ABSTRACT
INTHEcouRsEofgeologicalinvestigationsintheregionof theDeadSeaduringthelastcentury,LouisLartet(sonofthe discovererofthefossilapeDryopithecus)founddepositswhichhe recognizedashavingbeenleftbythatlakewhenitswater stoodatamuchhigherlevelthanatpresent.In1865(Lartet, r865)hepublishedtheviewthattheformerexpansionofthe DeadSeacoincidedwiththeglacialperiod.Evidenceofraised lakelevelsinPleistocenetimeswaslaterfoundinmanyof thedrierpartsoftheworld,whilestudiesineasternCalifornia providedproofthattheriseoflakewatersinthatregionwas essentiallycontemporaneouswiththeadvanceofglaciersinthe neighbouringmountains(Russell,r887).Theseperiodsof higherlake-levelsbecameknownaspluvial 9 4 agesbecauseitwas inferredthattheyrepresentedtimesofincreasedrainfall.Since glaciersandice-sheetscanonlyformandgrowifthereisan increaseinprecipitation,itseemedreasonableenoughto correlatepluvialconditionsintropicalandsubtropicallowlandswithglacialconditionsinhigherlatitudesandmountains. In1914theEnglishmeteorologistC.E.P.Brooks(1914,rg26, p.315)formulatedthisgeneraltheoryofpluvial-glacialcorrelation,withitsimplicationthatinterglacialperiodsarc representedinthetropicsandsubtropicsbydryorinterpluvial 9 5 ages.IfpluvialphasesweresynchronicthroughoutAfrica,for example,andcontemporaneouswithglaciationsinEuropewe shouldhaveaninvaluablemeansofrelativedating,andfor thatreasonitisimportanttoexaminethetheoryofglacialpluvialcorrelationinsomedetail.Unfortunately,althougha greatdealoffactualdatahasbeencitedinsupportofit, recentresearches(Flint,1959)havethrownconsiderabledoubt
onthevalidityofmuchoftheevidencecountedasproofof climaticchangeinlowlatitudes.
