The wonders of the world

by John Loraine Abbott

THE UNITED STATES MINT IN PHILADELPHIA.

The United States mint was founded in 1790; and the business of coining commenced in 1793, in the building now occupied by the Apprentice’s library. In 1830, it was removed to the fine building it now occupies, on Chestnut street, above Olive street. The edifice is of white marble; and the north front, opposite to Penn square, is one hundred and twenty feet long, with a portico of sixty feet long, having six Ionic columns; while the south front, on Chestnut street, has a similar portico. Since the enormous influx of gold from California, the United States mint has become an object of more than common interest and attention; and the place is usually filled with visitors, watching the various processes the metal goes through before it comes out in finished coin. The machinery and apparatus by which these are accomplished, are of the most complete and perfect character. The rooms in which the smelting, refining, and alloying are done, are spacious apartments in which a large number of workmen are employed. Heaps of the rich ores are to be seen lying around, just as they were extracted from the mines, or gathered in dust from the sands of the mountain-streams of California. Bars of the pure metal, of thousands of dollars’ value, are passing through hands, which like those of the fabled Midas, seem to turn all they touch into gold. The heat of this place is very great; the fires glow with the intensity of those in a foundery; the men, in appearance, resemble the workmen in a smithy; and there is a suffocating sensation of hot air, steam, and perspiration, penetrating the atmosphere, which is anything but pleasant to experience, especially when one is palpitating under the heat of a summer temperature, without the freshness of the open air to modify and alleviate it. Crucibles are handled with iron tongs, and cotton or woolen mittens; and the metal is shaped into bars, and then reduced to the requisite fineness. All this takes place in one apartment.

In another room, is seen a most beautiful steam-engine, which drives all the rolling and stamping machinery. It is of one hundred horse-power, and works the rolling machinery, the draw-benches, and the cutting presses. It is called a steeple-engine, and has two cylinders; its boilers are forty feet long, and forty inches in diameter; and the steam from them also moves a ten horse, and a five horse engine, in the separating and cleaning apartments. This main engine is of the most elegant workmanship, polished like a piece of cutlery, and works with the most admirable precision and regularity, without the least perceptible jar, and with scarcely a noise. From this room, the visitor walks into that where the rolling machines are at work, turning out the metal to the proper degree of thickness which each particular kind of coin requires. The metal is cast into ingots fourteen inches long, and about five-eighths of an inch thick; and these are rolled to very near the proper thickness, when they are passed through the draw-benches to equalize them. The strips are then cut at the presses, which is done at the rate of about two hundred to two hundred and sixty per minute. There are fourteen men employed in this room, two at each pair of rolls. The pieces, as thus cut, then pass to the adjusting room, where each piece is weighed separately, and if too heavy, filed down, or if too light, or any way imperfect, thrown back to be remelted. There are fifty-four females employed in this room. The pieces are next taken to the milling and coining room, where from two hundred to four hundred are milled in a minute, according to their size. In another apartment, the coins are cut with a punch to the desired size, and then stamped. For this purpose they are placed, by a person seated at the machine, in a perpendicular tube, down which they descend, one at a time, being seized as they drop by a part of the machinery, which pushes the coin under the stamp, whence it falls beneath the machine into a glass-covered box. This part of the process used formerly to be performed by a press which required eight men to work its lever and screw; but now the process requires scarcely any manual labor except handling the various pieces of coin. The rapidity with which the pieces are executed, is surprising; being at the rate of from seventy-five to two hundred per minute. Cents, dimes, dollars, eagles and double-eagles are turned out with equal facility, the process being the same in all. Some idea of the extensiveness of these operations may be had, when it is stated, that, in a single month, lately, nearly three million pieces of gold, silver and copper were coined, and that over four million dollars in value are coined every month.

In addition to the other attractions of the mint, there is a most extensive cabinet of coins, ancient and modern, of various nations, which is one of the greatest of curiosities to be found, probably, in any part of the world. Here, too, are exhibited specimens of all the existing or past coins of the mint itself, and models or specimens of any intended coins. The officers and attendants of the mint are polite and attentive to all visitors, and endeavor to make their visit one of instruction as well as amusement; and any one, by calling at appointed hours, can go through the various apartments of the building, and see the various processes which have thus been described.