I Quite a number of the different salts of silver have been used in forming preparations for silver plating by this method, which, by the way, hardly merits the name of silver plating, as but a very thin film of metal can be deposited with¬out the aid of a battery, but for small articles of ornament not subject to much hard usage this process of silvering answers very well. Most of the salts of silver are made from the nitrate, which is formed by dissolving small fragments of silver in a warm mixture composed of one part of water and four or five parts of the strongest nitric acid. Care must be taken that the liquid is not too hot nor the silver added too rapidly, or it will boil over and a portion of it be lost. Should it threaten to do so, add a small quantity of cold water. The whole operation should be conducted in the open air or where there is sufficient draft to carry off the noxious fumes that arise from the mixture while the silver is being dissolved. When it will dis¬solve no more metal it should be evaporated and crystalized. The resultant* salt is nitrate of silver, which should be kept in a well stoppered bottle protected from the light. The chloride is formed by adding a solution of common salt to a solution of nitrate of silver, until it will no longer form a precipitate, which should be care¬fully filtered and washed and be protected from the light. This salt is more frequently used in making compounds for silvering without a battery, than any of the other salts.
This process is more particularly adapted to the plating of small articles, where they are not subject to much wear, and consequently only a very thin coating of silver is required; the deposit looking fully as well as articles plated by the battery process.
The following solutions we have selected from a large number as being the most economical ; and at the same time, simple and efficacious, and are used by adding sufficient warm water to them to form a thin paste, and rubbing it over the articles with a soft rag, or stirring them about in it until they have become thoroughly coated. 1st. Take equal parts of chloride of silver and cream of tarter. 2d. Take common salt and cream of tarter each six parts, chloride of silver one part and about two parts of alum. A good liquid solution is made by dissolving in boiling water a mixture composed of chloride of silver one part and cream of tarter sixty or eighty parts. The articles to be plated should be placed in a small basket and immersed and stirred around in the boiling liquid.
The above mentioned solutions can only be used for plating articles of brass, copper or Ger¬man silver, or articles of other metals that have previously received a coating of copper. The liquid solution, after continued use, becomes of a greenish color, caused by the presence of cop¬per, dissolved from articles that have been plated in it. The presence of the least particle of iron, steel, lead or brittannia metal, causes the copper to be deposited, thus spoiling the appearance of the articles. An old solution, however, will work much better than a new one, provided it has been well taken care of and has been properly managed, and it may be renewed b> occasionally adding small quantities of chloride of silver, and thus kept in good order for a
long time. In using these solutions, as well as all other- plating solutions, the articles to be plated must first be made very clean and smooth, and the solutions kept at a uniform temperature.
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