1719. A New Wash for Wool and Silk

1719.     A New Wash for Wool and Silk. Instead of using the fumes of sulphur, M. Frezon proposes the following mixture: 4 pounds oxalic acid, 4 pounds table salt, 200 quarts water. The goods are laid in this mixture for an hour. They are then generally well bleached, and only require to be thoroughly rinsed and washed. For bleaching straw it is best to soak the goods in caustic soda and afterwards to make use of chloride of lime or Javelle water. {See Index.) The excess of chlorine is afterwards to be removed by hyposulphite of soda, called anti-chlor.

1720. To Bleach Straw Bonnets

1720.     To Bleach Straw Bonnets. Get a deep box, air-tight, if possible; place at the bottom a stone, on the stone a flat piece of iron red hot, or a pan of charcoal, on which scatter powdered brimstone; close the lid, and let the bonnet remain a night. There should be hooks on the box, on which to hang the bonnets. {See last receipt.)

1721. To Bleach Sponge

1721.     To Bleach Sponge. Sponge may be bleached almost snow-white by repetitions of the following process: Soak it in diluted muriatic acid 10 or 12 hours, then wash it with water and immerse in a solution of hyposulphate of soda to which a small quantity of diluted muriatic acid has been added. "Wash and dry it.

1722. Blanched Sponge

1722.    Blanched Sponge. Soak the sponges for several days in cold water, renewing the water and squeezing the sponges occasionally. Then wash them in warm water, and place them in cold water to which a little muriatic acid has been added. Next day take them out and wash them thoroughly in soft water; then immerse them in an aqueous sulphurous acid (specific gravity 1.034) for a week. They are afterwards washed in plenty of water, squeezed, and allowed to dry in the air.

1723. To Bleach Lac

1723.     To Bleach Lac. Dissolve the lac in a boiling lye of pearlash or caustic potash, filter it and pass chlorine through the solution until all the lac is precipitated. Collect the precipitate, wash well in hot water, and finally twist into sticks, and throw them into cold water to harden. Lac thus purified is used to make pale varnishes and the more delicate tints of colored sealing-wax. Shellac bleached by this method is liable to stain furniture inlaid with brass. The following process is free from this objection, and has the additional advantage of being much cheaper:

1724. To Bleach Shellac with Animal Charcoal

1724. To Bleach Shellac with Animal Charcoal Any quantity of yellow shellac, previously broken in small pieces, is conveyed into a flask, alcohol of .830 specific gravity poured upon it, and the whole heated on a stove, or, in the summer, in the sun, until the shellac is dissolved; upon this so much coarsely powdered animal charcoal is added to the solution that the whole forms a thin paste; the flask is closed, not quite air-tight, and left so for some time exposed to the sun; and in 8 to 14 days a small sample is filtered, sufficient to ascertain whether it has acquired a light yellowish brown color, and whether it yields a clear, pure polish, on light colored woods. If this be the case, it is filtered through coarse blotting paper, for which purpose it is best to employ a tin funnel with double sides, similar to those employed in filtering spirituous solutions of soaps, opodeldoc, etc.. The portion which first passes through the filter may be preserved separately, and used as a ground or first polish. Then some more spirit is poured over the charcoal upon the filter, and the solution used as a last coating. The solution of shellac purified by animal charcoal has a brown yellow color, but it is perfectly clear and transparent; when diluted with alcohol, the color is so slight that it may be used in this state for polishing perfectly white wood, such as maple, pine, etc.. without the wood acquiring the least tint of yellow.