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laminating engine, which, by being brought gradually closer to each other, give the plates an even and exact thickness. The workman then makes use of a steel instrument, called a trepan: it is hollow, and of a roundish figure, with sharp edges, to cut out as many planchets, or circular pieces of metal, as the plate contains. In order to prepare these planchets for receiving the designed impression, they are compared with standard pieces, to see if they are of proper weight. Then the superfluous part of the metal is filed or scraped off; and lastly, they are boiled and made clean, before they are conveyed to the machine for marking them upon the edge. The principal pieces of this machine, are two thin plates of steel, about a line thick. One half of the inscription is engraved on the thickness of one of the plates, and the other half on the thickness of the other. These sheets of steel, or laminæ, as they are called, are straight, although the planchets to be marked with them are circular. One of these lamina is fixed straight with screws, whilst the other slides by means of a dented wheel. When
they stamp a planchet, it is placed between the laminæ in such a manner, that the edge of the planchet may touch the two lamina on each side, and that each of them, as well as the planchet, lies flat upon a copper-plate, which is fastened upon a very thick wooden table. The sliding lamina causes the planchet to turn, so that the edge receives the impression when it has made one turn. Crown and half-crown pieces, only, are thick enough to bear inscriptions on their edges. The coining engine, or mill, puts the finishing stroke to the piece. This machine is so commodious, that a single man may stamp twenty thousand planchets in one day. Gold, silver, and copper, are all of them coined with a mill, to which the coining squares, commonly called dies, are fastened: that of the face beneath, in a square box fastened with screws; and the reverse above, in a little box fitted in a similar manner. The planchet is fixed upon the square of the effigy, so as to receive an impression on both sides, in the twinkling of an eye, by turning the mill once round. Thus completed, the coin un
dergoes an examination of the mint-wardens, who are officers appointed for that purpose, and then is ushered into circulation. I fear my account is scarcely clear enough to be understood; but it is the plainest I can give you, unless you could see the machine.
CECILIA. I comprehend it very well. MRS. HARCOURT. The same process is observed in the coining of medals; but with this difference, that money requiring but a small relievo, is perfected at a single stroke of the engine; but for medals, it is obliged to be repeated several times, for the sake of heightening the relievo. Between each stroke the planchet is taken out from between the dies, heated, and returned again, sometimes fifteen or twenty times. Medallions, and medals of a high relievo, are frequently cast first in sand, because of the difficulty of giving them a full impression in the mill, where they are put only to receive a delicate finishing, which the sand seldom gives them.
MR. HARCOURT. Until the reign of King William the Third, the British coin was made in a different manner; hammers being
used instead of the mill. The method then adopted was less commodious, not so expeditious, and in every respect inferior to that now in use. The perfection of this art was reserved for the late Mr. Bolton, of Soho, near Birmingham, where he constructed a most ingenious apparatus, at a large expense, capable of performing all the different operations of coining, as Sophia, who has seen it, will explain more particularly.
SOPHIA. The whole machinery is moved by an improved steam-engine, which rolls the copper for halfpence finer than copper has ever been rolled for the purpose of making money. It works both the coupoirs, or screw-press for working out the circular pieces of copper, and coins both the faces and edges of the money at the same time, with such superior excellence and cheapness of workmanship, as must prevent every attempt to imitate the coin in a clandestine manner; and, consequently, may prove the means of saving the lives of many unhappy persons from the hands of the executioner. By this machinery, four boys of twelve years
old are capable of striking thirty thousand guineas in an hour, and the machine itself keeps an unerring account of the number of pieces which are struck.
CHARLES. Ought not the invention of a machine of such important use, to have entitled Mr. Bolton to the honours of nobility? Titles can never be so nobly bestowed as in the reward of merit; and what merit can claim so large a recompense, as that which rescues our fellow-citizens from destruction?
MRS. HARCOURT. Merit was the original claim to distinction of rank; but in the present refined state of society, nobility is become hereditary, and has, in a great measure, ceased to be considered as the reward of personal virtue. As Mr. Bolton lived to see his machine adopted by government, and to be a witness of its beneficial effects, the reflection of having conferred a lasting advantage upon his country, must have been a greater satisfaction to him, than even the honour of a noble title. The time for repose is at hand. Let each one retire, with a mind disposed to humble gratitude for the blessings enjoyed in the past day. Adieu.