高中课文 高中英语必修5

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1、Unit1GreatscientistsReadingJOHNSNOWDEFEATS“KINGCHOLERA”JohnSnowwasawell-knowndoctorinLondon-sofamous,indeed,thatheattendedQueenVictoriatoeasethebirthofherbabies.Buthebecameinspiredwhenhethoughtabouthelpingordinarypeopleexposedtocholera.Thiswasthemostdeadlydisease

2、ofitsday.Neitheritscause,noritscurewasunderstood.Somanythousandsofterrifiedpeoplediedeverytimetherewasanoutbreak.JohnSnowwantedtousehisknowledgetohelpsolvethisproblem.Heknewitwouldheverbecontrolleduntilitscausewasfound.Hegotinterestedintwotheoriesexplaininghowcho

3、lerakilledpeople.Thefirstsuggestedthatcholeramultipliedintheairwithoutreason.Acloudofdangerousgaswouldfloatarounduntilitfounditsvictims.Thesecondsuggestedthatpeopleabsorbedthisdiseaseintotheirbodieswiththeirmeals.Fromthestomachthediseaseattackedthebodyquicklyands

4、oontheaffectedpersonwasdead.Hebelievedinthesecondtheorybutneededtoprovehewascorrect.SowhenanotheroutbreakhitLondonin1854,JohnSnowwasreadytotestthesetwotheories.Asthediseasespreadquicklythroughthepoorneighbourhoods,JohnSnowbegantogathertheinformation.Hefoundthatin

5、twoparticularstreets,thecholeraoutbreakwassoseverethatmorethan500peoplehaddiedin10days.Hedeterminedtofindoutwhy.Hemarkedonamapwhereallthedeadpeoplehadlived.Hereitis:Themapgaveavaluableclueaboutthecauseofthedisease.ManyofthedeathswerenearthewaterpumpinBroadStreet(

6、especiallynumbers16,37,38and40BroadStreet).JohnSnowalsosawthatsomehouses(suchas20and21BroadStreetand8and9CambridgeStreet)hadhadnodeaths.Hediscoveredthatthesefamiliesworkedinthepubat7CambridgeStreet.TheyweregivenfreebeerandsohadnotdrunkthewaterfromtheBroadStreetpu

7、mp.Itseemedthewaterwastoblame.Next,JohnSnowlookedintothesourceofthewaterforthesetwostreets.Hefoundthatitcamefromtheriver,whichhadbeenpollutedbythedirtywaterfromLondon.ImmediatelyJohnSnowtoldtheastonishedpeopleinBroadStreettoremovethehandlefromthewaterpumpsoitcoul

8、dnotbeused.Soonthediseasebegantoslowdown.JohnSnowhadshownthatcholerawasspreadbygermsandnotinacloudofgas.Inaddition,hefoundtwootherdeathsinanotherpartofLondonth