes　of　to…day　have　been　obtained；　there　stand　out　prominently　two　individuals；　of　whom　one　has　already　received　mention　in　these　pages。

The　period　of　a　single　life　is　seldom　sufficient　to　allow　within　its　span　the　full　development　of　any　new　departure　in　art　or　science；　and　it　cannot；　therefore；　be　wondered　at　if　Charles　Green；　though　reviving　and　re…modelling　the　art　of　ballooning　in　our　own　country；　even　after　an　exceptionally　long　and　successful　career；　left　that　pursuit　to　which　he　had　given　new　birth　virtually　still　in　its　infancy。

The　year　following　that　in　which　Green　conducted　the　famous　Nassau　voyage　we　find　him　experimenting　in　the　same　balloon　with　his　chosen　friend　and　colleague；　Edward　Spencer；　solicitor；　of　Barnsbury；　who；　only　nine　years　later；　compiles　memoranda　of　thirty…four　　ascents；　made　under　every　variety　of　circumstance；　　many　being　of　a　highly　enterprising　nature。　　We　find　him　writing　enthusiastically　of　the　raptures　he　experienced　when　sailing　over　London　in　night　hours；　of　lofty　ascents　and　extremely　low　temperatures；　of　speeding　twenty…eight　miles　in　twenty　minutes；　of　grapnel　ropes　breaking；　and　of　a　cross…country　race　of　four　miles　through　woods　and　hedges。　　Such　was　Mr。　Spencer　the　elder；　and　if　further　evidence　were　needed　of　his　practical　acquaintance　with；　as　well　as　personal　devotion　to；　his　adopted　profession　of　aeronautics；　we　have　it　in　the　store　of　working　calculations　and　other　minutiae　of　the　craft；　most　carefully　compiled　in　manuscript　by　his　own　hand；　these　memoranda　being　to　this　day　constantly　consulted　by　his　grandsons；　the　present　eminent　aeronauts；　Messrs。　Spencer　Brothers；　as　supplying　a　manual　of　reliable　data　for　the　execution　of　much　of　the　most　important　parts　of　their　work。

In　the　terrific　ordeal　and　risk　entailed　by　the　daring　and　fatal　parachute　descent　of　Cocking；　Green　required　an　assistant　of　exceptional　nerve　and　reliability；　and；　as　has　been　recorded；　his　choice　at　once　fell　on　Edward　Spencer。　　In　this　choice　it　has　already　been　shown　that　he　was　well　justified；　and　in　the　trying　circumstances　that　ensued　Green　frankly　owns　that　it　was　his　competent　companion　who　was　the　first　to　recover　himself。　　A　few　years　later；　when　a　distinguished　company；　among　whom　were　Albert　Smith　and　Shirley　Brooks；　made　a　memorable　ascent　from　Cremorne；　Edward　Spencer　is　one　of　the　select　party。

Some　account　of　this　voyage　should　be　given；　and　it　need　not　be　said　that　no　more　graphic　account　is　to　be　found　than　that　given　by　the　facile　pen　of　Albert　Smith　himself。　　His　personal　narrative　also　forms　an　instructive　contrast　to　another　which　he　had　occasion　to　give　to　the　world　shortly　afterwards；　and　which　shall　be　duly　noticed。　　The　enthusiastic　writer　first　describes；　with　apparent　pride；　the　company　that　ascended　with　him。　　Besides　Mr。　Shirley　Brooks；　there　were　Messrs。　Davidson；　of　the　Garrick　Club；　Mr。　John　Lee；　well　known　in　theatrical　circles；　Mr。　P。　　Thompson；　of　Guy's　Hospital；　and　othersten　in　all；　including　Charles　Green　as　skipper；　and　Edward　Spencer；　who；　sitting　in　the　rigging；　was　entrusted　with　the　all…important　management　of　the　valve　rope。

〃The　first　sensation　experienced；〃　Albert　Smith　continues；　〃was　not　that　we　were　rising；　but　that　the　balloon　remained　fixed；　whilst　all　the　world　below　was　rapidly　falling　away；　while　the　cheers　with　which　they　greeted　our　departure　grew　fainter；　and　the　cheerers　themselves　began　to　look　like　the　inmates　of　many　sixpenny　Noah's　Arks　grouped　upon　a　billiard　table。。。。　Our　hats　would　have　held　millions。。。。　And　most　strange　is　the　roar　of　the　city　as　it　comes　surging　into　the　welkin　as　though　the　whole　metropolis　cheered　you　with　one　voice。。。。　Yet　none　beyond　the　ordinary　passengers　are　to　be　seen。　　The　noise　is　as　inexplicable　as　the　murmur　in　the　air　at　hot　summer　noontide。〃

The　significance　of　this　last　remark　will　be　insisted　on　when　the　writer　has　to　tell　his　own　experiences　aloft　over　London；　as　also　a　note　to　the　effect　that　there　were　seen　〃large　enclosed　fields　and　gardens　and　pleasure　grounds　where　none　were　supposed　to　exist　by　ordinary　passengers。〃　　Another　interes