▁construction ▁at ▁Dead man ▁Island ▁Lock ▁and ▁Dam ▁( now ▁called ▁the ▁D ash ield s ▁Lock ▁and ▁Dam ) ▁on ▁the ▁Ohio ▁River . ▁ ▁In ▁September ▁ 1 9 2 9 ▁Case y ▁was ▁assigned ▁to ▁the ▁R ivers ▁and ▁Har b ors ▁Section ▁of ▁the ▁Office ▁of ▁the ▁Chief ▁of ▁Engine ers ▁in ▁Washington , ▁DC . ▁This ▁job ▁involved ▁review ing ▁the ▁project ▁studies , ▁plans ▁and ▁specific ations ▁of ▁all ▁river ▁and ▁har bor ▁projects ▁throughout ▁the ▁United ▁States , ▁including ▁flo od ▁control ▁and ▁hydro elect ric ▁power ▁projects . ▁He ▁also ▁had ▁responsibility ▁for ▁correspond ence ▁with ▁U . S . ▁sen ators ▁and ▁con gress men . ▁During ▁this ▁time ▁he ▁co - des igned ▁and ▁pat ented ▁the ▁King man - Case y ▁Flo ating ▁Mo oring ▁Bit ▁for ▁navigation ▁lo cks . ▁He ▁was ▁promoted ▁to ▁the ▁substant ive ▁rank ▁of ▁captain ▁on ▁ 1 ▁May ▁ 1 9 3 3 . ▁ ▁Case y ▁won ▁a ▁John ▁R . ▁Fre eman ▁fellow ship ▁from ▁the ▁American ▁Society ▁of ▁Mechan ical ▁Engine ers ▁in ▁ 1 9 3 3 ▁to ▁study ▁hyd ra ul ics ▁and ▁civil ▁engineering ▁in ▁Germany . ▁For ▁the ▁next ▁two ▁years , ▁he ▁attended ▁the ▁Techn ische ▁Hoch schule ▁in ▁Berlin , ▁ear ning ▁a ▁Doctor ate ▁in ▁Engineering . ▁His ▁th esis , ▁written ▁in ▁German , ▁was ▁on ▁Gesch ieb ▁Bew egung , ▁the ▁bed load ▁movement ▁in ▁streams . ▁Return ing ▁to ▁the ▁United ▁States