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carriage back to the starting-place, ready for another strip.

The original machine was invented by Mr. Barton, Controller of the British Mint; but this table has been so far improved by Mr. Peale as to be almost his own creation. Barton's table required two men to operate it, while Peale's requires only one. The arrangement of the combination weights to draw back the carriage, fast at first and slower as it reaches the starting

tongs and attach the carriage to the chain, are Mr. Peale's invention. His machine is arranged to run with much less noise than Barton's, and has other minor improvements.

table. At the right end you see an iron box | secured to the table. In this are fastened two perpendicular steel cylinders, firmly supported in a bed, to prevent their bending or turning around, and presenting but a small portion of their circumference to the strip. These are exactly at the same distance apart that the thickness of the strip must be. One end of the strip is pinched somewhat thinner than the rest, to allow it to slip easily between the cylinders. When through, this end is put between the jaws of a power-point; the application of the pedals to close the ful pair of tongs, or pincers, fastened to a little carriage running on the table. One carriage you see has a flag fastened to it, and has drawn a strip nearly through. The carriage to the further bench is up close to the cylinders, ready to receive a strip, which is inserted edgewise. When the end is between the pincers, the operator touches a foot pedal which closes the pincers firmly on the strip, and pressing another pedal, forces down a strong hook at the left end of the carriage, which catches in a link of the moving chain. This draws the carriage away from the cylinders, and the strip being connected with it has to follow. It is drawn through the cylinders, which, operating on the thick part of the strip with greater power than upon the thin, reduces the whole to an equal thickness. When the whole is through, the strain on the tongs instant-ting more plainly, we will examine them. ly ceases, which allows a spring to open them and drop the strip. At the same time another spring raises the hook and disengages the carriage from the chain. A cord fastened to the carriage runs back over the wheel near the head of the table, and then up to a couple of combination weights on the wall beyond, which draw the

Just turn around and we shall see the next process the strips undergo, after being washed free from grease or wax in warm water. Round pieces, called planchets, a little larger than the coins they are to make, are being cut from them. Four cutting presses of one kind are in a row; but more being required, Mr. Peale constructed two on about the same principle, but much more compact and handsome. An outline of one of them can be seen in the fore-ground of the engraving "Drawing Bench." They are not, however, quite so conveniently adjusted as the old ones; and as these show the mode of opera

The press consists of a vertical steel punch, which works in a round hole or matrix, cut in a solid steel plate. The action of the punch is obtained by an eccentric wheel. For instance, in an ordinary carriage wheel the axis is in the centre, and the wheel revolves evenly around it. But if the axis is placed, say four inches from the

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centre, then it would revolve with a kind of hobble. From this peculiar motion is its name derived. Suppose the tire of the wheel is arranged, not to revolve with, but to slip easily around the wheel, and a rod is fastened to one side of the tire which prevents its turning. Now as the wheel revolves and brings the long side nearest the rod, it will push forward the rod, and when the long side of the wheel is away from the rod, it draws the rod with it.

The upper shaft, on which are seen the three large

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wheels, has also fastened to it, over cach press, an eccentric wheel. In the first press will be seen three upright rods running from near the table to the top. The middle one is connected with a tire around the eccentric wheel, and rises and falls with each revolution. The eccentric power is very popular among machinists, as it gives great rapidity of motion with but little jerking.

ECCENTRIC WHEEL.

CUTTING PRESSES.

The operator places one end of the strip under the punch and cuts out a couple of planchets, which are a fraction larger than the coin to be struck. As the strips are of uniform thickness, if these two are of the right weight, all cut from the strip will be. They are therefore weighed accurately. If right, or a little too heavy, they are allowed to pass, as the extra weight can be filed off. If too light, the whole strip has to be remelted. The strips that are correct are quickly cut up, the press striking 220 double eagle planchets, or 250 smaller pieces, in a minute. A man has cut over a million dollars in double eagles in a single day. As fast as cut the planchets fall into a box below, and the perforated strips are folded into convenient lengths to be remelted. From a strip valued at about

eleven hundred dollars, eight hundred dollars of | planchets will be cut. They are still in a very rough, ragged state, and look but little like coin. The second press, rather smaller than the rest, is the first introduced, and has been in constant use for about forty years; has never been broken, or had fifty cents' worth of repairs done to it.

under her arms to catch any gold that may fall. In short sleeves, to avoid sweeping away the dust, and armed with a fine flat file, she is at work, chatting and laughing merrily. She catches a double eagle planchet from a pile by her side and puts it into the scale. It is too heavy. She files it around the edge, and weighs it. Still too heavy. Files it again, and weighs it.

Right; the index is in the centre. She tosses it into the box, and picks up another to undergo the same operation.

We will leave this room, and go into a much more cheerful one for a moment, to see the sort-Almost right. Just touches it with the file. ing of the planchets. They are thrown upon a table with two holes in it, and a woman picks out all the imperfect pieces or chips, which are slipped into one hole, and the perfect ones into the other, where they fall into different boxes. It is not much to see; so come into the entry, up the marble stairs to the second story, past the Director's room, out upon a gallery looking down upon the court-yard below. At the further end of the gallery we pass through a small entry, and enter a room. What a peculiar noise, like a young ladies' school at recess, only a strange filing sound withal! Nearly sixty females, some young and pretty, some-middle-aged and finelooking. Jessie will have to do the examination: we can not stand the hundred and twenty eyes brought to a focus on us.

She tells us it is the Adjusting Room. Each operator has on the table before her a pair of assay scales. Seated close to the table, a leather apron, one end tacked to the table, is fastened

The proper weight of the double eagle is 516 grains, and the smaller gold coins are in the same proportion. Absolute perfection is impossible in the weight of coin, as in other matters, and the law therefore allows a variation of one half of a grain in the double eagles; therefore, between a heavy and a light piece, there may be a difference of one grain. This is so slight, however, not two cents in value, as to be deemed sufficiently correct. The weight of the silver half dollar is 192 grains, and smaller pieces in proportion, with the exception of the cent, which, being composed of 88 per cent. copper and 12 per cent. nickel, the weight is 72 grains. The weight of the silver coin was reduced in April, 1853. Prior to that date the half dollar was 2061 grains.

To adjust a coin so accurately requires great

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delicacy and skill, as a too free use of the file would quickly make it too light. Yet by long practice, so accustomed do the operators become, that they work with apparent recklessness, scarcely glancing at planchet or scales, but seemingly guided by their touch. Our artist attempted to obtain a photograph of the room while they were at work, but it was found impossible for fiftyfive out of the sixty to remain quiet long enough for the camera to operate. It was necessary to take the room after they had left, supplying the figures in the drawing.

The exceedingly delicate scales were made under the direction of Mr. Peale, who greatly improved on the old ones in use. So delicate are they that the slightest breath of air affects their accuracy, rendering it necessary to exclude every draft from the room, which, being poorly ventilated, in a hot day is an uncomfortable and probably an unhealthy place. Colonel Childs, the late chief coiner, exercised great care to counteract this difficulty by occasionally stopping work, and opening the windows. The whole process, however, is behind the times. Hand-work can not compete with machinery. Sixty adjusters can not keep the coining presses supplied, and genius must find a quicker way of performing the work. It is here that the delay occurs, keeping depositors waiting from twenty to thirty days for the coin they should receive in a week. It is astonishing that our Mint has not made the advancement here that it has in every other department.

Only the gold pieces are adjusted in this manner. The silver has merely the adjustment of the two planchets weighed at the cutting press. A greater alJowance is made in the weight of silver coin, as it is less valuable, and it would be almost impossible to have such a vast number of small pieces separately examined. Mr. Peale ordered from Paris a beau

tiful and delicate coin-separator, which he intended to apply to silver (although the one received is adapted to the half eagle only), but owing to its not arriving until he had been removed it has never been put in operation. It is so arranged that the planchets, being placed in at one end, are carried through the hopper and dropped singly on a balance. If too light it is tipped into a box at one side; if too heavy, into another box; if exactly right, into a third box. The instrument does not adjust the weight, but merely separates the heavy and light planchets. For silver, however, this would be desirable, as a more uniform weight could be preserved. Why it has never been put in use we are unable to learn.

The females in the adjusting room are paid

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MILLING MACHINE.

#1 10 a day for ten hours' work. They look happy and contented. Behind the screens, at each end of the room, are dining-halls, where they eat the dinners they bring with them. On the whole, it is the pleasantest work-shop for women we have yet seen, and the pay, in comparison with that ordinarily given to women, is good.

If you examine a double eagle, or, lacking one, a quarter of a dollar, a slight rim will be noticed around the edge, raised a little higher than the device. It is done to prevent the device being worn by rubbing on counters, etc., and also that the coins may be piled one on another steadily. This edge is raised by a very beautiful piece of mechanism called a Milling Machine, the invention of Mr. Peale, and vastly superior to any other in use.

Some twenty or thirty planchets are placed in one of the brass vertical tubes, of which there are three, for different sized coins. At the bottom of the tube the lowest planchet is struck by a revolving feeder, which drives it horizontally between the revolving steel wheel (marked A in the engraving) on one side, and the fixed segment (marked B) on the other. The segment is on the same curve as the wheel, though somewhat nearer to it at the further end. The planchet is caught in a narrow groove cut in the wheel and segment, and the space being somewhat less than the diameter of the planchet the edge is crowded up about the thirty-second part of an inch. The planchet makes four revolutions when it reaches the end of the segment, and being released from the grooves falls into a box below. The edge is perfectly smooth, the fiuting or "reeding," as it is termed, being put on in the process of coining. The work is so nimbly performed that about one hundred and twenty double eagles, or five hundred and sixty half dimes, can be milled in one minute. This is a vast improvement on the English milling machine, worked by hand, and operating on but two planchets at a time.*

The curious copper machine, looking like a large revolving squirrel-cage, is the drying-drum. About half of it is a tight copper drum, into which the blanks from the hot water are placed with a quantity of basswood saw-dust. Steam is introduced through the axis to heat the interior, and the drum made to revolve, causing the blanks to roll among the heated saw-dust and dry themselves. Basswood dust is used because of its freedom from sap, pitch, or gum of any kind. It is extremely pure. In the language of one of the men, "It ain't got nothing about it but just wood."

When the blanks are dry a door in the end of the drum is opened, allowing them to fall into the sieve, where they tumble about, the dust gradually sifting out, leaving the coin clean. To brighten them they are kept revolving for an hour, and the friction of one upon another gives them a beautiful lustre. It is in this way that pins, brass buttons, and the like are polished.

They are taken from the drying-drum, and heated in a large warming-pan, with steam-pipes running under it, until Jessie would hardly hold a handful for the gift of them, though they are all double eagles. They are now ready for coinage, and that prettily painted truck is taking a couple of hundred thousand dollars to the other room for the purpose.

Before examining the coining we must visit the Die Room, to learn how the dies are made. A coin has an impression on both sides, requiring, of course, a die for each. These are to be made with extreme care, to be of the finest workmanship, and all exactly alike. Their manufacture is one of the most important operations in the Mint.

Look at the bas-relief of Liberty on one side of a coin. It would be exceedingly difficult to design this in hard steel and of so small a size; so they first make the design in wax, probably six times as large as the coin, by which means the beautiful proportions can be obtained. From this a brass cast is taken, and reduced on steel to the size of the coin by a transfer or reducing lathe. This ingenious instrument was introduced from France by Mr. Peale, who also op

The planchets being milled are called blanks. They are very dirty and discolored by the processes they have undergone, requiring to be polished before coining. This is done in the Whit-erated it for some time. ening Room, and an exceedingly hot place it is. Sometimes in summer the thermometer will indicate 120', though the tall man by the furnace declares that it is often at 175°. The room is too small and poorly ventilated for the use to which it is put. There are two furnaces for annealing the blanks, they being placed in a copper box, with a cover sealed on air-tight with clay. Boxes and blanks are heated red-hot, and the blanks tipped into a vat containing a weak solution of sulphuric acid and water, to cleanse them. The stream of water in the other vat is hot, in which the blanks are washed free from the acid, leaving them a beautiful white color, almost like silver.

A full description of the English process of coining, with engravings of the machinery, can be found in "En

cyclopedia Britannica," article "Coinage."

The brass cast is fastened to the large wheel at the right-hand side of the lathe. On the small wheel to the left of the cast is fastened a piece of soft steel, on which the design is to be engraved. Both of these wheels revolve in the same way and at the same speed. There is a long iron bar or lever fastened by a joint to an iron support at the extreme left, which runs in front of the two wheels. A spring at the upper end draws it in toward the wheels. Fastened to the lever is a pointed steel stub, which touches the cast. A very sharp "graver" is fastened to the lever below, which touches the steel. The wheels revolve, and the stub, when it is pushed back by the heavy relief of the cast, forces back the lever, which draws back the graver, and prevents it cutting the steel. So where there is a raised place in the cast the graver is prevented from cutting

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