�������������������������������������������������������������������Cover,©MaryEvansPictureLibrary/TheImageWorks;page3,©LeonarddeSelva/CORBIS;page4,©GerardLacz/EarthScenes;page5,©MaryEvansPictureLibrary/TheImageWorks;page6,©ultonArchive/GettyImages;page7,©CORBIS;page8,©Bettmann/CORBIS;page9,©TimeLifePictures/Mansell/TimeLifePictures/GettyImages;page10,©Imagno/Getty;page11,©Rischgitz/GettyImages;page12,©FoxPhotos/GettyImages;page13,©Underwood&Underwood/CORBIS;page14,©Bettmann/CORBIS.Copyright©byHarcourt,Inc.Allrightsreserved.Nopartofthispublicationmaybereproducedortransmittedinanyformorbyanymeans,electronicormechanical,includingphotocopy,recording,oranyinformationstorageandretrievalsystem,withoutpermissioninwritingfromthepublisher.RequestsforpermissiontomakecopiesofanypartoftheworkshouldbeaddressedtoSchoolPer-missionsandCopyrights,Harcourt,Inc.,6277SeaHarborDrive,Orlando,Florida32887-6777.Fax:407-345-2418.HARCOURTandtheHarcourtLogoaretrademarksofHarcourt,Inc.,registeredintheUnitedStatesofAmericaand/orotherjurisdictions.PrintedintheUnitedStatesofAmericaISBN10:0-15-351685-2ISBN13:978-0-15-351685-6OrderingOptionsISBN10:0-15-351216-4(Grade6AdvancedCollection)ISBN13:978-0-15-351216-2(Grade6AdvancedCollection)ISBN10:0-15-358168-9(packageof5)ISBN13:978-0-15-358168-7(packageof5)Ifyouhavereceivedthesematerialsasexaminationcopiesfreeofcharge,HarcourtSchoolPub-lishersretainstitletothematerialsandtheymaynotberesold.Resaleofexaminationcopiesisstrictlyprohibitedandisillegal.Possessionofthispublicationinprintformatdoesnotentitleuserstoconvertthispublication,oranyportionofit,intoelectronicformat.1234567891017912111009080706byBarbaraA.DonovanOttoLilienthalAVIATIONPIONEER3TheLearningYearsIn1903,theWrightbrothersmadeanastoundingbreak-through.Theirswasthefirstpoweredandcontrolledhumanflight.Whentheirplaneflewonthathistoricday,theywerenotalone.Withthemwereallthepeoplewhohadtriedtoflybeforethem.Previousflig...