ites ▁and ▁his ▁attempts ▁to ▁build ▁a ▁k ite ▁that ▁was ▁scal able ▁and ▁big ▁enough ▁to ▁carry ▁both ▁a ▁man ▁and ▁a ▁motor . ▁As ▁such , ▁it ▁was ▁an ▁early ▁experiment ▁on ▁the ▁road ▁to ▁man ned ▁flight . ▁He ▁worked ▁on ▁the ▁k ites ▁between ▁ 1 8 9 5 ▁and ▁ 1 9 1 0 . ▁Bell ▁wrote ▁about ▁his ▁discovery ▁of ▁this ▁concept ▁in ▁the ▁June ▁ 1 9 0 3 ▁issue ▁of ▁National ▁Geographic ▁magazine ; ▁the ▁article ▁was ▁titled ▁" T etra hed ral ▁Princi ple ▁in ▁K ite ▁Str ucture ". ▁ ▁From ▁an ▁initial ▁one - cell ▁model , ▁Bell ▁advanced ▁to ▁a ▁ 3 , 3 9 3 - cell ▁" C yg net " ▁model ▁in ▁ 1 9 0 7 . ▁This ▁ 4 0 - foot - long ▁( 1 2 . 2 ▁m ), ▁ 2 0 0 - p ound ▁( 9 1 ▁kil ogram ) ▁k ite ▁was ▁to wed ▁by ▁a ▁ste amer ▁off sh ore ▁near ▁Bad deck , ▁Nova ▁Scot ia , ▁on ▁December ▁ 6 , ▁ 1 9 0 7 , ▁and ▁carried ▁a ▁man ▁ 1 6 8 ▁feet ▁( 5 1 . 2 ▁metres ) ▁above ▁the ▁water . ▁ ▁Bell ▁also ▁experiment ed ▁with ▁a ▁large ▁circular ▁" t etra hed ral ▁tr uss " ▁design ▁during ▁the ▁same ▁period . ▁ ▁The ▁t etra hed ral ▁k ite ▁is ▁stable ▁and ▁easy ▁to ▁fly , ▁but ▁is ▁not