1559. Balard's Waterproofing for Clothing

1559.     Balard's Waterproofing for Clothing. Balard recommends the application of acetate of alumina for the purpose of rendering clothing impervious to water. The cloth is to be immersed in a mixture of solutions of acetate of lead and sulphate of alumina; by mutual decomposition of the salts, acetate of alumina is produced on the cloth, and when the goods are dried, basic acetate of alumina adheres to the fibre, and thus protects it from the action of moisture. The process is particularly recommended for military goods.

1560. Berlin Waterproof Cloth

1560.    Berlin Waterproof Cloth. A firm in Berlin has for some years furnished a completely waterproof cloth, the process for making which has been kept a secret. It is now stated, however, that the method consists, in all probability, in saturating the cloth at first with a solution of sulphate of alumina and of copper, and then immersing it in a bath of water-glass and a solution of resin soap. The object of the copper seems to be to prevent the cloth from rotting or stiffening more perfectly than can be done by the alumina alone. (See No. 15G1.)

1561. To Waterproof Linen, Canvas, etc.

1561.  To Waterproof Linen, Canvas, etc.. Three baths arc prepared as follows : The first, by dissolving 1 part neutral sulphate of alumina (concentrated alum cake) in 10 parts cold water. For the second, boil 1 part ligrht resin. 1 part soda crystals and 10 parts water, till the soda is dissolved; add 1/8 part common salt, to separate the water and collect the soap; dissolve this soap with an equal amount of good palm-oil soap in 30 parts water. This soap bath must be used hot. The third bath consists of water only. Soak the fabric thoroughly in the first, or alum bath ; next pass it through the soap bath; and lastly, rinse in the water. (See No. 1560 (Berlin Waterproof Cloth).)

1562. Metallic Soap

1562.    Metallic Soap. Metallic soap in linseed oil is highly recommended for coating canvas for wagon covers, tents, etc., as being not only impermeable to moisture, but remaining pliable for a long time without breaking. It can be made with little expense, as follows: Soft soap is to be dissolved in hot water, and a solution of copperas (sulphate of iron) added. The sulphuric acid combines with the potash of the soap, and the oxide of iron is precipitated with the fatty acid as insoluble iron soap. This is washed and dried, and mixed with linseed oil. The addition of dissolved India rubber to the oil greatly improves the paint.

1563. To Render Canvas Fire and Waterproof

1563.    To Render Canvas Fire and Waterproof. Tents, awnings, canvas, etc., may be made fireproof as well as waterproof, by immersion in soluble glass diluted with boiling water to 25° Baum'e Before thoroughly dry, immerse in a solution of sulphate of alumina (alum cake) and sulphate of cop-per (blue vitriol), 1 part of each to 10 parts of water; then dry the fabric slowly in the air.

1564. Fireproofing Fabrics

1564.    Fireproofing Fabrics. A solution of 3 parts borax and 21/2 parts sulphate of magnesia in 20 parts water is recommended. Or a mixture of sulphate of ammonia and sulphate of lime. Soluble glass is applicable to rendering wood and theatrical decorations less inflammable.