Fuller's soap: (Heb. borith mekabbeshim, i.e., "alkali of those treading
cloth"). Mention is made (Prov. 25:20; Jer. 2:22) of nitre and
also (Mal. 3:2) of soap (Heb. borith) used by the fuller in his
operations. Nitre is found in Syria, and vegetable alkali was
obtained from the ashes of certain plants. (See SOAP T0003467.)