▁ 2 1 . 6 ▁parts ▁o xygen . ▁These ▁were ▁likely ▁tin ( II ) ▁ox ide ▁( S n O ) ▁and ▁tin ▁dio x ide ▁( S n O 2 ), ▁and ▁their ▁actual ▁compos itions ▁are ▁ 8 8 . 1 % ▁tin — 1 1 . 9 % ▁o xygen , ▁and ▁ 7 8 . 7 % ▁tin — 2 1 . 3 % ▁o xygen . ▁ ▁Sch ol ars ▁who ▁have ▁review ed ▁the ▁writ ings ▁of ▁Pr oust ▁found ▁that ▁he ▁had ▁enough ▁data ▁to ▁have ▁discovered ▁the ▁law ▁of ▁multiple ▁proport ions ▁himself , ▁but ▁somehow ▁he ▁did ▁not . ▁With ▁regards ▁to ▁the ▁a for ement ioned ▁tin ▁ox ides , ▁had ▁Pr oust ▁adjust ed ▁his ▁figures ▁for ▁a ▁tin ▁content ▁of ▁ 1 0 0 ▁parts ▁for ▁both ▁ox ides , ▁he ▁would ▁have ▁noticed ▁that ▁ 1 0 0 ▁parts ▁of ▁tin ▁will ▁combine ▁with ▁either ▁ 1 4 . 9 ▁or ▁ 2 7 . 6 ▁parts ▁of ▁o xygen . ▁ 1 4 . 9 ▁and ▁ 2 7 . 6 ▁form ▁a ▁ratio ▁of ▁ 1 : 1 . 8 5 , ▁which ▁is ▁ 1 : 2 ▁if ▁one ▁forg ives ▁experimental ▁error . ▁It ▁seems ▁this ▁did ▁not ▁occur ▁to ▁Pr oust , ▁but ▁it ▁occurred ▁to ▁Dal ton . ▁ ▁Foot notes ▁ ▁Bibli ography ▁ ▁Category : Phys ical ▁chem istry ▁Category : Sto ichi ometry <0x0A> </s> ▁My ke ▁Cole ▁is