18. To take Stains out of Marble.—Mix unslaked lime in finest powder with stringent soap-ley, pretty thick, and instantly with a painter's brush lay it on the whole of the marble. In two months' time wash it off perfectly clean; then have ready a fine thick lather of soft soap, boiled in soft water; dip a brush in it, and scour the marble. This will, with very good rubbing, give a beautiful polish.
19. To take Iron-stains out of Marble.—An equal quantity of fresh spirit of vitriol and lemon-juice being mixed in a bottle, shake it well; wet the spots, and in a few minutes rub with soft linen till they disappear.
20. Mixture for cleaning Stone Stairs, Hall Pavements, &c.—Boil together half a pint each of size and stone-blue water, with two table-spoonfuls of whiting, and two cakes of pipe-makers' clay, in about two quarts of water. Wash the stones over with a flannel slightly wetted in this mixture; and when dry, rub them with flannel and a brush. Some persons recommend beer, but water is much better for the purpose.
21. To Color or Paper the Walls of Rooms.—If a ceiling or wall is to be whitewashed or colored, the first thing to be done is, to wash off the dirt and stains with a brush and clean water, being careful to move the brush in one direction, up and down, and not all sorts of ways, or the work will look smeary afterwards. When dry, the ceiling is ready for whitewash, which is to be made by mixing whiting and water together, till quite smooth, and as thick as cream. Dissolve half-an-ounce of glue in a teacupful of water, stir it into the whitewash. This size, as it is called, prevents the white or color rubbing off the wall, and a teacupful is enough for a gallon of wash. Stone color is made by mixing a little yellow ochre and blue black with the size, and then stirring it into the whitewash; yellow or red ochre are also good colors, and, with vermilion or indigo, any shade may be prepared, according to taste.
If paper is to be used, the wall must be washed with clean water, as above explained; and while wet, the old color must be scraped off with a knife, or a smooth-edged steel scraper of any sort. It will be best to wet a yard or two at a time, and then scrape. Next, wash the wall all over with size, made with an ounce of glue to a gallon of water; and when this is dry, the wall is ready for the paper. This must be cut into lengths according to the different parts of the room; one edge of the plain strip must be cut off close to the pattern, and the other left half an inch wide. If the paper is thick, it should lie a minute or two after it is pasted; but if thin, the sooner it is on the wall, the better. Begin by placing the close-cut edge of the paper at one side of the window, stick it securely to meet the ceiling, let it hang straight, and then press it down lightly and regularly with a clean cloth. The close-cut edge of the next length will cover the half-inch left on the first one, and so make a neat join; and in this way you may go all round the room, and finish at the other side of the window.
22. Damp Walls.—Damp may be prevented from exuding from walls by first drying them thoroughly, and then covering them with the following mixture: In a quart of linseed oil, boil three ounces of litharge, and four ounces of resin. Apply this in successive coats, and it will form a hard varnish on the wall after the fifth coating.