Lac Sulphuris, Milk of Sulphur - is prepared by boiling sublimed sulfur with slaked lime and water, forming the sulphide and hypophosphite of calcium, which are then decomposed by HCl, and sulphur is precipitated as a very fine powder which is then washed until the washings are tasteless, and dried with a gentle heat.  Chiefly used as a laxative.