originally the salt (chiefly composed of magnesium sulphate) obtained from Epsom water; subsequently a common name for magnesium sulphate however…

Used attributively in Seidlitz salt n. Obsolete magnesium sulphate. Seidlitz water n. Obsolete an artificial aperient water of the same composition…

Short for Epsom salt n.

Native magnesium sulphate.

Hydrous magnesium sulphate, usually occurring in fine, granular, white masses, in the salt-mines at Staßfurt, Saxony-Anhalt, Germany and elsewhere…