Clean articles bright with sulphuric acid. Having made all parts clean, wash in a solution of sal-ammonia, and dry them in sawdust or by heat; but be sure they are dry before bathing in metal or the metal will fly. You next require a large pot (a glue pot is just the thing), with two compartments, the inner one being perforated to hold the articles to be tinned and the outside one for the metal. Powder your articles with sal-ammoniac and dip them in the molten metal, which should be free from dross; after all smoke has disappeared, lift the inner compartment out, i. e., the one that contains the articles, and sprinkle some more sal-ammoniac over them, also a little over the molten metal, this preventing them from being coated too heavily. When you have reached the same heat as the metal, take them out and shake well to get surplus solder off and cool rapidly in water, drying in sawdust to preserve their lustre. Very small articles can be tinned with a soldering iron and brushed off with a brush, but whichever way is adopted care should be taken to have the articles perfectly clean before starting, and be sure that you get the articles good and hot or the coating of metal will peel off when cold.