▁the ▁coordinate ▁system . ▁ ▁History ▁The ▁concept ▁of ▁" center ▁of ▁mass " ▁in ▁the ▁form ▁of ▁the ▁center ▁of ▁gravity ▁was ▁first ▁introduced ▁by ▁the ▁ ▁great ▁ancient ▁Greek ▁phys ic ist , ▁math ematic ian , ▁and ▁engineer ▁Arch im edes ▁of ▁Sy rac use . ▁He ▁worked ▁with ▁simplified ▁assumptions ▁about ▁gravity ▁that ▁amount ▁to ▁a ▁uniform ▁field , ▁thus ▁arriv ing ▁at ▁the ▁mathematical ▁properties ▁of ▁what ▁we ▁now ▁call ▁the ▁center ▁of ▁mass . ▁Arch im edes ▁showed ▁that ▁the ▁tor que ▁ex ert ed ▁on ▁a ▁lever ▁by ▁weights ▁rest ing ▁at ▁various ▁points ▁along ▁the ▁lever ▁is ▁the ▁same ▁as ▁what ▁it ▁would ▁be ▁if ▁all ▁of ▁the ▁weights ▁were ▁moved ▁to ▁a ▁single ▁point — the ir ▁center ▁of ▁mass . ▁In ▁work ▁on ▁floating ▁bodies ▁he ▁demonstrated ▁that ▁the ▁orientation ▁of ▁a ▁floating ▁object ▁is ▁the ▁one ▁that ▁makes ▁its ▁center ▁of ▁mass ▁as ▁low ▁as ▁possible . ▁He ▁developed ▁mathematical ▁techniques ▁for ▁finding ▁the ▁cent ers ▁of ▁mass ▁of ▁objects ▁of ▁uniform ▁density ▁of ▁various ▁well - defined ▁shapes . ▁ ▁Later ▁mathemat icians ▁who ▁developed ▁the ▁theory ▁of ▁the ▁center ▁of ▁mass ▁include ▁P app us ▁of ▁Alexand ria , ▁Gu ido ▁U b ald i , ▁Francesco ▁Mau ro lic o , ▁Feder ico ▁Command ino , ▁Simon ▁Ste vin , ▁Lu ca ▁Val er io , ▁Jean - Char les ▁de ▁la ▁F aille , ▁Paul ▁G uld in , ▁John ▁Wall is , ▁Louis ▁Car ré , ▁Pierre