▁by ▁sap on ification ; ▁it ▁may ▁be ▁sod ium ▁carbon ate ▁( ly e , ▁was hing ▁s oda , ▁). ▁▁ ▁The ▁d eter gent ▁is ▁usually ▁an ▁an ionic ▁sur fact ant . ▁ ▁Its ▁role ▁is ▁to ▁help ▁remove ▁gre asy ▁material ▁( such ▁as ▁gre ase ) ▁as ▁an ▁em ulsion , ▁and ▁to ▁keep ▁the ▁removed ▁st ain ▁particles ▁susp ended ▁in ▁the ▁ab ras ive ▁paste . ▁ ▁The ▁dry ▁ble ach ▁is ▁usually ▁a ▁product ▁that ▁releases ▁ch lor ine ▁( more ▁precisely ▁hy po ch lor ite , ▁the ▁classical ▁household ▁ble aching ▁agent ), ▁such ▁as ▁tr ich lor ois oc yan ur ic ▁acid . ▁ ▁The ▁Bar ▁Keep ers ▁Friend ▁sc our ing ▁pow der ▁has ▁ox al ic ▁acid ▁instead ▁of ▁the ▁base , ▁which ▁makes ▁it ▁effective ▁against ▁rust ▁st ains ▁rather ▁than ▁gre ase ▁and ▁other ▁organ ic ▁d irt . ▁ ▁History ▁A bras ive ▁pow ders ▁have ▁been ▁used ▁to ▁was h ▁off ▁gre ase ▁and ▁other ▁hard ▁st ains ▁since ▁anti qu ity . ▁Bath ing ▁in ▁ancient ▁Greece ▁and ▁Rome ▁started ▁with ▁rub bing ▁the ▁body ▁with ▁fine ▁sand ▁mixed ▁with ▁oil ▁or ▁other ▁subst ances , ▁and ▁then ▁sc rap ing ▁it ▁off ▁with ▁a ▁special ▁cur ved ▁sp at ula , ▁a ▁str ig il . ▁▁ ▁The ▁plants ▁in ▁the ▁genus ▁E quis et um ▁(" hor set ails ") ▁are ▁also ▁called ▁" sc our ing ▁r ush es "