Quicksilver.—See Mercury.
Rotten Stone.—A soft stone used for fine grinding and polishing. Generally used after pumice stone, and is applied with a soft woolen cloth and sweet oil.
Salts of Tartar.—See Potash.
Sandarac.—A resin that exudes from tree growing in Africa. Fusible by heat and soluble in alcohol. Used in varnishes.
Sesqui-Chloride of Iron.—See Iron, Sesqui-chloride of.
Shellac.—Lac is a resinous substance produced mainly from the banyan tree of the East Indies. It is the product of an insect. Stick lac is the resin in its natural state; seed lac when broken up, cleaned of impurities and washed; shellac when it is melted and formed in thin flakes. United with ivory-black or vermilion it makes sealing wax. Dissolved in alcohol it makes lackers and varnishes.
Silver, Nitrate of.—See nitrate of silver.
Soda.—Common. See potash.
Spanish Whiting.—Ground chalk carefully cleaned from all stony matter.