Important: Safety Warning
This page describes trade processes that use dangerously toxic materials such as cyanide solutions, mercury amalgams, or strong acids. These processes require training, equipment, and precautions far beyond what the text describes.
This information has been left in for historical purposes but should not be acted upon.
Home › Recipes › To restore old Writing that is nearly defaced
To restore old Writing that is nearly defaced
Boil one ounce of powdered nut-galls, for an hour or more in a pint of white wine; filter the liquor, and when cold, wet the paper with it, or pass it on the lines with a camel-hair pencil, and the writing will be much revived. To paint a Picture that will appear and disappear occasionally. To half an ounce of nitric acid, add one drachm of cobalt, one drachm of muriate of soda, and two ounces of water; set it in a sand bath, or on warn ashes, where it must remain five or six hours Then filter the solution, (which is nitro-muriate of cobalt,) and with it draw the trees, and shrubber' of a designed picture. Then with a solution of oxide of cobalt in acetic acid, draw some distan mountains, fences, &c. and with muriate of copper draw some flowers, buildings, &c. These will all be invisible when dry; but warm the paper and the picture will appear in green, blue and yellow. It will disappear when the paper becomes cold.