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To Frost Silver (Article has to be carefully)

The article has to be carefully annealed either in a charcoal fire, or with a blowpipe before a gas flame, which will oxidize the alloy on the surface, and also destroy all dirt and greasy substances adhering to it, and then boiled in a copper pan containing a solution of of dilute sulphuric acid--of 1 part of acid to about 30 parts of water. The article is then placed in a vessel of clean water, and scratch-brushed, or scoured with fine sand; after which the annealing or boiling-out is repeated which will in most cases be sufficient to produce the desired result. If a very delicate dead surface such as watch dials, etc., is required, the article is, before the second annealing, covered with a pasty solution of potash and water, and immediately after the annealing, plunged in clean water, and then boiled out in either sulphuric acid solution, or a solution of 1 part cream tartar and 2 parts common salt to about 30 parts of water. If the article is of a low quality of silver, it is well to add some silver solution, such as is used for silvering, to the second boiling out solution. If the article is very inferior silver, the finishing will have to be given by immersing it in contact with a strip of zinc in a silver solution.