ed ▁his ▁g arrison ▁of ▁some ▁ 7 0 0 ▁soldiers ▁there , ▁and ▁proceeded ▁to ▁pl under ▁most ▁of ▁the ▁surrounding ▁towns ▁and ▁villages . ▁ ▁After ▁the ▁island ▁was ▁acquired ▁by ▁Gust ave ▁le ▁Gu ill ou ▁de ▁Pen an ros ▁in ▁ 1 8 5 4 , ▁in ▁the ▁southern ▁part ▁of ▁the ▁island , ▁La ▁Plan iche ▁built ▁a ▁s ard ine ▁press . ▁Le ▁Gu ill ou ▁de ▁Pen an ros ▁developed ▁the ▁har bour ▁and ▁the ▁s ard ine ▁processing ▁plant ▁on ▁the ▁island , ▁the ▁first ▁of ▁its ▁kind . ▁The ▁s ard ine ▁industry ▁developed ▁as ▁Dou arn enez ' ▁principal ▁economic ▁activity ▁in ▁the ▁late ▁ 1 9 th ▁and ▁early ▁ 2 0 th ▁centuries . ▁In ▁ 1 9 1 1 , ▁the ▁island ▁was ▁purchased ▁by ▁Jean ▁R iche pin , ▁an ▁author ▁and ▁play w right . ▁He ▁built ▁the ▁rot unda ▁and ▁the ▁Chap elle ▁des ▁A vi ateurs ▁comm emor ating ▁the ▁first ▁trans at l antic ▁flight ▁from ▁Europe ▁to ▁the ▁United ▁States ▁by ▁Die ud onn é ▁Cost es ▁and ▁Maurice ▁Bell onte ▁in ▁September ▁ 1 9 3 0 . ▁ ▁In ▁ 1 9 9 5 , ▁the ▁island ▁was ▁bought ▁by ▁Conserv atoire ▁du ▁L itt oral . ▁It ▁has ▁carried ▁out ▁rest oration ▁work ▁on ▁the ▁buildings ▁and ▁maintained ▁the ▁paths ▁and ▁gard ens . ▁The ▁island ▁is ▁now ▁maintained ▁as ▁part ▁of ▁the ▁national ▁Par c ▁nature l ▁mar in ▁d