▁to ▁the ▁a ft ▁tor ped o ▁room ▁h atch ▁on ▁May ▁ 2 5 . ▁This ▁run ▁confirmed ▁the ▁flo oding ▁of ▁the ▁entire ▁a ft ▁portion ▁of ▁the ▁ship . ▁ ▁Design ▁ ▁The ▁rescue ▁chamber ▁was ▁a ▁p ear ▁sh aped ▁steel ▁chamber , ▁the ▁big ▁end ▁upp erm ost , ▁seven ▁feet ▁at ▁the ▁greatest ▁diameter ▁and ▁ten ▁feet ▁high . ▁It ▁is ▁divided ▁into ▁an ▁upper ▁closed ▁compart ment ▁and ▁a ▁lower ▁open ▁compart ment ▁by ▁a ▁horizontal ▁bulk head ▁which ▁has ▁a ▁water ▁tight ▁h atch ▁in ▁its ▁middle . ▁S urr ounding ▁the ▁lower ▁compart ment ▁is ▁a ▁ball ast ▁tank ▁of ▁a ▁capacity ▁just ▁equal ▁to ▁that ▁of ▁the ▁lower ▁compart ment . ▁Inside ▁the ▁lower ▁compart ment ▁is ▁a ▁re el ▁with ▁ ▁of ▁ ▁steel ▁wire ▁on ▁it . ▁The ▁re el ▁is ▁operated ▁by ▁a ▁sh aft ▁leading ▁into ▁the ▁upper ▁compart ment . ▁The ▁sh aft ▁is ▁rot ated ▁by ▁an ▁air ▁motor . ▁On ▁the ▁bottom ▁edge ▁of ▁the ▁lower ▁compart ment ▁a ▁rub ber ▁g asket ▁is ▁embedded ▁into ▁a ▁circular ▁gro ove , ▁so ▁that ▁when ▁the ▁chamber ▁is ▁brought ▁into ▁contact ▁with ▁a ▁flat ▁surface ▁( the ▁h atch ▁ring ) ▁a ▁water ▁tight ▁joint ▁may ▁be ▁effect ed ▁with ▁the ▁application ▁of ▁pressure . ▁Att ached ▁to ▁the ▁upper ▁compart ment ▁is ▁an ▁air ▁supply ▁and ▁an ▁atmos pher ic ▁exhaust ▁h ose , ▁wire ▁w ound ▁for ▁strength . ▁Also ▁electric ▁c ables ▁for ▁tele