Scientific American 35, 20.5.1848
This may be made much cheaper than purchased, as follows: - two drachms of nitrate of silver, added to a weak solution of tincture of galls. Another. - Nitrate of silver, one drachm, mixed with a solution of half an ounce of gum arabic in half a pint of pure rain water. Moisten the cloth previously with a strong solution of pearl, or salt of tartar, and iron it dry.
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