Some hard woods do not readily take a black color from the application of a single staining fluid, but require to be treated with two different decoctions, of of which the following are typical: Dissolve 6 to 8 ozs. extract of logwood in 1 quart of water by boiling, and add 1/4 drachm of alum; stir the fluid and apply this to the wood, giving one, two, or three applications as required to produce a deep stain. When the second is nearly dry give an application of " iron liquor" (see No. 1); repeat the application of the iron liquor until a deep color is obtained.
With very hard woods it is often requisite to steep the wood in the coloring solution or even boil the wood in it. But it will be found in such cases that a spirit stain is preferable to an aqueous one; the spirit will penetrate the fiber much better. To prevent the stain being abstracted when the wood is polished or varnished it should be sized with a thin solution of gluu size before applying the polish. Two ounces of good white glue in 1 pint of water will be sufficient. Soak the glue for several hours in cold water and then melt it by heating in a glue pot with the remainder of the water and apply when cooled, or else allow to set to a jelly and rub the jelly size into the wood and let it dry before varnishing. The size may be colored with a little of the dye liquor that has been used for staining the wood.
No. 4. - A good black spirit stain is obtained by dis solving 1 oz. of sheeline and 1 oz. of nigrasin in 1 pint of methylated spirit, i. e., alcohol metholated with acotone, not with mineral oils, and apply several applications ot this until the surface is a deep black ; the dye liquor can be applied hot, but as hot fluids are lia ble to raise the fiber of the wood, a light sand papering with No. 0 sandpaper will be necessary, and if the abrasion thus caused shows signs of cutting into the black stain, that is, if it allows the color of the wood to appear beneath the black stain, a final application after sandpapering, of cold stain must be given; then size and varnish the wood as directed in No. 1.
No. 5. - A good black staining compound, to be used on all kinds of wood, and as a final application, is to dissolve 4 ozs. of logwood extract in 1 quart of water and add 1/4 oz yellow chromate of potash while heating; then allow the mixture to rest a few days until it thickens slightly; the fluid thus applied will form a good black surface, There are many other formula for producing black stain on wood, but the above will suffice for all the needs of the amateur.-"Hobbies," London.