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Johnsnowdefeats“kingcholera”
Johnsnowwasafamousdoctorinlondon-soexpert,indeed,thatheattendedqueenvictoraasherpersonalphysician.buthebecameinspiredwhenhethoughtabouthelpingordinarypeopleexposedtocholera.thiswasthedeadlydiseaseofitsday.neitheritscausenoritscurewasunderstood.somanythousandsofterrifiedpeoplediedeverytimetherewasanoutbreak.Johnsnowwantedtofacethechallengeandsolvethisproblem.heknewthatcholerawouldneverbecontrolleduntilitscausewasfound.
Hebecameinsterestedintwotheoriesthatpoissiblyexplainedhowcholerakilledpeople.thefirstsuggestedthatcholeramultipliedintheair.acloudofdangerousgasfloatedarounduntilitfounditsvictim.thesecondsuggestedthatpeopleabsorbedthesediseaseintotheirbodieswiththeirmeals.fromthestomachthediseasequicklyattackedthebodyandsoontheaffectedpersondied.
Johnsnowsuspectedthatthesecondtheorywascorrectbutheneededevidence.sowhenanotheroutbreakhitlondonin1854,hewasreadytobeginhisenquire.asthediseasequicklyspreadthroughpoorneighbourhoods,hebegantogatherinformation.intwoparticularstreets,thecholeraoutbreakwassoseverethatmorethan500peoplediedintendays.hewasdeterminedtofindoutwhy.
Firsthemarkedonamaptheexactplaceswhereallthediedpeoplehadlived.Thisgavehimavaluableclueaboutthecauseofthedisease.manyofthedeathswerenearthewaterpumpinbroadstreet.healsonoticedthatsomehouseshadhadnodeath.hehadnotforeseenthis,sohemadefurtherinvestigations,hediscoveredthatthesepeopleworkedinthepubat7cambridgestreet.theyhadbeengivenfreebeerandsohadnotdrunkthewaterfromthepunp.itseemedthatthewaterwastoblame.
Next,johnsnowlookintothesourceofthewaterforthesetwostreets.hefoundthatitcamefromtheriverpollutedbythedirtywaterfromlondon.heimmediatelytoldtheastonishedpeopleinbroadstreettoremovethehandlefromthepumpsothatitcouldnotbeused.soonafterwordsthediseasesloweddown.hehadshownthatcholerawasspreadbygermsandnotinacloudofgas.
Inanotherpartoflondon,hefoundsupportingevidencefromtwootherdeathsthatwerelinkedtothebr