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Webster 1913 Edition
Epsom salt
{
. Ep′som saltsˊ
orEp′som saltˊ
}(Med.)
Sulphate of magnesia having cathartic qualities; – originally prepared by boiling down the mineral waters at
Epsom
, England, – whence the name; afterwards prepared from sea water; but now from certain minerals, as from siliceous hydrate of magnesia.