In the numerous chemical formulae a subscripted number is shown as _{2}, so the familiar formula for water would be H_{2}O: H, subscript 2, O. This notation is needed to distinguish digits that are subscripts from digits that are multipliers, as for example in the formula Pb(OH)_{2}2PbCO_{3}, where the subscript 2 must be distinguished from the quantity multiplier 2 that follows it. _Director of the New York State School of Clay-Working and Ceramics_ ¶ _Some time a Superintendent in the Royal Porcelain Works, Worcester, England_…
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