Oceanographyhasbeendefinedas“Theapplicationofallsciencestothestudyofthesea”.Beforethenineteenthcenturyscientistswithaninterestintheseawerefew.
Formostpeopletheseawasremoteandwiththeexceptionofearlyintercontinentaltravelersorotherswhoearnedalivingfromtheseatherewaslittlereasontoaskmanyquestionsaboutitletalonetoaskwhatlaybeneaththesurface.Thefirsttimethatthequestion'Whatisatthebottomoftheoceans?'hadtobeansweredwithanycommercialconsequencewaswhenthelayingofatelegraphcablefromEuropetoAmericawasproposed.Theengineershadtoknowthedepthprofile(起伏形状)oftheroutetoestimatethelengthofcablethathadtobemanufactured.
ItwastoMauryoftheUSNavythattheAtlanticTelegraphCompanyturnedin1853forinformationonthismatter.Inthe1840sMauryhadbeenresponsibleforencouragingvoyagesduringwhichsoundings(测深)weretakentoinvestigatethedepthsoftheNorthAtlanticandPacificOceans.LatersomeofhisfindingsarousedmuchpopularinterestinhisbookThePhysicalGeographyoftheSea.
Thecablewaslaidbutnotuntil1866wastheconnectionmadepermanentandreliable.Attheearlyattemptsthecablefailedandwhenitwastakenoutforrepairsitwasfoundtobecoveredinlivinggrowthsafactwhichdefiedcontemporaryscientificopinionthattherewasnolifeinthedeeperpartsofthesea.
Withinafewyearsoceanographywasunderway.In1872Thomsonledascientificexpeditionwhichlastedforfouryearsandbroughthomethousandsofsamplesfromthesea.Theirclassificationandanalysisoccupiedscientistsforyearsandledtoafive-volumereportthelastvolumebeingpublishedin1895.
68.Thepassageimpliesthatthetelegraphcablewasbuiltmainly_________.
A)foroceanographicstudies
B)formilitarypurposes
C)forbusinessconsiderations
D)forinvestigatingthedepthsoftheoceans
69.TheaimofvoyagesMauryencouragedinthe1840swas__________.
A)tomakesomesoundexperimentsintheoceans
B)tocollectsamplesofseaplantsandanimals
C)toestimatethelengthofcablethatwastobemade
D)tomeasurethedepthsoftwooceans
70.'Defie