Page:The Art of Bookbinding, Zaehnsdorf, 1890.djvu/212

172 from rusting; the oil forms a coat over them which excludes contact from air. Dissolve ½ oz. of camphor in 1 lb. of lard; take off the scum, and mix as much blacklead as will give the mixture an iron colour. All kinds of machinery, iron or steel, if rubbed over with this mixture, and left on for 24 hours, and then rubbed with a linen cloth, will keep clean for months. To clean silver mountings.—To restore the colour of tarnished silver clasps, etc., boil the goods, either silver or plated, in enough water to cover them. For every pint of water put into it 2 ounces of carbonate of potash and a ¼ lb. of whiting. After boiling them for about a quarter of an hour, clean with a leather, brush, and whiting. They will then look as good as new.

To clean sponges.—Soak the sponge well in diluted muriatic acid for twelve hours. Wash well, then immerse in a solution of hyposulphate of soda to which a few drops of muriatic acid has been added a few moments before. When sufficiently bleached, wash well, and dry in a current of air.