For iron-rust stains on white washable materials one of the agents given below should be used. In the case of colored materials, the effect of the agent should be tried first on a sample or in an inconspicuous place.
1. Hydrochloric acid, made by diluting the strong acid with an equal volume of water. Spread the stained place over a bowl of hot water and apply the acid drop by drop until the stain turns bright yellow; then immerse at once in hot water and rinse thoroughly. Repeat the treatment, if necessary. Add a little ammonia or borax to the last rinsing water to neutralize any acid which may remain in the goods.
2. Oxalic acid, in saturated solution, used in the same way as hydrochloric acid in No. 1. Or apply the crystals directly to the stain and moisten.
3. Cream of tartar. Boil the stained place in a solution of 4 teaspoon-fuls to 1 pint of water, until the stain disappears. This agent, owing to its cost, is practicable only for stains upon small articles which can be immersed and boiled in a cup or two of solution, though it may be used in the case of larger, articles by holding them above the solution in such a way that only the stained portion is immersed.
4. Lemon juice. Spread the stained place over a vessel of actively boiling water, and then squeeze lemon juice on the stain. After a few minutes rinse the stain and repeat the process. This method is rather slow but does not injure delicate white cotton or linen fabrics.
5. Lemon juice and salt. Sprinkle the stain with salt, moisten with lemon juice, and place in the sun, adding more lemon juice if necessary.
6. Acid fruits or vegetables. Those mentioned below are satisfactory and have the advantage of being found in the home garden or easily purchased. Others cannot be used because their juices are so highly colored as to leave stains themselves on the fabric. The use of lemon juice has been described above.
(a) Rhubarb stalks. One stalk, cut up and boiled in one cup of water, gives a solution strong enough to dissolve iron-rust. If the stalks have highly colored skins peel them before using. Boil the stain in the solution for 15 minutes or longer, if necessary.
(b) Begonia. Place several leaves, together with the stems, in a saucepan with only enough water to keep them from burning. Boil the stain in the infusion until it disappears.
(c) Pineapple. Cut up a round slice, about one-half inch in thickness, and boil with enough water to keep it from burning. Boil the stains for five minutes or until they disappear.
(d) Grapefruit. Use the pulp and juice from one-fourth of a fresh grapefruit in the same way as the pineapple.