投诉 阅读记录

第18章

Amodificationofthisinstrument,asemployedbythewriter,consistedofalight,spherical,drum—shapedframeoflargesize,which,whencoveredwithdarkmaterialandhungintheclearbelowthecarofaloftyballoon,couldbewellseeneitheragainstblueskyorgreyatagreatdistance。Theso—calleddrumcould,byaverysimplecontrivance,readilyworkedfromthecar,bemadetocollapseintoaveryinconspicuousobject,andthusbecapableofdisplayingMorseCodesignals。Alongpausewiththedrumextended——likethelongwaveofasignallingflag——woulddenotea"dash,"andashortpausea"dot,"andthesemotionswouldbeatonceintelligibletoanyoneacquaintedwiththenowuniversalMorseCodesystem。

Providedwithanapparatusofthekind,thewritermadeanascentfromNewburyatatimewhenthemilitarycampswerelyingonSalisburyPlainatadistanceofnearlytwentymilestothesouth—west。Thegroundwindupto2,500feetonstartingwasnearlyduenorth,andwouldhavedefeatedtheattempt;again,theairstreamblowingabovethatheightwasnearlydueeast,whichagainwouldhaveprovedunsuitable。Butitwasmanifestlypossibletoutilisethetwocurrents,andwithgoodlucktozig—zagone’scoursesoastocomewithineasysignallingdistanceofthevariouscamps;and,asamatteroffact,weactuallypassedimmediatelyoverBulfordCamp,withwhichweexchangedsignals,whiletwoothercampslayclosetorightandleftofus。Fortunefavouringus,wehadactuallyhitourmark,thoughitwouldhavebeensufficientfortheexperimenthadourcourselainwithintenmilesrightorleft。

Yetafurtherusefortheballooninwarfareremainsuntriedinthiscountry。ActingundertheadviceofexpertsintheService,thewriter,intheearlypartofthepresentyear,suggestedtotheAdmiraltythedesirabilityofexperimentingwithballoonsasameansofdetectingsubmarineenginesofwar。

Itiswellknownthatreefsandshoalscangenerallybeseenfromaclifformastheadfarmoreclearlythanfromthedeckorotherpositionnearthesurfaceofthewater。Wouldnot,then,aballoon,ifskilfullymanoeuvred,serveasavaluablepostofobservation?TheAdmiralty,inacknowledgingthecommunication,promisedtogivethemattertheirattention;butbythemonthofJunethePresshadannouncementsofhowtheself—sameexperimentshadbeensuccessfullycarriedthroughbyFrenchauthorities,whileafewdayslatertheAdmiraltywrote,"Forthepresentnoneedisseenfortheuseofacaptiveballoontodetectsubmarines。"

Amongmanyandvariedballooningincidentswhichhaveoccurredtothewriter,therearesomewhichmaynotunprofitablybecomparedwithcertainexperiencesalreadyrecordedofotheraeronauts。Thunderstorms,aswitnessedfromaballoon,havealreadybeencasuallydescribed,anditmayreasonablybehopedthattheobservationswhichhave,undervaryingcircumstances,beenmadeathighaltitudesmaythrowsomeadditionallightonthisfamiliar,thoughsomewhatperplexing,phenomenon。

Tobeginwith,itseemsamootpointwhetheraballooncaughtinathunderstormis,orisnot,inanyspecialdangerofbeingstruck。Ithasbeenarguedthatimmunityundersuchcircumstancesmustdependuponwhetherasufficientlylongtimehaselapsedsincetheballoonlefttheearthtoallowofitsbecomingpositivelyelectrifiedbyinductionfromthecloudsorbyrainfallinguponitssurface。Buttherearemanyotherpointstobeconsidered。Thereistheconstantescapeofgasfromthemouth;thereisthemassofpointedmetalintheanchor;and,again,itisconceivablethataballoonrapidlydescendingoutofathunderstormmightcarrywithitachargeresidingonitsmoistenedsurfacewhichmightmanifestitselfdisastrouslyastheballoonreachedtheearth。

Instancesseemtohavebeennotinfrequentofballoonsencounteringthunderstorms;but,unfortunately,inmostcasestheobservershavenothadanyscientifictraining,ortheaccountswhicharetohandarethoseofthetypeofjournalistwhoischieflyinquestofsensationalcopy。

ThusthereisanaccountfromAmericaofaProfessorKingwhomadeanascentfromBurlington,Iowa,justasathunderstormwasapproaching,withtheresultthat,insteadofscuddingawaywiththewindbeforethestorm,hewasactually,asifbysomeattraction,drawnintoit。Onthishisaimwastopiercethroughthecloudabove,andthenfollowsadescriptionwhichitishardtorealise:——"Therecamedowninfrontofhim,andapparentlynotmorethan50feetdistant,agranddischargeofelectricity。"Thenhefeelsthecarlifted,thegassuddenlyexpandstooverflowing,andtheballoonishurledthroughthecloudwithinconceivablevelocity,thishappeningseveraltimes,withtremendousoscillationsofthecar,untiltheballoonisbornetoearthinatorrentofrain。Wefancythatmanypracticalballoonistswillhardlyendorsethisdescription。

Butwehaveanother,relatingtooneofthemostdistinguishedaeronauts,M。EugeneGodard,who,inanascentwithlocaljournalists,wascaughtinathunderstorm。Herewearetold——presumablybythejournalists——that"twicethelightningflashedwithinafewyardsoftheterror—strickencrew。"

Onceagain,inanascentatDerby,aspectatorwrites:——"Thelightningplayeduponthesphereoftheballoon,lightingitupandmakingthingsvisiblethroughit。"This,however,onemustsuppose,canhardlyapplytotheballoonwhenliberated。

Butagraphicdescriptionofaverydifferentcharactergiveninthe"QuarterlyJournaloftheRoyalMeteorologicalSociety"

forJanuary,1901,isofrealvalue。ItappearsthatthreelieutenantsofthePrussianBalloonCorpstookchargeofaballoonthatascendedatBerlin,and,whenataheightof2,300

feet,becameenvelopedinthemist,throughwhichonlyoccasionalglimpsesofearthwereseen。Atthispointasharp,cracklingsoundwasheardatthering,likethesparkingofahugeelectricalmachine,and,lookingup,thevoyagersbeheldsparksapparentlysomehalf—inchthick,andovertwofeetinlength,playingfromthering。Thunderwasheard,but——andthismayhavesignificance——onlybeforeandaftertheabovephenomenon。

AnotherinstructiveexperienceisrecordedoftheyoungerGreeninanascentwhichhemadefromFrankfort—on—the—Maine。Onthisoccasionherelatesthatheencounteredathunderstorm,andataheightof4,400feetfoundhimselfatthelevelwherethestormcloudsweredischargingthemselvesinadeluge。Heseemstohavehadnodifficultyinascendingthroughthestormintotheclearskyabove,whereabreezefromanotherquarterquicklycarriedhimawayfromthestormcentre。

Thisco—existence,orconflictofoppositecurrents,isheldtobethecommoncharacteristic,ifnotthemaincause,ofthunderstorms,andtallieswiththefollowingpersonalexperience。ItwasintypicalJulyweatherof1900thatthewriterandhisson,accompaniedbyAdmiralSirEdmundFremantleandMr。PercivalSpencer,madeaneveningascentfromNewbury。

Ithadbeenadayofstorms,butabout5p。m。,afterwhatappearedtobeaclearingshower,theskybrightened,andwesailedupintoacloudlessheaven。Thewind,at3,000feet,wastravellingatsomethirtymilesanhour,anderethedistanceoftenmileshadbeencoveredaformidablethunderpackwasseenapproachingandcomingupdeadagainstthewind。

Nothingcouldbemoreevidentthanthattheballoonwastravellingrapidlywithalowerwind,whilethestormwasbeingborneequallyrapidlyonanupperanddiametricallyoppositecurrent。Itprovedoneofthemostseverethunderstormsrememberedinthecountry。ItbroodedforfivehoursoverDevizes,afewmilesahead。Ahomesteadonourrightwasstruckandburnedtotheground,whileonourlefttwosoldierswerekilledonSalisburyPlain。Theskyimmediatelyoverheadwas,ofcourse,hiddenbythelargeglobeoftheballoon,butaroundandbeneathusthestormseemedtogatherinabluegreymist,whichquicklybroadenedanddeepenedtill,almostbeforewecouldrealiseit,wefoundourselvesintheveryheartofthestorm,thelightningplayingallaroundus,andthesharphailstingingourfaces。

Thecountrymenbelowdescribedtheballoonasapparentlyenvelopedbythelightning,butwithourselves,thoughtheflasheswereincessant,andonallsides,thereverberationsofthethunderwerenotremarkable,beingratherbriefexplosionsinwhichtheyresembledthethunderclapsnotinfrequentlydescribedbytravellersonmountainheights。

Theballoonwasnowdescendingfromadoublecause:theweightofmoisturesuddenlyaccurnulatedonitssurface,andtheveryobviousdownrushofcoldairthataccompaniedthestormofpeltinghail。Withaverylimitedstoreofballast,itseemedimpossibletomakeafurtherascent,norwasthisdesirable。

Thesignallingexperimentsonwhichwewereintentcouldnotbecarriedoninsuchweather。Theonlycoursewastodescend,andthoughthiswasnotatoncepracticable,owingtoSavernakeForestbeingbeneathus,weeffectedasafelandinginthefirstavailableclearing。

Ashasbeenmentioned,Mr。Glaisherandotherobservershaverecordedseveralremarkableinstancesofoppositewindcurrentsbeingmetwithatmoderatealtitudes。None,however,canhavebeenmorenoteworthyorsurprisingthanthefollowingexperienceOfthewriteronWhitMondayof1899。Theascentwasunderanovercastsky,fromtheCrystalPalaceat3p。m。,atwhichhouracolddrizzlewassettlinginwithamoderatebreezefromtheeast。Thus,startingfromtheusualfillinggroundnearthenorthtower,theballoonsailedoverthebodyofthePalace,andthenceoverthesuburbstowardsthewesttilllostinthemist。Wethenascendedthrough1,500feetofdense,wettingcloud,and,emerginginbrightsunshine,continuedtodriftfortwohoursatanaveragealtitudeofsome3,000feet;1,000feetbelowuswastheill—defined,everchanginguppersurfaceofthedensecloudfloor,anditwasnolongerpossibletodetermineourcourse,whichwethereforeassumedtohaveremainedunchanged。Atlength,however,asameasureofprudence,wedeterminedtodescendthroughthecloudssufficientlytolearnsomethingofourwhereabouts,whichwereasonablyexpectedtobesomewhereinSurreyorBerks。Onemerging,however,belowthecloud,thefirstobjectthatloomedoutofthemistirnmediatelybelowuswasacargovessel,intheriggingofwhichourtrailropewasentanglingitself。OnlybydegreesthefactdawneduponusthatwewereintheestuaryoftheThames,andbeatinguptowardsLondononceagainwithancastwind。Thusitbecameevidentthatatthehigherlevel,unknowntoourselves,wehadbeenheadedbackonourcourse,fortwohours,byawinddiametricallyopposedtothatblowingontheground。

Tworecentdevelopmentsofthehot—airwarballoonsuggestgreatpossibilitiesinthenearfuture。Onetakestheformofasmallcaptive,carryingaloftaphotographiccameradirectedandoperatedelectricallyfromtheground。Theotherisaself—containedpassengerballoonoflargedimensions,carryingincompletesafetyaspecialpetroleumburnerofgreatpower。

ThesenewandimportantdeparturesaremainlyduetothemechanicalgeniusofMr。J。N。Maskelyne,whohaspatentedandperfectedtheminconjunctionwiththewriter。

CHAPTERXXVIII。THECONSTITUTIONOFTHEAIR。

Somefairideaoftheconditionsprevailingintheupperairmayhavebeengatheredfromthemanyandvariousobservationsalreadyrecorded。Statingthecasebroadly,wemayassertthatthesameatmosphericchangeswithwhichwearefamiliarattheleveloftheeartharetobefoundalsoatallaccessibleheights,equallyextensiveandequallysudden。

Standingonanopenheathonagustyday,wemayoftennotetherhythmicbuffetingofthewind,resemblingtheassaultofrollingbillowsofair。Theevidenceofthesebillowshasbeenactuallytracedfaraloftinballoontravel,whenaeronauts,lookingdownonawind—sweptsurfaceofcloud,haveobservedthissurfacetobethrownintoaseriesofrollsofvapour,whichwerebutvastandveritablewavesofair。Theintervalbetweensuccessivecrestsofthesewaveshasononeoccasionbeenestimatedatapproximatelyhalfamile。Wehaveseenhowtheseairstreamssometimesholdwideandindependentswayatdifferentlevels。Wehaveseen,too,howtheysometimesmeetandmingle,notinfrequentlyattendedwithelectricaldisturbanceThroughbroaddriftsofairminorairstreamswouldseemoftenliterallyto"thread"theirway,breakngupintofilamentsorwanderingrillsofair。InthevoyageacrossSalisburyPlainlatelydescribed,whiletheballoonwasbeingcarriedwiththemoresluggishcurrent,anumberofsmallparachutesweredroppedoutatfrequentintervalsandcarefullywatched。Thesewouldcommonlyattendtheballoonforalittlewhile,until,gettingintosomeminorairstream,theywouldsuddenlyandrapidlydivergeatsuchwideanglesastosuggestthatcrossingouractualcoursethereweresidepaths,downwhichthesmallerbodiesbecamewafted。

Onanotheroccasionthewritermetwithstronglymarkedandaltogetherexceptionalevidenceofthevehemenceandpersistenceoftheseminoraerialstreamlets。ItwasonanoccasioninAprilweather,whenaheavyovercastskyblottedouttheupperheavens。Inthecloudlevelsthewindwassomewhatsluggish,andforanhourwetravelledatanaveragespeedofalittleovertwentymilesanhour,neverhigherthan3,000feet。Atthispoint,whileflyingoverHertfordshire,wethrewoutsufficientballasttocausetheballoontoriseclearofthehazylowerair,andcomingunderthefullinfluenceofthesun,theninthemeridian,weshotupwardsatconsiderablespeed,andsoonattainedanaltitudeofthreemiles。Butforaconsiderableportionofthisclimb——while,infact,wewereascendingthroughlittlelessthanamileofourupwardcourse——wewereassailedbyimpetuouscrosscurrents,whichwhistledthroughcarandriggingandsmoteusfairlyonthecheek。Itwasaltogetheranovelexperience,andthemoreremarkablefromthefactthatourmainonwardcoursewasnotappreciablydiverted。

Thenwegotabovethesecurrents,andremainedatourmaximumlevel,whilewefloated,stillatonlyamoderatespeed,thelengthofacounty。Thedescentthenbegan,andonceagain,whilewedroppedthroughthesamedisturbedregion,thesamefar—reachingandobtrusivecross—currentassailedus。Itwasquiteobviousthatthevehementcurrentsweretooslendertotelllargelyuponthehugesurfaceoftheballoon,asitwasbeingsweptsteadilyonwardsbythemainwind,whichnevervariedindirectionfromgroundlevelsuptothegreatestheightattained。

ThisexperienceisbutconfirmationofthestoryofthewindtoldbythewindgaugesontheForthBridge。Herethemaximumpressuremeasuredonthelargegaugeof300squarefeetiscommonlyconsiderablylessthanthatonthesmallergauge,suggestingthatthelattermustbeduetothreadsofairoflimitedareaandhighvelocity。

Furtherandveryvaluablelightisthrownonthepeculiarwaysofthewind,nowbeingconsidered,byProfessorLangleyinthespecialresearchesofhistowhichreferencehasalreadybeenmade。Thiseminentobserverandmathematician,suspectingthattheold—fashionedinstruments,whichonlytoldwhatthewindhadbeendoingeveryhour,oratbesteveryminute,gavebutamostimperfectrecord,constructeddelicategauges,whichwouldrespondtoeveryimpulseandgivereadingsfromsecondtosecond。

Inthiswayheestablishedthefactthatthewind,farfrombeingabodyofevenapproximateuniformity,isundermostordinaryconditionsirregularalmostbeyondconception。

Further,thatthegreaterthespeedthegreaterthefluctuations,sothatahighwindhastoberegardedas"airmovinginatumultuousmass,"thevelocityatonemomentperhapsfortymilesanhour,thendiminishingtoanalmostinstantaneouscalm,andthenresuming。"Infact,intheverynatureofthecase,windisnottheresultofonesimplecause,butofaninfinitenumberofimpulsesandchanges,perhapslongpassed,whicharepreservedinit,andwhichdieonlyslowlyaway。"

Whenwecometotakeobservationsoftemperaturewefindtheconditionsintheatmosphereaboveustobeatfirstsightnotalittlecomplex,andaltogetherdifferentindayandnighthours。Fromobservationsalreadyrecordedinthisvolume——notablythoseofGayLussac,Welsh,andGlaisher——ithasbeenmadetoappearthat,inascendingintotheskyindaytime,thetemperatureusuallyfallsaccordingtoagenerallaw;buttherearefoundregionswherethefalloftemperaturebecomesarrested,suchregionsbeingcommonly,thoughbynomeansinvariably,associatedwithvisiblecloud。Itisprobable,however,thatitwouldbemorecorrectnottointerpretthepresenceofcloudascausingmanifestationofcold,butrathertoregardthemeetingofwarmandcoldcurrentsasthecauseofcloud。

Thewriterhasexperimentedintheupperregionswithaspecialformofairthermometerofgreatsensibility,designedtorespondrapidlytoslightvariationsoftemperature。Testingthisinstrumentononeoccasioninaroomofequablewarmth,andwithoutdraughts,hewaspuzzledbyseeingtheindexinacapillarytubesuddenlymountingrapidly,duetosomecausewhichwasnotapparent,tillitwasnoticedthattheparlourcat,attractedbytheproceedings,hadapproachedneartheapparatus。Thebehaviourofthisinstrumentwhenslungintheclearsomedistanceoverthesideoftheballooncar,andcarefullywatched,suggestsbyitsfitful,sudden,andrapidchangesthatwarmercurrentsareoftenmakingtheirwayinsuchslenderwanderingrillsashavebeenalreadypicturedaspermeatingthebroaderairstreams。Duringnighthoursconditionsarereversed。Thewarmerairradiatedofftheearththroughthedayhasthenascended。Itwillbefoundatdifferentheights,lyinginpoolsorstrata,possiblyresemblinginform,couldtheybeseen,massesofvisiblecloud。

Thewriterhasgatheredfromnightvoyagesinstructiveandsuggestivefactswithreferencetotheascentofairstreams,duetodifferencesoftemperature,particularlyoverLondonandthesuburbs,anditisconceivablethatinsuchascendingstreamsmaylieameansofdealingsuccessfullywithvisitationsofsmokeandfog。

Onelessontaughtbyballoontravelhasbeenthatfogorhazewillcomeorgoinobediencetotemperaturevariationsatlowlevels。ThusthickhazehaslainoverLondon,moreparticularlyoverthelowerparts,atsundown。Thenthroughnighthours,asthetemperatureofthelowerairhasbecomeequalised,thehazehascompletelydisappeared,butonlytoreassertitselfatdawn。

AdescriptionoftheveryimpressiveexperienceofanightsailoverLondonhasbeenreserved,butshouldnotbealtogetheromitted。Glaisher,writingofthespectacleasheobserveditnearlyfortyyearsago,describesLondonseenatnightfromaballoonatadistanceasresemblingavastconflagration。Whenactuallyoverthetown,amainthoroughfareliketheCommercialRoadshoneuplikealineofbrilliantfire;but,travellingwestward,OxfordStreetpresentedanappearancewhichpuzzledhim。"Herethetwothicklystuddedrowsofbrilliantlightswereseenoneithersideofthestreet,withanarrow,darkspacebetween,andthisdarkspacewasbounded,asitwere,onbothsidesbyabrightfringelikefrostedsilver。"Presentlyhediscoveredthatthisricheffectwascausedbythebrightilluminationoftheshoplightsonthepavements。"

London,asseenfromaballoononaclearmoonlightnightinAugustayearago(1901),woreasomewhatalteredappearance。

Therewerethefairylampstracingoutthestreets,which,thoughdarkcentred,woretheirsilverlining;butinirregularpatchesawhiterlightfromelectricarclampsbroadenedandbrightenedandshoneoutlikesomepyrotechnicdisplayabovetheblackhousetops。Throughthevasttownranablank,blackchannel,theriver,windingonintodistance,crossedhereandtherebybridgesshowingasbrightbands,andwithbrightspotsoccasionallytomarkwherelaytherivercraft。Butwhatwasmoststrikingwasthesilence。ThoughthenoiseofLondontrafficasheardfromaballoonhasdiminishedoflateyearsowingtothebetterpaving,yetindayhourstheroarofthestreetsishearduptoagreatheightasahard,harsh,grindingdin。Butatnight,afterthelast’bushasceasedtoply,andbeforethemarketcartsbeginlumberingin,theballoonist,ashesailsoverthetown,mightimaginethathewastraversingaCityoftheDead。

Itisatsuchtimesthatashoutthroughaspeakingtrumpethasamoststartlingeffect,andmoreparticularlyablastonahorn。Inthiscaseafteranintervalofsomesecondsawildnotewillbeflungbackfromthehouse—topsbelow,answeredandre—answeredonallsidesasitechoesfromrooftoroof——awild,weirduproarthatawakessuddenly,andthendiesoutslowlyfaraway。

Experimentswithechoesfromaballoonhaveprovedinstructive。

If,whenridingataheight,say,of2,000feet,achargeofgun—cottonbefiredelectrically100feetbelowthecar,thereport,thoughreallyasloudasacannon,soundsnomorethanamerepistolshot,possiblypartlyowingtothegreaterrarityoftheair,butchieflybecausethesound,havingnobackgroundtoreflectit,simplyspendsitselfintheair。Then,alwaysandunderallconditionsofatmospheresoever,thereensuesabsolutesilenceuntilthetimefortheechobackfromearthhasfullyelapsed,whenadeafeningoutburstofthunderrisesfrombelow,rollingonoftenformorethanhalfaminute。Twonoteworthyfacts,atleast,thewriterhasestablishedfromaverylargenumberoftrials:first,thatthetheoryofaerialechoesthrownbackfromemptyspace,whichphysicistshaveheldtoexistconstantly,andtobepartofthecauseofthunder,willhavetobeabandoned;and,secondly,thatfromsomecauseyettobefullyexplainedtheechobackfromtheearthisalwaysbehinditstime。

Butballoonshaverevealedfurthersuggestivefactswithregardtosound,andmoreparticularlywithregardtothevaryingacousticpropertiesoftheair。Itisafamiliarexperiencehowdistantsoundswillcomeandgo,risingandfalling,oftenbeingwaftedoverextraordinarydistances,andagainfailingaltogether,orsometimesbeinglostatnearrange,butappearinginstrengthfurtheraway。Afreeballoon,movingintheprofoundsilenceoftheupperair,becomesanadmirablesoundobservatory。Itmaybeclearlydetectedthatincertainconditionsofatmosphere,atleast,therearewhatmaybeconceivedtobeaerialsoundchannels,throughwhichsoundsare,momentarilyconveyedwithabnormalintensity。Thisphenomenondoesbutservetogiveanintelligiblepresentmentoftheunseenconditionsexistingintherealmofair。

Itwouldbereasonabletosupposethatwereaneyesoconstitutedastobeabletosee,say,cumulusmassesofwarmerair,stratamottledwithtracesofothergases,andbedsofinvisiblematterinsuspension,onemightsupposethatwhatwedeemtheclearestskywouldthenappearfleckedwithformsasmanyandvariousasthecloudsthatadornoursummerheavens。

Butthereismatterinsuspensionintheatmospherewhichisveryfarfrominvisible,andwhichinthecaseoflargetownsisverycommonlylyinginthickstrataoverhead,stoppingbackthesunlight,andformingthenucleusroundwhichnoisomefogsmayform。Experimentingwithsuitableapparatus,thewriterhasfoundonastillafternooninMay,at2,000feetaboveKingstoninSurrey,thattheairwaschargedfarmoreheavilywithdustthanthatoftheLondonstreetsthenextday;and,again,athalfamileabovethecityinthemonthofAugustlastdust,muchofitbeingofagrossandevenfibrousnature,wasfarmoreabundantthanongrassenclosuresinthetownduringtheforenoonofthedayfollowing。

AnattempthasbeenmadetoincludeEnglandinaseriesofinternationalballoonascentsarrangedexpresslyforthepurposeoftakingsimultaneousobservationsatalargenumberofstationsoverEurope,bywhichmeansitishopedthatmuchfreshknowledgewillbeforthcomingwithrespecttotheconstitutionoftheatmosphereuptothehighestlevelsaccessiblebyballoonsmannedandunmanned。ItisverymuchtoberegrettedthatinthecaseofEnglandtheattemptherespokenofhasrestedentirelyonprivateenterprise。FirstandforemostinpersonalliberalityandtheworkoforganisationmustbementionedMr。P。Y。Alexander,whosezealintheprogressofaeronauticsissecondtononeinthiscountry。

TwicethroughhiseffortsEnglandhasbeenrepresentedintheimportantworkforwhichContinentalnationshavenodifficultyinobtainingpublicgrants。ThefirstoccasionwasonNovember8th,1900,whenthewriterwasprivilegedtooccupyaseatintheballoonfurnishedbyMr。Alexander,andequippedwiththemostmoderntypeofinstruments。ItwasastormyandfastvoyagefromtheCrystalPalacetoHalstead,inEssex,48milesin40minutes。Simultaneouslywiththis,Mr。AlexanderdismissedanunmannedballoonfromBath,whichascended8,000

feet,andlandedatCricklade。OtherballoonswhichtookpartinthecombinedexperimentweretwofromParis,threefromChalaisMeudon,threefromStrasburg,twofromVienna,twofromBerlin,andtwofromSt。Petersburg。

Thesectionofourcountrymenspeciallyinterestedinaeronautics——agrowingcommunity——isrepresentedbytheAeronauticalSociety,formedin1865,withtheDukeofArgyllforpresident,andforthirtyyearsunderthemostenergeticmanagementofMr。F。W。Brearey,succeedingwhomashon。secs。

havebeenMajorBaden—PowellandMr。EricS。Bruce。Mr。

Breareywasoneofthemostsuccessfulinventorsofflyingmodels。Mr。Chanute,speakingasPresidentoftheAmericanSocietyofCivilEngineers,paidhimahighandwell—deservedcomplimentinsayingthatitwasthroughhisinfluencethataerialnavigationhadbeenclearedofmuchrubbishandplaceduponascientificandfirmbasis。

Anothercommunitydevotingitselftothepursuitofballoontripsandmattersaeronauticalgenerallyisthenewly—formedAeroClub,ofwhomoneofthemostprominentandenergeticmembersistheHon。C。S。Rolls。

IthadbeenannouncedthatM。Santos—DumontwouldbringanairshiptoEngland,andduringthesummerofthepresentyearwouldgiveexhibitionsofitscapability。ItwasevenrumouredthathemightcircleroundSt。Paul’sandaccomplishotheraerialfeatsunknowninEngland。ThepromisewasfulfilledsofarasbringingtheairshiptoEnglandwasconcerned,foroneofhisvesselswhichhadseenservicewasdepositedattheCrystalPalace。Insomemysteriousmanner,however,neversufficientlymadecleartothepublic,thismachinewasonemorningfounddamaged,andM。Santos—Dumonthaswithdrawnfromhisproposedengagements。

Inthusdoingheleftthefieldopentooneofourowncountrymen,who,inhisfirstattemptatflightwithanairshipofhisowninventionandconstruction,hasprovedhimselfnounworthyrivalofthewealthyyoungBrazilian。

Mr。StanleySpencer,inaverybriefspaceoftime,designedandbuiltcompletelyintheworkshopsofthefirmanelongatedmotorballoon,75feetlongby20feetdiameter,workedbyascrewandpetrolmotor。Thismotorisplacedintheprow,25

feetawayfrom,andinfrontof,thesafetyvalve,bywhichprecautionanydangerofignitingtheescapinggasisavoided。

Should,however,acollapseofthemachinearisefromanycause,thereisanarrangementforthrowingtheballoonintotheformofaparachute。Further,thereisprovidedmeansforadmittingairatwillintotheballoon,bywhichthenecessityformuchballastisobviated。

Mr。Spencerhavingfilledtheballoonwithpurehydrogen,madehisfirsttrialwiththismachinelateinaneveningattheendofJune。TheperformanceofthevesselisthusdescribedintheWestminsterGazette:——"Thehugeballoonfilledslowly,sothatthelightwasrapidlyfailingwhenatlastthedoorsofthebigshedslidopenandtheshipwasbroughtcarefullyout,hermotorstarted,andhermaidenvoyagecommenced。WithMr。

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