▁Europe , ▁Asia ▁and ▁Africa , ▁he ▁repe ats ▁Er at ost hen es ; ▁like ▁all ▁classical ▁ge ograph ers ▁from ▁Alexander ▁the ▁Great ▁( except ▁P to le my ) ▁he ▁regards ▁the ▁C asp ian ▁Sea ▁as ▁an ▁in let ▁of ▁the ▁Northern ▁Ocean , ▁corresponding ▁to ▁the ▁Pers ian ▁G ulf ▁and ▁the ▁Red ▁Sea ▁on ▁the ▁south . ▁ ▁Mar inus ▁of ▁Ty re ▁ ▁Mar inus ▁of ▁Ty re ▁was ▁a ▁H ellen ized ▁Pho en ician ▁ge ograph er ▁and ▁cart ograph er .< ref > “ Not es ▁on ▁An cient ▁Times ▁in ▁Mal aya ” ▁Roland ▁Br add ell . ▁Journal ▁of ▁the ▁Mal ay an ▁Branch ▁of ▁the ▁Royal ▁A si atic ▁Society , ▁Vol . ▁ 2 3 , ▁No . ▁ 3 ▁( 1 5 3 ) ▁ 1 9 4 7 ▁( 1 9 5 0 ), ▁p . ▁ 9 </ ref > ▁He ▁founded ▁mathematical ▁ge ography ▁and ▁provided ▁the ▁under p inn ings ▁of ▁P to le my ' s ▁influ ential ▁Ge ograph ia . ▁ ▁Mar inus ' s ▁ge ographical ▁treat ise ▁is ▁lost ▁and ▁known ▁only ▁from ▁P to le my ' s ▁remarks . ▁He ▁introduced ▁improvements ▁to ▁the ▁construction ▁of ▁maps ▁and ▁developed ▁a ▁system ▁of ▁na ut ical ▁charts . ▁His ▁chief ▁legacy ▁is ▁that ▁he ▁first ▁assigned ▁to ▁each ▁place ▁a ▁proper ▁latitude ▁and ▁longitude . ▁His ▁zero ▁mer id ian ▁ran ▁through ▁the ▁western most ▁land ▁known ▁to