▁with ▁the ▁Canadian ▁National ▁Research ▁Council ▁as ▁part ▁of ▁the ▁war ▁effort . ▁He ▁was ▁the ▁co - in vent or ▁of ▁the ▁ ▁sl otted ▁wave guide ▁anten na . ▁The ▁anten nas ▁were ▁first ▁used ▁for ▁the ▁air ▁defense ▁of ▁Great ▁Britain . ▁After ▁the ▁war ▁the ▁technology ▁was ▁adapted ▁for ▁use ▁in ▁ocean - going ▁vessels , ▁including ▁small ▁fish ing ▁boats . ▁It ▁was ▁also ▁used ▁in ▁N OR AD ' s ▁P inet ree ▁Line , ▁a ▁series ▁of ▁rad ar ▁stations ▁built ▁in ▁Canada ▁and ▁the ▁United ▁States ▁in ▁the ▁ 1 9 5 0 s ▁for ▁the ▁purpose ▁of ▁detect ing ▁Soviet ▁bom bers ▁approaching ▁North ▁America . ▁Gu pt ill ▁and ▁co - in vent or ▁W . H . ▁Watson ▁were ▁granted ▁a ▁United ▁States ▁pat ent ▁for ▁the ▁device , ▁described ▁as ▁a ▁" direct ive ▁anten na ▁for ▁mic row aves ", ▁in ▁ 1 9 5 1 . ▁ ▁Career ▁at ▁Dal h ous ie ▁University ▁ ▁Gu pt ill ▁began ▁teaching ▁ ▁at ▁Dal h ous ie ▁University ▁in ▁ 1 9 4 7 . ▁After ▁a ▁s abb at ical ▁year ▁at ▁the ▁University ▁of ▁Le iden ▁he ▁was ▁named ▁head ▁of ▁Dal h ous ie ' s ▁physics ▁department , ▁a ▁position ▁he ▁held ▁for ▁ten ▁years ▁before ▁returning ▁to ▁teaching ▁and ▁research ▁full - time . ▁He ▁was ▁described ▁as ▁" that ▁tre asure , ▁an ▁excellent ▁research er ▁and ▁a ▁gift ed ▁teacher ". ▁Among ▁his