ically ▁delivered ▁t anks ▁of ▁the ▁fl amm able ▁gas ▁ac et yl ene . ▁A ▁reliable ▁pilot ▁light ▁burn ed ▁day ▁and ▁night . ▁When ▁the ▁sun ▁set , ▁the ▁resulting ▁drop ▁in ▁temperature ▁would ▁open ▁a ▁precision ▁val ve ▁and ▁release ▁a ▁flow ▁of ▁ac et yl ene ▁against ▁the ▁pilot ▁light , ▁causing ▁the ▁light ▁to ▁sh ine . ▁ ▁When ▁last ▁L ighth ouse ▁ke eper ▁left ▁in ▁ 1 9 2 9 , ▁it ▁quickly ▁de grad ed . ▁ ▁" The ▁light ▁earned ▁the ▁nick name ▁' The ▁D ummy ' ” ▁from ▁the ▁loc als ." ▁ ▁In ▁the ▁second ▁half ▁of ▁the ▁ 2 0 th ▁century , ▁the ▁in vention ▁of ▁rad ar ▁and ▁other ▁electronic ▁a ids ▁to ▁navigation ▁began ▁to ▁render ▁many ▁Great ▁L akes ▁navig ational ▁light ▁to wers ▁redundant . ▁The ▁C rib ▁Light ▁was ▁considered ▁by ▁the ▁Coast ▁Guard ▁to ▁be ▁" sur plus " ▁property . ▁In ▁ 1 9 8 4 , ▁the ▁C rib ▁Light ▁tower ▁was ▁removed ▁from ▁its ▁c rib ▁and ▁placed ▁on ▁its ▁current ▁base ▁located ▁on ▁the ▁Gordon ▁Turner ▁Park ▁pier ▁head . ▁ ▁As ▁noted ▁by ▁a ▁Coast ▁Guard ▁research er : ▁The ▁light ▁earned ▁the ▁nick name ▁“ The ▁D ummy ” ▁from ▁the ▁loc als . ▁When ▁loc als ▁learned ▁of ▁the ▁Coast ▁Guard ’ s ▁plans ▁to ▁demol ish ▁the ▁site , ▁an ▁agreement ▁was ▁made ▁to ▁don ate ▁the ▁light ▁to ▁the ▁city ▁of ▁Che bo yg