marine ▁rescue ▁chamber ▁in ▁ 1 9 3 0 . ▁Before ▁he ▁could ▁make ▁these ▁changes , ▁M oms en ▁went ▁to ▁the ▁Bureau ▁of ▁Const ruction ▁and ▁Rep air ▁to ▁work ▁on ▁an ▁under water ▁breath ing ▁appar atus ▁for ▁individual ▁esc apes . ▁M oms en ▁turned ▁to ▁de vis ing ▁the ▁" M oms en ▁L ung ", ▁demonstr ating ▁it ▁successfully ▁in ▁a ▁series ▁of ▁una ut hor ized ▁experiments ▁in ▁the ▁An ac ost ia ▁and ▁Pot om ac ▁R ivers , ▁and ▁finally ▁attract ed ▁enough ▁favor able ▁attention ▁to ▁see ▁the ▁lung ▁adopted ▁by ▁the ▁Navy ▁in ▁ 1 9 2 9 . ▁ ▁Lieutenant ▁Commander ▁All an ▁Rock well ▁McC ann ▁was ▁put ▁in ▁charge ▁of ▁the ▁revis ions ▁on ▁the ▁div ing ▁bell . ▁From ▁July ▁ 1 9 2 9 ▁to ▁July ▁ 1 9 3 1 , ▁McC ann ▁was ▁assigned ▁to ▁the ▁Main ten ance ▁Division , ▁Bureau ▁of ▁Const ruction ▁and ▁Rep air , ▁where ▁he ▁developed ▁the ▁sub marine ▁rescue ▁chamber . ▁When ▁the ▁bell ▁was ▁completed ▁in ▁late ▁ 1 9 3 0 , ▁it ▁was ▁produced ▁as ▁the ▁McC ann ▁Sub marine ▁Res cue ▁Chamber ▁( S RC ) ▁( N avy ▁designated ▁ ▁the ▁first ▁ 1 2 ▁of ▁these ▁as ▁[ Y RC ] ▁ 1 – 1 2 , ▁Y RC - 4 ▁was ▁lost ▁ab o ard ▁the ▁USS ▁P ige on , ▁at ▁B ata an , ▁Philippines , ▁during ▁the ▁first