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Removal of Spots and Stains: Oxalic

Oxalic Acid. - This is the active principle of salts of sorrel. When combined with cream of tartar it is known as salts of lemon. It may be dissolved in one part of boiling water.

It is a dangerous poison, and in certain quantities will cause death in about ten minutes. It is used for cleaning leather, scouring metals, especially brass and copper, and for removing various stains. It has very much the appearance of Epsom salts, from which it must be carefully distinguished.

Use of Oxalic Acid. - Oxalic acid is especially useful in the laundry to remove iron mold, fruit stains, and ink spots produced by the old style irongall inks. It does not, however, remove ink stains produced by modern writing fluids or blue-black inks composed of aniline dyes. Oxalic acid may be applied to cotton, linen, woolen, silk, or any ordinary fabric if uncolored, but it bleaches colored goods. The color, can, however, in most cases be restored by aqua ammonia. When possible, it is advisable to experiment with a sample of the goods before applying oxalic acid to colored articles. To Apply Oxalic Acid. -The acid may be applied alone, either dissolved in its own bulk of boiling water for "saturated" solution, or in nine parts of cold water for a "dilute" solution.

Or, as salts of lemon, it may be dissolved in 1 to 10 parts of water, either hot or cold. The action of the acid is increased by heat as in boiling water.

To apply, either wet the spot in water and cover with dry oxalic acid or salts of lemon, or dip the spot into the solution, or apply the solution to the spot with a small brush, sponge, or piece of rag. If the stains are old or have penetrated through the fabric it will be necessary to rub the acid vigorously into the spot and persist patiently until successful. Oxalic acid is also recommended to bleach silk in the proportion of 4 pounds of the acid and 4 pounds of salt to 2 quarts of water for the raw silk, or 2 ounces of oxalic acid and 2 ounces of salt to 6 quarts of water for white silk that has become yellowed from washing.

The latter proportions may be observed for removing vegetable or fruit stains, should it be necessary to immerse the article in the solution. As soon as the stain disappears, rinse with clear water, and afterwards wash with soapsuds. Uses of Citric Acid. - This is the acid principle of alum and lemon juice; it is also found in gooseberries, currants, and some other fruits. It is intensely sour, is readily soluble in water, and is used in medicine; in dyeing, to heighten certain colors, and to break up certain coloring compounds. Citric acid may be used dissolved in slightly more than its own bulk of water for a saturated solution, or in 10 or more parts for a dilute solution. It may be applied to white goods or fast-dyed cotton or woolen, by moistening the stain with a solution by means of the finger tips, a small brush, sponge, or rag. Rinse immediately in clear water. It may be used for stains from fruit, irongall inks, iron rust, or mildew; but for these oxalic or tartaric acids are commonly preferred. In the form of lemon juice, citric acid is a mild but useful agent, and one generally employed. With the addition of salt on colored goods it may safely be used on any ordinary fabric. To apply, saturate the spot with lemon juice, and for colored goods cover with dry salt. Expose to direct sunshine and repeat if necessary.

Or apply lemon juice and salt, and steam the fabric over a kettle.

Uses of Lactic Acid. - This is the acid which forms in milk when it turns sour and which is, therefore, contained in buttermilk. It is the presence of this acid which causes buttermilk to be employed in the process of bleaching linen. Sweet milk, sour milk, and buttermilk are all recommended for the treatment of stains in fabrics, the action being strong in proportion as the liquid sours with age. Hence, when stains are fresh they may be removed by dipping immediately in warm milk; but when they are more stubborn, they may require soaking in buttermilk for some time. The addition of common salt increases their effectiveness. This is a simple and useful means of treating ink stains from iron-gall inks, tea stains, red-wine stains, and fruit stains, especially when fresh. Sour buttermilk also erases mildew. Wet or soak the article in fresh or sour milk or buttermilk, cover with common salt-which contains chlorine, a powerful bleaching agent-and expose to sunshine in the open air.