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THE STRAND MAGAZINE.

into the world. The pounds (if you have any), the shillings, and the pence which you carry in your pockets are the result of a combination of experience and skill which you, perhaps, little suspect.

When the bullion—the metal in its pure state—arrives at the Mint, it is assayed—that is, tested. It is then passed on to the Melting-room, and, together with the baser metal which forms the alloy necessary to reduce it to the proper standard, placed in the crucible, or melting-pot. Let us take the coining of silver as an example. The crucible used is made of mixed clay and graphite, each vessel holding about three thousand ounces. On two sides of the Melting-room are coke furnaces, and into one of these the crucible is dropped.

Here it remains until the metal is at a molten heat, when it is lifted by means of a crane on to an apparatus shown in our illustration. This forms a pretty sight. The crucible is red-hot, and the boiling metal, as it is stirred vigorously by one of the men with an iron rod, emits a lovely bluish flame. The apparatus tilts the pot, and the metal runs into a series of moulds which move on a carriage underneath. These moulds being well oiled, the metal has no chance of becoming part of them. The bars formed in this way are twelve inches long and three-eighths of an inch thick. When removed from the moulds their edges are ragged, but a revolving file soon makes them smooth, and the bars are ready to be again assayed. A piece is chipped from one of them, and if the necessary standard of fineness has been secured, the bars pass to the next department.


In the rolling-room.

This is the Rolling-room. The metal, it must be understood, is far from hard, and the reduction of the thickness and consequent increase in the length, due to the rolling of the bars, are not so difficult a matter as to the uninitiated they may seem. The bars are placed between adjustable cylinders and rolled into strips, or "fillets" as they are called.

They pass several times through the machine, being reduced the one-nineteenth part of an inch in each rolling at first, but, finally, only the one-hundredth part of an inch. Naturally the process makes the metal very hard, and it has to be annealed—that is, heated and softened—constantly until it is the right thickness. We need only state that the strips from which half-sovereigns are made must not vary more than 1-20,000th part of an inch—in other words, they must be within 1-10,000th part of an inch of the nominal thickness—to