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Hebeganhistalkbygivingaconcisedefinitionofpost-modernism.
Animals’"SixthSense" AtsunamiwastriggeredbyanearthquakeintheIndianOceaninDecember2004.ItkilledtensofthousandsofpeopleinAsiaandEastAfrica.Wildanimals51seemtohaveescapedthatterribletsunami.Thisphenomenonaddsweighttonotionsthattheypossessa"sixthsense"for52expertssaid. SriLankanwildlifeofficialshavesaidthegiantwavesthatkilledover24000peoplealongtheIndianOceanisland’scoastclearly53wildbeastswithnodeadanimalsfound. "Noelephantsaredeadnot54adeadrabbit.Ithinkanimalscan55disaster.Theyhaveasixthsense.Theyknowwhenthingsarehappening"H.D.RatnayakedeputydirectorofSriLanka’sWildlifeDepartmentsaidaboutonemonthafterthetsunamiattack.The56washedfloodwatersupto2milesinlandatYalaNationalParkintheravagedsoutheastSriLanka’sbiggestwildlife57andhometohundredsofwildelephantsandseveralleopards. "Therehasbeenalotof58evidenceaboutdogsbarkingorbirdsmigratingbeforevolcaniceruptionsorearthquakes.Butithasnotbeenproven"saidMatthewvanLieropananimalbehavior59atJohannesburgZoo. "Therehavebeenno60studiesbecauseyoucan’treallytestitinalaborfieldsetting"hetoldReuters.Otherauthoritiesconcurredwiththis61. "Wildlifeseemtobeabletopickupcertain62especiallybirds...therearemanyreportsofbirdsdetectingimpendingdisasters"saidCliveWalkerwhohaswrittenseveralbooksonAfricanwildlife.Animals63relyontheknownsensessuchassmellorhearingtoavoiddangersuchaspredators. Thenotionofananimal"sixthsense"—or64othermythicalpowerisanenduringonewhichtheevidenceonSriLanka’sravagedcoastislikelytoaddto. TheRomanssawowls65omensofimpendingdisasterandmanyancientculturesviewedelephantsassacredanimalsendowedwithspecialpowerorattributes. 58
{{*HTML*}}AdultEducation??1.Voluntarylearninginorganizedcoursesbymaturemenandwomeniscalledadulteducation.Sucheducationisofferedtomakepeopleabletoenlargeandinterprettheirexperienceasadults.Adultsmaywanttostudysomethingwhichtheymissedinearlierschoolinggetnewskillsorjobtrainingfindoutaboutnewtechnologicaldevelopmentsseekbetterself-understandingordevelopnewtalentsandskills.??2.Thiskindofeducationmaybeintheformofself-studywithproperguidancethroughtheuseoflibrariescorrespondencecoursesorbroadcasting.Itmayalsobeacquiredcollectivelyinschoolsandcollegesstudygroupsworkshopsclubsandprofessionalassociations.??3.Modernadulteducationforlargenumbersofpeoplestartedinthe18thand19thcenturieswiththeriseoftheIndustrialRevolution.Greateconomicandsocialchangesweretakingplace;peopleweremovingfromruralareastocities;newtypesofworkwerebeingcreatedinanexpandingfactorysystem.Theseandotherfactorsproducedaneedforfurthereducationandre-educationofadults.??4.TheearliestprogramsoforganizedadulteducationaroseinGreatBritaininthe1790swiththefoundingofanadultschoolinNottinghamandamechanicsinstitutioninGlasgow.BenjaminFranklinandsomefriendsfoundtheearliestadulteducationinstitutionintheU.S.inPhiladelphiain1727.??5.Peoplerecognizethatcontinuedlearningisnecessaryformostformsofemploymenttoday.Forexamplepartsoftheadultpopulationinmanycountriesfinditnecessarytotakepartinretrainingprogramsatworkoreventolearncompletelynewjobs.Adulteducationprogramsarespringingupconstantlytomeettheseandotherneeds.Paragraph5______
Animals’"SixthSense" AtsunamiwastriggeredbyanearthquakeintheIndianOceaninDecember2004.ItkilledtensofthousandsofpeopleinAsiaandEastAfrica.Wildanimals51seemtohaveescapedthatterribletsunami.Thisphenomenonaddsweighttonotionsthattheypossessa"sixthsense"for52expertssaid. SriLankanwildlifeofficialshavesaidthegiantwavesthatkilledover24000peoplealongtheIndianOceanisland’scoastclearly53wildbeastswithnodeadanimalsfound. "Noelephantsaredeadnot54adeadrabbit.Ithinkanimalscan55disaster.Theyhaveasixthsense.Theyknowwhenthingsarehappening"H.D.RatnayakedeputydirectorofSriLanka’sWildlifeDepartmentsaidaboutonemonthafterthetsunamiattack.The56washedfloodwatersupto2milesinlandatYalaNationalParkintheravagedsoutheastSriLanka’sbiggestwildlife57andhometohundredsofwildelephantsandseveralleopards. "Therehasbeenalotof58evidenceaboutdogsbarkingorbirdsmigratingbeforevolcaniceruptionsorearthquakes.Butithasnotbeenproven"saidMatthewvanLieropananimalbehavior59atJohannesburgZoo. "Therehavebeenno60studiesbecauseyoucan’treallytestitinalaborfieldsetting"hetoldReuters.Otherauthoritiesconcurredwiththis61. "Wildlifeseemtobeabletopickupcertain62especiallybirds...therearemanyreportsofbirdsdetectingimpendingdisasters"saidCliveWalkerwhohaswrittenseveralbooksonAfricanwildlife.Animals63relyontheknownsensessuchassmellorhearingtoavoiddangersuchaspredators. Thenotionofananimal"sixthsense"—or64othermythicalpowerisanenduringonewhichtheevidenceonSriLanka’sravagedcoastislikelytoaddto. TheRomanssawowls65omensofimpendingdisasterandmanyancientculturesviewedelephantsassacredanimalsendowedwithspecialpowerorattributes. 56
Itissaidthatthehousesalongthisstreetwillsoonbedemolished.
{{*HTML*}}AdultEducation??1.Voluntarylearninginorganizedcoursesbymaturemenandwomeniscalledadulteducation.Sucheducationisofferedtomakepeopleabletoenlargeandinterprettheirexperienceasadults.Adultsmaywanttostudysomethingwhichtheymissedinearlierschoolinggetnewskillsorjobtrainingfindoutaboutnewtechnologicaldevelopmentsseekbetterself-understandingordevelopnewtalentsandskills.??2.Thiskindofeducationmaybeintheformofself-studywithproperguidancethroughtheuseoflibrariescorrespondencecoursesorbroadcasting.Itmayalsobeacquiredcollectivelyinschoolsandcollegesstudygroupsworkshopsclubsandprofessionalassociations.??3.Modernadulteducationforlargenumbersofpeoplestartedinthe18thand19thcenturieswiththeriseoftheIndustrialRevolution.Greateconomicandsocialchangesweretakingplace;peopleweremovingfromruralareastocities;newtypesofworkwerebeingcreatedinanexpandingfactorysystem.Theseandotherfactorsproducedaneedforfurthereducationandre-educationofadults.??4.TheearliestprogramsoforganizedadulteducationaroseinGreatBritaininthe1790swiththefoundingofanadultschoolinNottinghamandamechanicsinstitutioninGlasgow.BenjaminFranklinandsomefriendsfoundtheearliestadulteducationinstitutionintheU.S.inPhiladelphiain1727.??5.Peoplerecognizethatcontinuedlearningisnecessaryformostformsofemploymenttoday.Forexamplepartsoftheadultpopulationinmanycountriesfinditnecessarytotakepartinretrainingprogramsatworkoreventolearncompletelynewjobs.Adulteducationprogramsarespringingupconstantlytomeettheseandotherneeds.Paragraph3______
Animals’"SixthSense" AtsunamiwastriggeredbyanearthquakeintheIndianOceaninDecember2004.ItkilledtensofthousandsofpeopleinAsiaandEastAfrica.Wildanimals51seemtohaveescapedthatterribletsunami.Thisphenomenonaddsweighttonotionsthattheypossessa"sixthsense"for52expertssaid. SriLankanwildlifeofficialshavesaidthegiantwavesthatkilledover24000peoplealongtheIndianOceanisland’scoastclearly53wildbeastswithnodeadanimalsfound. "Noelephantsaredeadnot54adeadrabbit.Ithinkanimalscan55disaster.Theyhaveasixthsense.Theyknowwhenthingsarehappening"H.D.RatnayakedeputydirectorofSriLanka’sWildlifeDepartmentsaidaboutonemonthafterthetsunamiattack.The56washedfloodwatersupto2milesinlandatYalaNationalParkintheravagedsoutheastSriLanka’sbiggestwildlife57andhometohundredsofwildelephantsandseveralleopards. "Therehasbeenalotof58evidenceaboutdogsbarkingorbirdsmigratingbeforevolcaniceruptionsorearthquakes.Butithasnotbeenproven"saidMatthewvanLieropananimalbehavior59atJohannesburgZoo. "Therehavebeenno60studiesbecauseyoucan’treallytestitinalaborfieldsetting"hetoldReuters.Otherauthoritiesconcurredwiththis61. "Wildlifeseemtobeabletopickupcertain62especiallybirds...therearemanyreportsofbirdsdetectingimpendingdisasters"saidCliveWalkerwhohaswrittenseveralbooksonAfricanwildlife.Animals63relyontheknownsensessuchassmellorhearingtoavoiddangersuchaspredators. Thenotionofananimal"sixthsense"—or64othermythicalpowerisanenduringonewhichtheevidenceonSriLanka’sravagedcoastislikelytoaddto. TheRomanssawowls65omensofimpendingdisasterandmanyancientculturesviewedelephantsassacredanimalsendowedwithspecialpowerorattributes. 52
Animals’"SixthSense" AtsunamiwastriggeredbyanearthquakeintheIndianOceaninDecember2004.ItkilledtensofthousandsofpeopleinAsiaandEastAfrica.Wildanimals51seemtohaveescapedthatterribletsunami.Thisphenomenonaddsweighttonotionsthattheypossessa"sixthsense"for52expertssaid. SriLankanwildlifeofficialshavesaidthegiantwavesthatkilledover24000peoplealongtheIndianOceanisland’scoastclearly53wildbeastswithnodeadanimalsfound. "Noelephantsaredeadnot54adeadrabbit.Ithinkanimalscan55disaster.Theyhaveasixthsense.Theyknowwhenthingsarehappening"H.D.RatnayakedeputydirectorofSriLanka’sWildlifeDepartmentsaidaboutonemonthafterthetsunamiattack.The56washedfloodwatersupto2milesinlandatYalaNationalParkintheravagedsoutheastSriLanka’sbiggestwildlife57andhometohundredsofwildelephantsandseveralleopards. "Therehasbeenalotof58evidenceaboutdogsbarkingorbirdsmigratingbeforevolcaniceruptionsorearthquakes.Butithasnotbeenproven"saidMatthewvanLieropananimalbehavior59atJohannesburgZoo. "Therehavebeenno60studiesbecauseyoucan’treallytestitinalaborfieldsetting"hetoldReuters.Otherauthoritiesconcurredwiththis61. "Wildlifeseemtobeabletopickupcertain62especiallybirds...therearemanyreportsofbirdsdetectingimpendingdisasters"saidCliveWalkerwhohaswrittenseveralbooksonAfricanwildlife.Animals63relyontheknownsensessuchassmellorhearingtoavoiddangersuchaspredators. Thenotionofananimal"sixthsense"—or64othermythicalpowerisanenduringonewhichtheevidenceonSriLanka’sravagedcoastislikelytoaddto. TheRomanssawowls65omensofimpendingdisasterandmanyancientculturesviewedelephantsassacredanimalsendowedwithspecialpowerorattributes. 60
SeeingtheWorldCenturiesAgo IfyouenjoylookingthroughtravelbooksbysuchfamiliarauthorsasArthurFormerorEugeneFodoritwillnotsurpriseyoutoleanthattravelwritinghasalongandvenerablehistory.Almostfromtheearliestannalsofrecordedtimeindividualshavefoundreadyaudiencesfortheiraccountsofjourneystostrangeandexoticlocales. OneoftheearliesttravelwritersaGreekgeographerandhistoriannamedStrabolivedaroundthetimeofChrist.ThoughStraboisknowntohavetraveledfromeastoftheBlackSeawesttoItalyandasfarsouthasEthiopiahealsouseddetailsgleanedfromotherwriterstoextendandenlivenhisaccounts.HismultivolumedworkGeographyprovidestheonlysurvivingaccountofthecitiespeoplescustomsandgeographicalpeculiaritiesofthewholeknownworldofhistime. TwootherclassictravelwriterstheItalianMarcoPoloandtheMoroccanIbnBattutahlivedinroughlythesametimeperiod.MarcoPolotraveledtoChinawithhisfatheranduncleinaboutA.D.1275andremainedthere16or17yearsvisitingseveralothercountriesduringhistravels.WhenMarcoreturnedtoItalyhedictatedhismemoirsincludingstorieshehadheardfromotherstoascribewiththeresultingbookThemillionbeinganinstantsuccess.ThoughdifficulttoattesttotheaccuracyofallhesaysMarco’sbookimpelledEuropeanstobegintheirgreatvoyagesofexploration. IbnBattutah’sinterestintravelbeganonhisrequiredMuslimjourneytoMeccain1325andduringhislifetimehejourneyedthroughallthecountrieswhereIslamheldsway.HistravelbooktheRihlahisapersonalizedaccountofdesertjourneyscourtintriguesandeventheeffectoftheBlackDeathinthevariouslandshevisited.Inalmost30yearsoftravelingitisestimatedthatIbnBattutahcoveredmorethan75000miles. Theoverallorganizationofthispassageisthrough.
{{*HTML*}}AdultEducation??1.Voluntarylearninginorganizedcoursesbymaturemenandwomeniscalledadulteducation.Sucheducationisofferedtomakepeopleabletoenlargeandinterprettheirexperienceasadults.Adultsmaywanttostudysomethingwhichtheymissedinearlierschoolinggetnewskillsorjobtrainingfindoutaboutnewtechnologicaldevelopmentsseekbetterself-understandingordevelopnewtalentsandskills.??2.Thiskindofeducationmaybeintheformofself-studywithproperguidancethroughtheuseoflibrariescorrespondencecoursesorbroadcasting.Itmayalsobeacquiredcollectivelyinschoolsandcollegesstudygroupsworkshopsclubsandprofessionalassociations.??3.Modernadulteducationforlargenumbersofpeoplestartedinthe18thand19thcenturieswiththeriseoftheIndustrialRevolution.Greateconomicandsocialchangesweretakingplace;peopleweremovingfromruralareastocities;newtypesofworkwerebeingcreatedinanexpandingfactorysystem.Theseandotherfactorsproducedaneedforfurthereducationandre-educationofadults.??4.TheearliestprogramsoforganizedadulteducationaroseinGreatBritaininthe1790swiththefoundingofanadultschoolinNottinghamandamechanicsinstitutioninGlasgow.BenjaminFranklinandsomefriendsfoundtheearliestadulteducationinstitutionintheU.S.inPhiladelphiain1727.??5.Peoplerecognizethatcontinuedlearningisnecessaryformostformsofemploymenttoday.Forexamplepartsoftheadultpopulationinmanycountriesfinditnecessarytotakepartinretrainingprogramsatworkoreventolearncompletelynewjobs.Adulteducationprogramsarespringingupconstantlytomeettheseandotherneeds.Theearliestorganizedadulteducationoriginatedin______
ComputerMouse Thebasiccomputermouseisanamazinglycleverinventionwitharelativelysimpledesignthatallowsustopointatthingsonthecomputeranditisveryproductive.Thinkofallthethingsyoucandowithamouselikeselectingtextforcopyingandpastingdrawingandevenscrollingonthepagewiththenewermicewiththewheel.Mostofususethecomputermousedailywithoutstoppingtothinkhowitworksuntilitgetsdirtyandwehavetolearnhowtocleanit.Welearntopointatthingsbeforewelearntospeaksothemouseisaverynaturalpointingdevice.Othercomputerpointingdevicesincludelightpensgraphicstabletsandtouchscreensbutthemouseisstillourworkhorse. Thecomputermousewasinventedin1964byDouglasEnglehartofStanfordUniversity.Ascomputerscreensbecamemorepopularandarrowkeyswereusedtomovearoundabodyoftextitbecameclearthatapointingdevicethatallowedeasiermotionthroughthetextandevenselectionoftextwouldbeveryuseful.TheintroductionofthemousewiththeAppleLisacomputerin1983reallystartedthecomputerpublicontheroadtorelyingonthemouseforroutinecomputertasks. HowdoesthemouseworkWehavetostartatthebottomsothinkupsidedownfornow.Itallstartswiththemouseball.Asthemouseballinthebottomofthemouserollsoverthemousepaditpressesagainstandturnstwoshafts.Theshaftsareconnectedtowheelswithseveralsmallholesinthem.Thewheelshaveapairofsmallelectroniclight-emittingdevicescalledlight-emittingdiodesLEDmountedoneitherside.OneLEDsendsalightbeamtotheLEDontheotherside.AsthewheelsspinandaholerotatesbythelightbeamgetsthroughtotheLEDontheotherside.Butamomentlaterthelightbeamisblockeduntilthenextholeisinplace.TheLEDdetectsachangingpatternoflightconvertsthepatternintoanelectronicsignalandsendsthesignaltothecomputerthroughwiresinacablethatgoesoutofthemousebody.Thiscableisthetailthathelpsgivethemouseitsname.Thecomputerinterpretsthesignaltotellitwheretopositionthecursoronthecomputerscreen. Sofarwehaveonlydiscussedthebasiccomputermousethatmostofyouprobablyhaveorhaveused.Oneproblemwiththisdesignisthatthemousegetsdirtyastheballrollsoverthesurfaceandpicksupdirt.Eventuallyyouhavetocleanyourmouse.Theneweropticalmiceavoidthisproblembyhavingnomovingparts. Thecomputermousederivesitsnamefromthecablethatgoesoutitsbodywhichlookslikethetailofamouse.
{{*HTML*}}AdultEducation??1.Voluntarylearninginorganizedcoursesbymaturemenandwomeniscalledadulteducation.Sucheducationisofferedtomakepeopleabletoenlargeandinterprettheirexperienceasadults.Adultsmaywanttostudysomethingwhichtheymissedinearlierschoolinggetnewskillsorjobtrainingfindoutaboutnewtechnologicaldevelopmentsseekbetterself-understandingordevelopnewtalentsandskills.??2.Thiskindofeducationmaybeintheformofself-studywithproperguidancethroughtheuseoflibrariescorrespondencecoursesorbroadcasting.Itmayalsobeacquiredcollectivelyinschoolsandcollegesstudygroupsworkshopsclubsandprofessionalassociations.??3.Modernadulteducationforlargenumbersofpeoplestartedinthe18thand19thcenturieswiththeriseoftheIndustrialRevolution.Greateconomicandsocialchangesweretakingplace;peopleweremovingfromruralareastocities;newtypesofworkwerebeingcreatedinanexpandingfactorysystem.Theseandotherfactorsproducedaneedforfurthereducationandre-educationofadults.??4.TheearliestprogramsoforganizedadulteducationaroseinGreatBritaininthe1790swiththefoundingofanadultschoolinNottinghamandamechanicsinstitutioninGlasgow.BenjaminFranklinandsomefriendsfoundtheearliestadulteducationinstitutionintheU.S.inPhiladelphiain1727.??5.Peoplerecognizethatcontinuedlearningisnecessaryformostformsofemploymenttoday.Forexamplepartsoftheadultpopulationinmanycountriesfinditnecessarytotakepartinretrainingprogramsatworkoreventolearncompletelynewjobs.Adulteducationprogramsarespringingupconstantlytomeettheseandotherneeds.Therearevariousformsofadulteducationincluding______
ComputerMouse Thebasiccomputermouseisanamazinglycleverinventionwitharelativelysimpledesignthatallowsustopointatthingsonthecomputeranditisveryproductive.Thinkofallthethingsyoucandowithamouselikeselectingtextforcopyingandpastingdrawingandevenscrollingonthepagewiththenewermicewiththewheel.Mostofususethecomputermousedailywithoutstoppingtothinkhowitworksuntilitgetsdirtyandwehavetolearnhowtocleanit.Welearntopointatthingsbeforewelearntospeaksothemouseisaverynaturalpointingdevice.Othercomputerpointingdevicesincludelightpensgraphicstabletsandtouchscreensbutthemouseisstillourworkhorse. Thecomputermousewasinventedin1964byDouglasEnglehartofStanfordUniversity.Ascomputerscreensbecamemorepopularandarrowkeyswereusedtomovearoundabodyoftextitbecameclearthatapointingdevicethatallowedeasiermotionthroughthetextandevenselectionoftextwouldbeveryuseful.TheintroductionofthemousewiththeAppleLisacomputerin1983reallystartedthecomputerpublicontheroadtorelyingonthemouseforroutinecomputertasks. HowdoesthemouseworkWehavetostartatthebottomsothinkupsidedownfornow.Itallstartswiththemouseball.Asthemouseballinthebottomofthemouserollsoverthemousepaditpressesagainstandturnstwoshafts.Theshaftsareconnectedtowheelswithseveralsmallholesinthem.Thewheelshaveapairofsmallelectroniclight-emittingdevicescalledlight-emittingdiodesLEDmountedoneitherside.OneLEDsendsalightbeamtotheLEDontheotherside.AsthewheelsspinandaholerotatesbythelightbeamgetsthroughtotheLEDontheotherside.Butamomentlaterthelightbeamisblockeduntilthenextholeisinplace.TheLEDdetectsachangingpatternoflightconvertsthepatternintoanelectronicsignalandsendsthesignaltothecomputerthroughwiresinacablethatgoesoutofthemousebody.Thiscableisthetailthathelpsgivethemouseitsname.Thecomputerinterpretsthesignaltotellitwheretopositionthecursoronthecomputerscreen. Sofarwehaveonlydiscussedthebasiccomputermousethatmostofyouprobablyhaveorhaveused.Oneproblemwiththisdesignisthatthemousegetsdirtyastheballrollsoverthesurfaceandpicksupdirt.Eventuallyyouhavetocleanyourmouse.Theneweropticalmiceavoidthisproblembyhavingnomovingparts. Whenanordinarycomputermousegetsdirtyithastobereplacedwithanewone.
{{*HTML*}}LudwigVanBeethoven??LudwigvanBeethovenamajorcomposerofthenineteenthcenturyovercamemanypersonalproblemstoachieveartisticgreatness.??BorninBonnGermanyin1770hefirststudiedmusicwiththecourtorganistGillesvanderEeden.Hisfatherwasexcessivelystrictandgiventoheavydrinking.?46?AppointeddeputycourtorganisttoChristianGottlobNeefeatasurprisinglyearlyagein1782Beethovenalsoplayedtheharpsichordandtheviola.In1792hewassenttoViennabyhispatronCountFerdinandWaldsteintostudymusicunderHaydn.??Beethovenremainedunmarried.?47?Continuallyplaguedbyillhealthhedevelopedanearinfectionwhichledtohistragicdeafnessin1819.???48?Hecompletedmaturemasterpiecesofgreatmusicaldepth:threepianosonatasfourstringquartetstheMissaSolemnisandthe9thSymphony.Hediedin1827.?49???NotingthatBeethovenoftenflewintofitsofrageGoetheoncesaidofhimIamastonishedbyhistalentbutheisunfortunatelyanaltogetheruntamedpersonality.?50????A.Inspiteofthishandicaphoweverhecontinuedtowritemusic.???B.Becauseofirregularpaymentsfromhispublishersanderraticsupportfromhispatronshewastroubledbyfinancialworriesthroughouthisadultlife.???C.Hislifewasmarkedbyapassionatededicationtoindependence.??D.WhenhismotherdiedBeethoventhenayoungmanwasnamedguardianofhistwoyoungerbrothers.??E.AlthoughBeethoven’spersonalitymayhavebeenuntamedhismusicshowsgreatdisciplineandcontrolandthisishowwerememberhimbest.??F.Todayhismusicisstillbeingplayedallovertheworld.
TheCherokeeNation LongbeforethewhitemancametoAmericathelandbelongedtotheAmericanIndiannations.ThenationoftheCherokeeslivedinwhatisnowthesoutheasternpartoftheUnitedStates. AfterthewhitemancametheCherokeescopiedmanyoftheirways.OneCherokeenamedSequoyahsawhowimportantreadingandwritingwastothewhiteman.HedecidedtoinventawaytowritedownthespokenCherokeelanguage.Hebeganbymakingwordpictures.Foreachwordhedrewapicture.Butthatprovedimpossible—therewerejusttoomanywords.Thenhetookthe85soundsthatmadeupthelanguage.UsinghisownimaginationandanEnglishspellingbookSequoyahinventedasignforeachsound.Hisalphabetprovedamazinglyeasytolearn.BeforelongmanyCherokeesknewhowtoreadandwriteintheirownlanguage.By1828theywereevenprintingtheirownnewspaper. In1830theUSCongresspassedalaw.ItallowedthegovernmenttoremoveIndiansfromtheirlands.TheCherokeesrefusedtogo.Theyhadlivedontheirlandsforcenturies.Itbelongedtothem.WhyshouldtheygotoastrangelandfarbeyondtheMississippiRiver ThearmywassenttodrivetheCherokeesout.Soldierssurroundedtheirvillagesandmarchedthematgunpointintothewesternterritory.Thesicktheoldandthesmallchildrenwentincartsalongwiththeirbelongings.Therestofthepeoplemarchedonfootorrodeonhorseback.ItwasNovemberyetmanyofthemstillworetheirsummerclothes.ColdandhungrytheCherokeeswerequicklyexhaustedbythehardshipsofthejourney.Manydroppeddeadandwereburiedbytheroadside.WhenthelastgrouparrivedintheirnewhomeinMarch1839morethan4000haddied.Itwasindeedamarchofdeath. ManyCherokeesdiedontheirwaytotheirnewhomemainlybecause.
{{*HTML*}}LudwigVanBeethoven??LudwigvanBeethovenamajorcomposerofthenineteenthcenturyovercamemanypersonalproblemstoachieveartisticgreatness.??BorninBonnGermanyin1770hefirststudiedmusicwiththecourtorganistGillesvanderEeden.Hisfatherwasexcessivelystrictandgiventoheavydrinking.?46?AppointeddeputycourtorganisttoChristianGottlobNeefeatasurprisinglyearlyagein1782Beethovenalsoplayedtheharpsichordandtheviola.In1792hewassenttoViennabyhispatronCountFerdinandWaldsteintostudymusicunderHaydn.??Beethovenremainedunmarried.?47?Continuallyplaguedbyillhealthhedevelopedanearinfectionwhichledtohistragicdeafnessin1819.???48?Hecompletedmaturemasterpiecesofgreatmusicaldepth:threepianosonatasfourstringquartetstheMissaSolemnisandthe9thSymphony.Hediedin1827.?49???NotingthatBeethovenoftenflewintofitsofrageGoetheoncesaidofhimIamastonishedbyhistalentbutheisunfortunatelyanaltogetheruntamedpersonality.?50????A.Inspiteofthishandicaphoweverhecontinuedtowritemusic.???B.Becauseofirregularpaymentsfromhispublishersanderraticsupportfromhispatronshewastroubledbyfinancialworriesthroughouthisadultlife.???C.Hislifewasmarkedbyapassionatededicationtoindependence.??D.WhenhismotherdiedBeethoventhenayoungmanwasnamedguardianofhistwoyoungerbrothers.??E.AlthoughBeethoven’spersonalitymayhavebeenuntamedhismusicshowsgreatdisciplineandcontrolandthisishowwerememberhimbest.??F.Todayhismusicisstillbeingplayedallovertheworld.
SeeingtheWorldCenturiesAgo IfyouenjoylookingthroughtravelbooksbysuchfamiliarauthorsasArthurFormerorEugeneFodoritwillnotsurpriseyoutoleanthattravelwritinghasalongandvenerablehistory.Almostfromtheearliestannalsofrecordedtimeindividualshavefoundreadyaudiencesfortheiraccountsofjourneystostrangeandexoticlocales. OneoftheearliesttravelwritersaGreekgeographerandhistoriannamedStrabolivedaroundthetimeofChrist.ThoughStraboisknowntohavetraveledfromeastoftheBlackSeawesttoItalyandasfarsouthasEthiopiahealsouseddetailsgleanedfromotherwriterstoextendandenlivenhisaccounts.HismultivolumedworkGeographyprovidestheonlysurvivingaccountofthecitiespeoplescustomsandgeographicalpeculiaritiesofthewholeknownworldofhistime. TwootherclassictravelwriterstheItalianMarcoPoloandtheMoroccanIbnBattutahlivedinroughlythesametimeperiod.MarcoPolotraveledtoChinawithhisfatheranduncleinaboutA.D.1275andremainedthere16or17yearsvisitingseveralothercountriesduringhistravels.WhenMarcoreturnedtoItalyhedictatedhismemoirsincludingstorieshehadheardfromotherstoascribewiththeresultingbookThemillionbeinganinstantsuccess.ThoughdifficulttoattesttotheaccuracyofallhesaysMarco’sbookimpelledEuropeanstobegintheirgreatvoyagesofexploration. IbnBattutah’sinterestintravelbeganonhisrequiredMuslimjourneytoMeccain1325andduringhislifetimehejourneyedthroughallthecountrieswhereIslamheldsway.HistravelbooktheRihlahisapersonalizedaccountofdesertjourneyscourtintriguesandeventheeffectoftheBlackDeathinthevariouslandshevisited.Inalmost30yearsoftravelingitisestimatedthatIbnBattutahcoveredmorethan75000miles. IbnBattutahtraveled.
EatMoreWeighLessLiveLonger Clevergeneticdetectiveworkmayhavefoundoutthereasonwhyanear-starvationdietprolongsthelifeofmanyanimals. RonaldKahnatHarvardMedicalSchoolinBostonUSandhiscolleagueshavebeenabletoextendthelifespan寿命ofmiceby18percentbyblockingtherodent’s啮齿动物increaseoffatinspecificcells.Thissuggeststhatthinness—andnotnecessarilydiet—promoteslonglifein"calorie热量单位卡restricted"animals. "It’sverycoolwork"saysagingresearcherCynthiaKenyonoftheUniversityofCaliforniaSanFrancisco."Thesemiceeatalltheywantloseweightandlivelonger.It’slikeheaven." Calorierestrictiondramaticallyextendsthelifespanoforganismsasdifferentaswormsandrodents.Whetherthisworksinhumansisstillunknownpartlybecausefewpeoplearewillingtosubmittosuchastrictdiet. Butmanyresearchershopetheywillbeabletotriggerthesameeffectwithadrugoncetheyunderstandhowlessfoodleadstoalongerlife.Onetheoryisthateatinglessreducestheincreaseofharmfulthingsthatcandamagecells.ButKahn’steamwonderedwhethertheanimalssimplybenefitbybecomingthin. Tofindouttheyusedbiologytrickstodisrupttheinsulin胰岛素receptor受体geneinlabmice—butonlyintheirfatcells."Sinceinsulinisneededtohelpfatceilsstorefattheseanimalswereprotectedagainstbecomingfat"explainsKahn. Thisslightgeneticchangeinasingletissuehaddramaticeffects.BythreemonthsofageKahn’smodifiedmicehadupto70percentlessbodyfatthannormalcontrolmicedespitethefactthattheyate55percentmorefoodpergramofbodyweight. Inadditiontheirlifespanincreased.Theaveragecontrolmouselived753dayswhilethethinrodentsaveragedalifespanof887days.Afterthreeyearsallthecontrolmicehaddiedbutone-quarterofthemodifiedrodentswerestillalive. "Thattheygettheseeffectsbyjustmanipulatingthefatcellsiscontroversial"saysLeonardGuarenteoftheMassachusettsInstituteofTechnologywhostudiescalorierestrictionandaging. ButGuarentesaysKahnhasyettoprovethatthesameeffectisresponsibleforincreasedlifespanincalorie-restrictedanimals."Itmightbethesameeffectortheremightbetworoutestolonglife"hepointsout"andthatwouldbeveryinteresting./ Theaveragemodifiedmouselived.
EatMoreWeighLessLiveLonger Clevergeneticdetectiveworkmayhavefoundoutthereasonwhyanear-starvationdietprolongsthelifeofmanyanimals. RonaldKahnatHarvardMedicalSchoolinBostonUSandhiscolleagueshavebeenabletoextendthelifespan寿命ofmiceby18percentbyblockingtherodent’s啮齿动物increaseoffatinspecificcells.Thissuggeststhatthinness—andnotnecessarilydiet—promoteslonglifein"calorie热量单位卡restricted"animals. "It’sverycoolwork"saysagingresearcherCynthiaKenyonoftheUniversityofCaliforniaSanFrancisco."Thesemiceeatalltheywantloseweightandlivelonger.It’slikeheaven." Calorierestrictiondramaticallyextendsthelifespanoforganismsasdifferentaswormsandrodents.Whetherthisworksinhumansisstillunknownpartlybecausefewpeoplearewillingtosubmittosuchastrictdiet. Butmanyresearchershopetheywillbeabletotriggerthesameeffectwithadrugoncetheyunderstandhowlessfoodleadstoalongerlife.Onetheoryisthateatinglessreducestheincreaseofharmfulthingsthatcandamagecells.ButKahn’steamwonderedwhethertheanimalssimplybenefitbybecomingthin. Tofindouttheyusedbiologytrickstodisrupttheinsulin胰岛素receptor受体geneinlabmice—butonlyintheirfatcells."Sinceinsulinisneededtohelpfatceilsstorefattheseanimalswereprotectedagainstbecomingfat"explainsKahn. Thisslightgeneticchangeinasingletissuehaddramaticeffects.BythreemonthsofageKahn’smodifiedmicehadupto70percentlessbodyfatthannormalcontrolmicedespitethefactthattheyate55percentmorefoodpergramofbodyweight. Inadditiontheirlifespanincreased.Theaveragecontrolmouselived753dayswhilethethinrodentsaveragedalifespanof887days.Afterthreeyearsallthecontrolmicehaddiedbutone-quarterofthemodifiedrodentswerestillalive. "Thattheygettheseeffectsbyjustmanipulatingthefatcellsiscontroversial"saysLeonardGuarenteoftheMassachusettsInstituteofTechnologywhostudiescalorierestrictionandaging. ButGuarentesaysKahnhasyettoprovethatthesameeffectisresponsibleforincreasedlifespanincalorie-restrictedanimals."Itmightbethesameeffectortheremightbetworoutestolonglife"hepointsout"andthatwouldbeveryinteresting./ Accordingtothepassagewedonotknowwhetherhumanswillbenefitfromtakinginfewercaloriespartlybecause.
Animals’"SixthSense" AtsunamiwastriggeredbyanearthquakeintheIndianOceaninDecember2004.ItkilledtensofthousandsofpeopleinAsiaandEastAfrica.Wildanimals51seemtohaveescapedthatterribletsunami.Thisphenomenonaddsweighttonotionsthattheypossessa"sixthsense"for52expertssaid. SriLankanwildlifeofficialshavesaidthegiantwavesthatkilledover24000peoplealongtheIndianOceanisland’scoastclearly53wildbeastswithnodeadanimalsfound. "Noelephantsaredeadnot54adeadrabbit.Ithinkanimalscan55disaster.Theyhaveasixthsense.Theyknowwhenthingsarehappening"H.D.RatnayakedeputydirectorofSriLanka’sWildlifeDepartmentsaidaboutonemonthafterthetsunamiattack.The56washedfloodwatersupto2milesinlandatYalaNationalParkintheravagedsoutheastSriLanka’sbiggestwildlife57andhometohundredsofwildelephantsandseveralleopards. "Therehasbeenalotof58evidenceaboutdogsbarkingorbirdsmigratingbeforevolcaniceruptionsorearthquakes.Butithasnotbeenproven"saidMatthewvanLieropananimalbehavior59atJohannesburgZoo. "Therehavebeenno60studiesbecauseyoucan’treallytestitinalaborfieldsetting"hetoldReuters.Otherauthoritiesconcurredwiththis61. "Wildlifeseemtobeabletopickupcertain62especiallybirds...therearemanyreportsofbirdsdetectingimpendingdisasters"saidCliveWalkerwhohaswrittenseveralbooksonAfricanwildlife.Animals63relyontheknownsensessuchassmellorhearingtoavoiddangersuchaspredators. Thenotionofananimal"sixthsense"—or64othermythicalpowerisanenduringonewhichtheevidenceonSriLanka’sravagedcoastislikelytoaddto. TheRomanssawowls65omensofimpendingdisasterandmanyancientculturesviewedelephantsassacredanimalsendowedwithspecialpowerorattributes. 62
Itwashardtosaywhythemandeservedsuchshabbytreatment.
Animals’"SixthSense" AtsunamiwastriggeredbyanearthquakeintheIndianOceaninDecember2004.ItkilledtensofthousandsofpeopleinAsiaandEastAfrica.Wildanimals51seemtohaveescapedthatterribletsunami.Thisphenomenonaddsweighttonotionsthattheypossessa"sixthsense"for52expertssaid. SriLankanwildlifeofficialshavesaidthegiantwavesthatkilledover24000peoplealongtheIndianOceanisland’scoastclearly53wildbeastswithnodeadanimalsfound. "Noelephantsaredeadnot54adeadrabbit.Ithinkanimalscan55disaster.Theyhaveasixthsense.Theyknowwhenthingsarehappening"H.D.RatnayakedeputydirectorofSriLanka’sWildlifeDepartmentsaidaboutonemonthafterthetsunamiattack.The56washedfloodwatersupto2milesinlandatYalaNationalParkintheravagedsoutheastSriLanka’sbiggestwildlife57andhometohundredsofwildelephantsandseveralleopards. "Therehasbeenalotof58evidenceaboutdogsbarkingorbirdsmigratingbeforevolcaniceruptionsorearthquakes.Butithasnotbeenproven"saidMatthewvanLieropananimalbehavior59atJohannesburgZoo. "Therehavebeenno60studiesbecauseyoucan’treallytestitinalaborfieldsetting"hetoldReuters.Otherauthoritiesconcurredwiththis61. "Wildlifeseemtobeabletopickupcertain62especiallybirds...therearemanyreportsofbirdsdetectingimpendingdisasters"saidCliveWalkerwhohaswrittenseveralbooksonAfricanwildlife.Animals63relyontheknownsensessuchassmellorhearingtoavoiddangersuchaspredators. Thenotionofananimal"sixthsense"—or64othermythicalpowerisanenduringonewhichtheevidenceonSriLanka’sravagedcoastislikelytoaddto. TheRomanssawowls65omensofimpendingdisasterandmanyancientculturesviewedelephantsassacredanimalsendowedwithspecialpowerorattributes. 54
{{*HTML*}}LudwigVanBeethoven??LudwigvanBeethovenamajorcomposerofthenineteenthcenturyovercamemanypersonalproblemstoachieveartisticgreatness.??BorninBonnGermanyin1770hefirststudiedmusicwiththecourtorganistGillesvanderEeden.Hisfatherwasexcessivelystrictandgiventoheavydrinking.?46?AppointeddeputycourtorganisttoChristianGottlobNeefeatasurprisinglyearlyagein1782Beethovenalsoplayedtheharpsichordandtheviola.In1792hewassenttoViennabyhispatronCountFerdinandWaldsteintostudymusicunderHaydn.??Beethovenremainedunmarried.?47?Continuallyplaguedbyillhealthhedevelopedanearinfectionwhichledtohistragicdeafnessin1819.???48?Hecompletedmaturemasterpiecesofgreatmusicaldepth:threepianosonatasfourstringquartetstheMissaSolemnisandthe9thSymphony.Hediedin1827.?49???NotingthatBeethovenoftenflewintofitsofrageGoetheoncesaidofhimIamastonishedbyhistalentbutheisunfortunatelyanaltogetheruntamedpersonality.?50????A.Inspiteofthishandicaphoweverhecontinuedtowritemusic.???B.Becauseofirregularpaymentsfromhispublishersanderraticsupportfromhispatronshewastroubledbyfinancialworriesthroughouthisadultlife.???C.Hislifewasmarkedbyapassionatededicationtoindependence.??D.WhenhismotherdiedBeethoventhenayoungmanwasnamedguardianofhistwoyoungerbrothers.??E.AlthoughBeethoven’spersonalitymayhavebeenuntamedhismusicshowsgreatdisciplineandcontrolandthisishowwerememberhimbest.??F.Todayhismusicisstillbeingplayedallovertheworld.
TheCherokeeNation LongbeforethewhitemancametoAmericathelandbelongedtotheAmericanIndiannations.ThenationoftheCherokeeslivedinwhatisnowthesoutheasternpartoftheUnitedStates. AfterthewhitemancametheCherokeescopiedmanyoftheirways.OneCherokeenamedSequoyahsawhowimportantreadingandwritingwastothewhiteman.HedecidedtoinventawaytowritedownthespokenCherokeelanguage.Hebeganbymakingwordpictures.Foreachwordhedrewapicture.Butthatprovedimpossible—therewerejusttoomanywords.Thenhetookthe85soundsthatmadeupthelanguage.UsinghisownimaginationandanEnglishspellingbookSequoyahinventedasignforeachsound.Hisalphabetprovedamazinglyeasytolearn.BeforelongmanyCherokeesknewhowtoreadandwriteintheirownlanguage.By1828theywereevenprintingtheirownnewspaper. In1830theUSCongresspassedalaw.ItallowedthegovernmenttoremoveIndiansfromtheirlands.TheCherokeesrefusedtogo.Theyhadlivedontheirlandsforcenturies.Itbelongedtothem.WhyshouldtheygotoastrangelandfarbeyondtheMississippiRiver ThearmywassenttodrivetheCherokeesout.Soldierssurroundedtheirvillagesandmarchedthematgunpointintothewesternterritory.Thesicktheoldandthesmallchildrenwentincartsalongwiththeirbelongings.Therestofthepeoplemarchedonfootorrodeonhorseback.ItwasNovemberyetmanyofthemstillworetheirsummerclothes.ColdandhungrytheCherokeeswerequicklyexhaustedbythehardshipsofthejourney.Manydroppeddeadandwereburiedbytheroadside.WhenthelastgrouparrivedintheirnewhomeinMarch1839morethan4000haddied.Itwasindeedamarchofdeath. TheCherokeeNationusedtolive.
TheCherokeeNation LongbeforethewhitemancametoAmericathelandbelongedtotheAmericanIndiannations.ThenationoftheCherokeeslivedinwhatisnowthesoutheasternpartoftheUnitedStates. AfterthewhitemancametheCherokeescopiedmanyoftheirways.OneCherokeenamedSequoyahsawhowimportantreadingandwritingwastothewhiteman.HedecidedtoinventawaytowritedownthespokenCherokeelanguage.Hebeganbymakingwordpictures.Foreachwordhedrewapicture.Butthatprovedimpossible—therewerejusttoomanywords.Thenhetookthe85soundsthatmadeupthelanguage.UsinghisownimaginationandanEnglishspellingbookSequoyahinventedasignforeachsound.Hisalphabetprovedamazinglyeasytolearn.BeforelongmanyCherokeesknewhowtoreadandwriteintheirownlanguage.By1828theywereevenprintingtheirownnewspaper. In1830theUSCongresspassedalaw.ItallowedthegovernmenttoremoveIndiansfromtheirlands.TheCherokeesrefusedtogo.Theyhadlivedontheirlandsforcenturies.Itbelongedtothem.WhyshouldtheygotoastrangelandfarbeyondtheMississippiRiver ThearmywassenttodrivetheCherokeesout.Soldierssurroundedtheirvillagesandmarchedthematgunpointintothewesternterritory.Thesicktheoldandthesmallchildrenwentincartsalongwiththeirbelongings.Therestofthepeoplemarchedonfootorrodeonhorseback.ItwasNovemberyetmanyofthemstillworetheirsummerclothes.ColdandhungrytheCherokeeswerequicklyexhaustedbythehardshipsofthejourney.Manydroppeddeadandwereburiedbytheroadside.WhenthelastgrouparrivedintheirnewhomeinMarch1839morethan4000haddied.Itwasindeedamarchofdeath. Alawwaspassedin1830to.
Animals’"SixthSense" AtsunamiwastriggeredbyanearthquakeintheIndianOceaninDecember2004.ItkilledtensofthousandsofpeopleinAsiaandEastAfrica.Wildanimals51seemtohaveescapedthatterribletsunami.Thisphenomenonaddsweighttonotionsthattheypossessa"sixthsense"for52expertssaid. SriLankanwildlifeofficialshavesaidthegiantwavesthatkilledover24000peoplealongtheIndianOceanisland’scoastclearly53wildbeastswithnodeadanimalsfound. "Noelephantsaredeadnot54adeadrabbit.Ithinkanimalscan55disaster.Theyhaveasixthsense.Theyknowwhenthingsarehappening"H.D.RatnayakedeputydirectorofSriLanka’sWildlifeDepartmentsaidaboutonemonthafterthetsunamiattack.The56washedfloodwatersupto2milesinlandatYalaNationalParkintheravagedsoutheastSriLanka’sbiggestwildlife57andhometohundredsofwildelephantsandseveralleopards. "Therehasbeenalotof58evidenceaboutdogsbarkingorbirdsmigratingbeforevolcaniceruptionsorearthquakes.Butithasnotbeenproven"saidMatthewvanLieropananimalbehavior59atJohannesburgZoo. "Therehavebeenno60studiesbecauseyoucan’treallytestitinalaborfieldsetting"hetoldReuters.Otherauthoritiesconcurredwiththis61. "Wildlifeseemtobeabletopickupcertain62especiallybirds...therearemanyreportsofbirdsdetectingimpendingdisasters"saidCliveWalkerwhohaswrittenseveralbooksonAfricanwildlife.Animals63relyontheknownsensessuchassmellorhearingtoavoiddangersuchaspredators. Thenotionofananimal"sixthsense"—or64othermythicalpowerisanenduringonewhichtheevidenceonSriLanka’sravagedcoastislikelytoaddto. TheRomanssawowls65omensofimpendingdisasterandmanyancientculturesviewedelephantsassacredanimalsendowedwithspecialpowerorattributes. 64
Wemustabidebytherules.
ComputerMouse Thebasiccomputermouseisanamazinglycleverinventionwitharelativelysimpledesignthatallowsustopointatthingsonthecomputeranditisveryproductive.Thinkofallthethingsyoucandowithamouselikeselectingtextforcopyingandpastingdrawingandevenscrollingonthepagewiththenewermicewiththewheel.Mostofususethecomputermousedailywithoutstoppingtothinkhowitworksuntilitgetsdirtyandwehavetolearnhowtocleanit.Welearntopointatthingsbeforewelearntospeaksothemouseisaverynaturalpointingdevice.Othercomputerpointingdevicesincludelightpensgraphicstabletsandtouchscreensbutthemouseisstillourworkhorse. Thecomputermousewasinventedin1964byDouglasEnglehartofStanfordUniversity.Ascomputerscreensbecamemorepopularandarrowkeyswereusedtomovearoundabodyoftextitbecameclearthatapointingdevicethatallowedeasiermotionthroughthetextandevenselectionoftextwouldbeveryuseful.TheintroductionofthemousewiththeAppleLisacomputerin1983reallystartedthecomputerpublicontheroadtorelyingonthemouseforroutinecomputertasks. HowdoesthemouseworkWehavetostartatthebottomsothinkupsidedownfornow.Itallstartswiththemouseball.Asthemouseballinthebottomofthemouserollsoverthemousepaditpressesagainstandturnstwoshafts.Theshaftsareconnectedtowheelswithseveralsmallholesinthem.Thewheelshaveapairofsmallelectroniclight-emittingdevicescalledlight-emittingdiodesLEDmountedoneitherside.OneLEDsendsalightbeamtotheLEDontheotherside.AsthewheelsspinandaholerotatesbythelightbeamgetsthroughtotheLEDontheotherside.Butamomentlaterthelightbeamisblockeduntilthenextholeisinplace.TheLEDdetectsachangingpatternoflightconvertsthepatternintoanelectronicsignalandsendsthesignaltothecomputerthroughwiresinacablethatgoesoutofthemousebody.Thiscableisthetailthathelpsgivethemouseitsname.Thecomputerinterpretsthesignaltotellitwheretopositionthecursoronthecomputerscreen. Sofarwehaveonlydiscussedthebasiccomputermousethatmostofyouprobablyhaveorhaveused.Oneproblemwiththisdesignisthatthemousegetsdirtyastheballrollsoverthesurfaceandpicksupdirt.Eventuallyyouhavetocleanyourmouse.Theneweropticalmiceavoidthisproblembyhavingnomovingparts. Mostcomputeruserswanttoknowhowthecomputermouseworks.
Theoncebarrenhillsidesarenowgoodfarmland.
ComputerMouse Thebasiccomputermouseisanamazinglycleverinventionwitharelativelysimpledesignthatallowsustopointatthingsonthecomputeranditisveryproductive.Thinkofallthethingsyoucandowithamouselikeselectingtextforcopyingandpastingdrawingandevenscrollingonthepagewiththenewermicewiththewheel.Mostofususethecomputermousedailywithoutstoppingtothinkhowitworksuntilitgetsdirtyandwehavetolearnhowtocleanit.Welearntopointatthingsbeforewelearntospeaksothemouseisaverynaturalpointingdevice.Othercomputerpointingdevicesincludelightpensgraphicstabletsandtouchscreensbutthemouseisstillourworkhorse. Thecomputermousewasinventedin1964byDouglasEnglehartofStanfordUniversity.Ascomputerscreensbecamemorepopularandarrowkeyswereusedtomovearoundabodyoftextitbecameclearthatapointingdevicethatallowedeasiermotionthroughthetextandevenselectionoftextwouldbeveryuseful.TheintroductionofthemousewiththeAppleLisacomputerin1983reallystartedthecomputerpublicontheroadtorelyingonthemouseforroutinecomputertasks. HowdoesthemouseworkWehavetostartatthebottomsothinkupsidedownfornow.Itallstartswiththemouseball.Asthemouseballinthebottomofthemouserollsoverthemousepaditpressesagainstandturnstwoshafts.Theshaftsareconnectedtowheelswithseveralsmallholesinthem.Thewheelshaveapairofsmallelectroniclight-emittingdevicescalledlight-emittingdiodesLEDmountedoneitherside.OneLEDsendsalightbeamtotheLEDontheotherside.AsthewheelsspinandaholerotatesbythelightbeamgetsthroughtotheLEDontheotherside.Butamomentlaterthelightbeamisblockeduntilthenextholeisinplace.TheLEDdetectsachangingpatternoflightconvertsthepatternintoanelectronicsignalandsendsthesignaltothecomputerthroughwiresinacablethatgoesoutofthemousebody.Thiscableisthetailthathelpsgivethemouseitsname.Thecomputerinterpretsthesignaltotellitwheretopositionthecursoronthecomputerscreen. Sofarwehaveonlydiscussedthebasiccomputermousethatmostofyouprobablyhaveorhaveused.Oneproblemwiththisdesignisthatthemousegetsdirtyastheballrollsoverthesurfaceandpicksupdirt.Eventuallyyouhavetocleanyourmouse.Theneweropticalmiceavoidthisproblembyhavingnomovingparts. Theopticalmouseissuperiortothebasiconeinthattheformerhasnomovingparts.
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