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按住Ctrl键单击鼠标打开配套教学视频名师讲课播放必修5Unit1JOHHSHOWDEFEATS“KINGCHOLERA”JohnSnowwasafamousdoctorinLondon-soexpert,indeed,thatheattendedQueenVictoriaasherpersonalphysician.Buthebecameinspiredwhenhethoughtabouthelpingordinarypeopleexposedtocholera.Thiswasthedeadlydiseaseofitsday.Neitheritscausenoritscurewasunderstood.Somanythousandsofterrifiedpeoplediedeverytimetherewasanoutbreak.JohnSnowwantedtofacethechallengeandsolvethisproblem.Heknewthatcholerawouldneverbecontrolleduntilitscausewasfound.Hebecameinterestedintwotheoriesthatpossiblyexplainedhowcholerakilledpeople.Thefirstsuggestedthatcholeramultipliedintheair.Acloudofdangerousgasfloatedarounduntilitfounditsvictims.Thesecondsuggestedthatpeopleabsorbedthisdiseaseintotheirbodieswiththeirmeals.Fromthestomachthediseasequicklyattackedthebodyandsoontheaffectedpersondied.JohnSnowsuspectedthatthesecondtheorywascorrectbutheneededevidence.SowhenanotheroutbreakhitLondonin1854,hewasreadytobeginhisenquiry.Asthediseasespreadquicklythroughpoorneighbourhoods,hebegantogatherinformation.Intwoparticularstreets,thecholeraoutbreakwassoseverethatmorethan500peoplediedintendays.Hewasdeterminedtofindoutwhy.Firsthemarkedonamaptheexactplaceswhereallthedeadpeoplehadlived.Thisgavehimavaluableclueaboutthecauseofthedisease.ManyofthedeathswerenearthewaterpumpinBroadStreet(especiallynumbers16,37,38and40).Healsonoticedthatsomehouses(suchas20and21BroadStreetand8and9CambridgeStreet)hadhadnodeaths.Hehadnotforeseenthis,sohemadefurtherinvestigations.Hediscoveredthatthesepeopleworkedinthepubat7CambridgeStreet.Theyhadbeengivenfreebeerandsohadnotdrunkthewaterfromthepump.Itseemedthatthewaterwastoblame.Next,JohnSnowlookedintothesourceofthewaterforthesetwostreets.HefoundthatitcamefromtheriverpollutedbythedirtywaterfromLondon.HeimmediatelytoldtheastonishedpeopleinBroadStreettoremovethehandlefromthepumpsothatitcouldnotbeused.Soonafterwardsthediseasesloweddown.Hehadshownthatcholerawasspreadbygermsandnotinacloudofgas.InanotherpartofLondon,hefoundsupportingevidencefromtwootherdeathsthatwerelinkedtotheBroadStreetoutbreak.Awoman,whohadmovedawayfromBroadStreet,likedthewaterfromthepumpsomuchthatshehaditdeliveredtoherhouseeveryday.Bothsheandherdaughterdiedofcholeraafterdrinkingthewater.WiththisextraevidenceJohnSnowwasabletoannouncewithcertaintythatpollutedwatercarriedthevirus.Topreventthisfromhappeningagain,JohnSnowsuggestedthatthesourceofallthewatersuppliesbeexamined.Thewatercompanieswereinstructednottoexposepeopletopollutedwateranymore.FinallyKingCholerawasdefeated.COPERNICUS’REVOLUTIONRRYTHEORYNicolausCopernicuswasfrightenedandhismindwasconfused.Althoughhehadtriedtoignorethem,allhismathematicalcalculationsledtothesameconclusion:thattheearthwasnotthecentreofthesolarsystem.Onlyifyouputthesuntheredidthemovementsoftheotherplanetsintheskymakesense.YethecouldnottellanyoneabouthistheoryasthepowerfulChristianChurchwouldhavepunishedhimforevensuggestingsuchanidea.TheybelievedGodhadmadetheworldandforthatreasontheearthwasspecialandmustbethecentreofthesolarsystem.Theproblemarosebecauseastronomershadnoticedthatsomeplanetsintheskyseemedtostop,movebackwardandthengoforwardinaloop.Othersappearedbrighterattimesandlessbrightatothers.Thiswasverystrangeiftheearthwasthecentreofthesolarsystemandallplanetswentroundit.Copernicushadthoughtlongandhardabouttheseproblemsandtriedtofindananswer.Hehadcollectedobservationsofthestarsandusedallhismathematicalknowledgetoexplainthem.Butonlyhisnewtheorycoulddothat.Sobetween1510and1514heworkedonit,graduallyimprovinghistheoryuntilhefeltitwascomplete.In1514heshoweditprivatelytohisfriends.Thechangeshemadetotheoldtheorywererevolutionary.Heplacedafixedsunatthecentreofthesolarsystemwiththeplanetsgoingrounditandonlythemoonstillgoingroundtheearth.Healsosuggestedthattheearthwasspinningasitwentroundthesunandthisexplainedchangesinthemovementoftheplanetsandinthebrightnessofthestars.Hisfriendswereenthusiasticandencouragedhimtopublishhisideas,butCopernicuswascautious.HedidnotwanttobeattackedbytheChristianChurch,soheonlypublisheditashelaydyingin1543.Certainlyhewasrighttobecareful.TheChristianChurchrejectedhistheory,sayingitwasagainstGod'sideaandpeoplewhosupporteditwouldbeattacked.YetCopernicus'theoryisnowthebasisonwhichallourideasoftheuniversearebuilt.HistheoryreplacedtheChristianideaofgravity,whichsaidthingsfelltoearthbecauseGodcreatedtheearthasthecentreoftheuniverse.Copernicusshowedthiswasobviouslywrong.NowpeoplecanseethatthereisadirectlinkbetweenhistheoryandtheworkofIsaacNewton,AlbertEinsteinandStephenHawking.必修5Unit2PUZZLESINGEOGRAPHYPeoplemaywonderwhydifferentwordsareusedtodescribethesefourcountries:England,Wales,ScotlandandNorthernIreland.YoucanclarifythisquestionifyoustudyBritishhistory.FirsttherewasEngland.Waleswaslinkedtoitinthethirteenthcentury.NowwhenpeoplerefertoEnglandyoufindWalesincludedaswell.NextEnglandandWaleswerejoinedtoScotlandintheseventeenthcenturyandthenamewaschangedtoGreatBritain.HappilythiswasaccomplishedwithoutconflictwhenKingJamesofScotlandbecameKingofEnglandandWalesaswell.FinallytheEnglishgovernmen