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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 alumphate of alumina (concentrated alum cake) in 10 parts cold water. For the second, boil 1 part light resin, 1 part soda crystals and 10 HONEY. parts water, till the soda is dissolved add 1/80 dered galls, heated to boiling, and then mixed 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.)