If to be tinned on one side only, first smear with salt and water the opposite side; then, with a pad of tow, wash the other side with killed spirits (chloride of zinc), and also sprinkle a little powdered sal-ammoniac over the surface. Place the sheet over the fire, and when hot enough, rub the end of a strip of tin on it until a small portion of the tin melts; then, with a pad of tow or wadding, on which some powdered sal-ammoniac has been sprinkled, rub the molten tin over the hot surface, and continue this operation until the whole surface is covered. If the copper is to be tinned on both sides, an iron bath of semicircular section, built up over a firegrate, should be used.

Having melted a sufficient quantity of tin in the bath, pass the copper sheet through it, and as it is withdrawn, quickly wipe the superfluous tin from each side with a, pad of tow. The surface of the copper should be first prepared as described above.