Firing the letters
The disk containing the enameled letters is taken at the end of a long iron handle and carefully placed in a dome-shaped muffle. These muffles are all heated from the outside; that is, the fire is all round the chamber, but not in it, the fumes of the sulphur being destructive of the enamel if they are allowed to come into contact with it. So intense is the heat, however, that a muffle lasts only about nine days, and at the end of that time has to be renewed.
Mixing the enamel
Mixing the enamel
The Blacksmith
The Blacksmith
Dusting the letters before firing
The letters are now taken charge of by a girl, who lays them out on a wire tray, the hollow side up, and paints them over with a thin mordant. While they are in this position, and before the mordant dries, they are taken on the gridiron-like tray to a kind of large box, which is full of the powdered enamel, and, holding the tray in her left hand, the girl takes a fine sieve full of the powder and dusts it over the letter, all superfluous powder falling through the open wirework and into the bin again, so that there is absolutely no waste.
Filing the letters after enameling
This is done by girls, who, with very fine files, rub off the edges and any protuberances which may be there. Every letter is subject to this operation, and all are turned out smooth and well finished.