1902 Encyclopedia > Mint


MINT. The mint is the place where the coinage of a country is manufactured, and whence it is issued by sovereign authority, under special conditions and regulations. The privilege of coining has in all ages and countries belonged to the sovereign, and has, in England at least, been rarely delegated to any subject, and in any case in a restricted form, the crown always reserving the right of determining the standard, denomination, and design of the coins.
At a very early stage of civilization it was found necessary to have some definite medium of exchange, in order to avoid the great inconvenience arising from the system of payment in kind, which was the primitive and natural method. It was not long before metal came to be used as such a medium, probably from its durability and portability, and in the case of gold and silver on account of their intrinsic value. The less liable the value of a metal is to change the better is it suited for a standard of value.
Though historians assure us that metals were found in
Britain at a very early period, there does not appear to be any evidence that the mines were worked until consider-ably later than the time at which the use of metal as a medium of exchange was introduced. It is probable there-fore that the metals for exchange were imported into Britain long before the native mines were developed.
The metals chiefly used were silver and brass, which were at first simply exchanged by weight for commodities of all kinds. As commercial transactions became mora numerous and more complicated, this system of payment grew troublesome, and it was found convenient to divide the mass of metal into small parts, which soon took the form of rough coins. But the principle of payment by weight was retained through many centuries, and is per-petuated, though in name only, in the word " pound."
Records of attempts to organize the coinage of England are found as far back as the Anglo-Saxon period, and it is known that on the dissolution of the Heptarchy the mints were regulated by laws framed in the witenagemot. The first monarch who appears to have dealt successfully with the organization of the coinage was Athelstan, who framed laws for the regulation of the mints, and appointed officers whose titles and duties are then first recorded. The only officers connected with the coinage of whom mention is found before this time are the "moneyers," who appear to have been alone responsible for the manufacture of the coin; but it is probable that even then there existed some officer who had authority over them. In early Saxon and Norman times the number of moneyers was considerable, mints being established in almost every important town, as might be expected at a period when communication between distant places was extremely difficult. They appear to have been the officers who actually performed the work of making the coin, the mint master in later times contracting with them, at a high rate, for the work. They were respon-sible for the purity and perfection of the coins produced, as appears from the fact that it was they who were punished (as traitors) in the case of any deficiency in weight or fineness. They had prescriptive rights in the coinage, and in modern times (even so late as 1850) claimed to have corporate privileges; but it is clear, on the authority of Ruding, that they never were a "corporation" separate from other officers of the mint. The number of mints was greatly reduced after the Norman Conquest, but continued to be considerable until the reign of Richard I., when the work of coining for the whole kingdom was con-centrated in the mint in the Tower of London. Only one provincial mint (Winchester) remained till a later date.
An important reorganization of the coinage took place in 1325 under Edward II., the regulations then framed for the manufacture and issue of the coins forming the basis of those still in force. The principal officers under these regulations were—master, warden, comptroller, king's assay master, king's clerks, and cuneator. The office of cuneator was one of great importance at a time when there existed a multiplicity of mints, since he had the sole charge of all the dies used not only at the mint in the Tower of London but also in the provinces. He chose the engravers and presented them to the barons of the exchequer in order that they might take the oath of fidelity; he superintended their work, and was generally answerable for the perfection of the dies before they were issued for use in the various mints of the country. The office, which was hereditary, ceased to exist when the provincial mints were suppressed. In its place was instituted the office of clerk of the irons, whose functions were more limited, and were not hereditary. This office was only recently abolished.
In the Middle Ages an important duty devolving on the officers of the mint was the collection of the seigniorage which was levied on the coining of money, not only for the purpose of covering the expenses of minting, but also as a source of revenue to the crown which the sovereign claimed by virtue of his prerogative. In former times the collection of the seigniorage was entrusted to the warden, who also superintended the manufacture of the coins, so far as to ensure the proper relations between the moneyers on the one hand and the state on the other. He does not appear, however, to have had any responsibility with regard to the fineness and weight of the coins.
The king's assay master was specially charged with all matters relating to the accuracy of the standard. The officer next in rank to him was the comptroller, who presented annually to the barons of the exchequer a report of all the gold and silver money struck in the kingdom during the year. These reports, which were always written upon parchment, constitute the chief mint records. The king's clerk exercised a general superintendence and kept an account of all the mint transactions. As the work of the mint became more extensive and more complicated, other officers were added such as the surveyor of the meltings, surveyor of the money presses, and many others.
The present arrangements with regard to the officers of the mint were made in 1870, when several important changes took place in the mint establishment. Up to that time there had been two controlling officers,—the master, who in some instances was selected on account of distinguished scientific attainments (as in the cases of Sir John Herschel and Professor Graham), and the deputy master and comp-troller. A careful inquiry, however, having led to the conclusion that the control of the mint might with advantage be concentrated in the hands of a single officer of experience in the conduct of public business, it was decided, on the death of Professor Graham, to entrust the actual administra-tion of the department to the deputy master,—the office and title of master of the mint being held by the chancellor of the exchequer for the time being, without salary. At the same time the services of a scientific officer were secured, by the appointment of a chemist of the mint. The coining and die department and the melting depart-ment were united under the name of the operative depart-ment, and placed under a single superintendent. The first deputy master appointed under the new regulations was the Hon. C. W. Fremantle', C.B., to whom the public are indebted for a series of Annual Reports which have given a new and increased interest to the subject of the coinage, and may be said to constitute in themselves a mint literature.
The actual operations of coining in early times were few in number and simple in character. The metals forming the alloy were melted together in the proportion necessary to bring them to the required standard, and the alloy thus obtained was cast into bars, which were reduced by hammering to the requisite thickness. They were then cut with shears into pieces more or less regular in size and form, roughly annealed, and finally impressed with the prescribed device by a blow with a hammer.
The last-named appears to have been the only part of the process which was performed with any great amount of care. The blank piece was placed by the hand upon a die fixed into a block of wood having a large heavy base to resist the oscillation caused by the blow; the die on which was engraved the device for the reverse of the coin was then placed upon the upper side of the blank and held by means of a holder, round which was placed a roll of lead to protect the hand of the operator while heavy blows were struck with a hammer by an assistant workman. One of the earliest improvements in coining was the introduction of a tool in shape resembling a pair of tongs, the two dies being placed one at the extremity of each leg. This avoided the necessity of readjusting the dies between successive strokes of the hammer, and ensured greater accuracy in the impres-sion. It was long before the system of coining by hand was superseded by the coining press, or mill, which, even after its first introduction, was only very slowly adopted. Several attempts were made to introduce machinery for coining before it was brought into active use, the objection to it being its great expense. The mill and screw were finally introduced into the mint under Charles II., when many improvements were also made in the preliminary operations. Steam-power was first applied in 1810, when the vacuum screw-press was introduced. In 1839 Uhlhorn invented the lever-press, which still remains in use.
The subject of the design on coins, besides being inter-esting both from an artistic and an historical point of view, becomes very important when it is remembered that it is the impression of the coin with the authorized device which makes it legally current. The artistic merits of the design of the early Greek coins are well known, and prove that the dies from which the coins were struck must have been engraved with much skill and care. The form of the coins before being stamped was at first merely that of natural rounded nuggets of gold, or of the silver-gold alloy known as electrum. Such coined nuggets of gold are still to be found among the hill tribes of India. Simple nuggets were afterwards replaced by roughly-fashioned masses like half bullets, a form which rendered it easy to impart high relief to the obverse and comparatively low relief to the reverse of the coins. The early British coins had for their prototype the gold " stater" of Philip of Macedon, but the design of this beautifully finished coin was so roughly imitated by a succession of British copyists that ultimately the wreath round the head of the monarch alone survived, and that in a scarcely recognizable form. It is not only in the early British coins that the influence of classical art may be seen, for it is very evident in some of the present day, the most notable instances being the reverse of the bronze coinage, and the beautiful design of St George and the dragon by Pistrucci, which is still used as an alternative design for the sovereign. It has been ascertained that the impressions on the reverse of very early Greek coins were produced by the rough surface of the anvil or the nail head on which they were placed, while the obverse was struck with the die. A little later the device on the reverse of the coins was obtained by placing the blank piece on small points of metal arranged in geometrical forms which caused corresponding indenta-tions on the coins when struck with the hammer. The beauty and accuracy of design on coins gradually increased as art and manual skill developed, and probably culminated at the period of the Renaissance.
Although it has been the custom since the time of the Saxons to stamp coins with the head of the reigning monarch, it does not appear that any attempt at actual por-traiture was made in England until the reign of Henry VII., who, " about the eighteenth or nineteenth year of his reign, did make a great alteration in the form of his coin, upon which his head was now represented in profile, and with a good resemblance of his other pictures." Since then much care seems to have been taken to stamp the coins with a true likeness of the monarch. In most cases the heads bear a striking resemblance to the portraits drawn by the great artists of the respective periods, and were, indeed, generally designed by artists of eminence. Some of the Milan coinage of Louis XII. is said to have been designed by Leonardo da Vinci, and similar work is attri-buted to Benvenuto Cellini.
In very early times the silver coins were equal in weight and in tale, each penny weighing 24 grains or 1 penny-weight. The amount now denominated a pound was a pound weight of standard or sterling silver. This principle was in fact, however, not strictly adhered to, the coins frequently falling below the standard of weight. This deviation may possibly have arisen from the imperfection of the methods of manufacture, but Ruding (Annals of the Coinage) considers it to have occurred from design, as the deficiency in weight was sometimes made a source of profit. The deviation from the standard weight permitted by law, now called the " remedy," and anciently called the " shere," was taken advantage of to a large extent, so that the coins suffered considerable diminution, particularly when, as frequently happened, they were also "clipped" as soon as they were issued. When these coins were called in they were taken by weight and not by tale, so that the posses-sors suffered considerable loss. In later times the great improvements in the method of manufacture made it easy to attain far greater accuracy both of weight and fineness; consequently the remedy permitted by law has been con-siderably reduced, and the possibility of making a large amount of profit by this means proportionally diminished.
The seigniorage levied on the coining of money was not a fixed rate, but varied considerably at different times, and accrued from a deduction made from the bullion coined. It was abolished by an Act of Charles II., which provided that whoever brought sterling silver or standard gold to the mint should receive in exchange an equal weight of current coin, the expenses of coining being defrayed by means of duties levied upon certain commodities of common use. The seigniorage on silver was revived in the reign of George III., when that part of the Act of Charles II. which related to the coining of silver without charge was repealed, and another Act was passed, requiring every pound of silver to be coined into sixty-six shillings instead of sixty-two,—the four shillings realized on each pound of silver by this depreciation of its value being handed over to the master of the mint to defray the expenses of assay-ing, loss, and manufacture. An Act of William IV. required the seigniorage on the silver coinage to be paid to the credit of the Consolidated Fund, and the charges of the mint to be brought annually before parliament. Against the profit derived by the state from this source must be placed the expense of maintaining the silver coinage in a condition fit for circulation by frequently withdrawing, recoining, and reissuing the silver coins. A vote of ¿£15,000 is annually taken in the mint estimates for the loss on the recoinage of silver.
In former times the work of the mint was performed by contract, the mint master undertaking the manufacture of the coinage at a stated price, and paying the moneyers and other officers and workmen under him at a fixed tariff. The agreement made between the crown and the mint master, called the "master's indenture," was sometimes purposely kept secret. This system appears to have pre-vailed from the reign of Edward I., when an agreement _was entered into between the king and the first master of the mint (appointed about 1279). Under this agreement an allowance was secured to the master to cover all the ex-penses of coinage. Although the master of the mint ceased to be a contractor, the arrangement with the managers con-tinued in force up to 1851.
The work of coinage was transferred in 1810 from the Tower of London, where it had been carried on for many centuries, to the present Mint on Tower Hill, not far from the Bank of England. The head of the department, as has already been stated, is the chancellor of the exchequer for the time being, who is ex officio master of the mint,—the practical direction of the work being placed in the hands of a permanent officer, the deputy master, who is responsible for its due performance. From the English mint is supplied the coinage for the whole of the British empire, including the colonies, with the exception of Australia; the latter and the East Indies are supplied from branch mints estab-lished at Sydney and Melbourne, and the mints of Calcutta and Bombay. In addition to the gold, silver, and bronze coins current in the United Kingdom, the English mint strikes gold coins of the value of two dollars for New-foundland ; silver coins of the value of fifty, twenty-five, twenty, ten, and five cents respectively for Newfoundland and Canada; bronze pence and halfpence of special design for Jersey, and nickel pence, halfpence, and farthings for the West Indies. The number of coins of each separate denomination issued varies considerably in different years, the demand for special denominations of coin naturally determining the supply.
The following table (from official sources) shows the value of the gold and silver coins issued during the ten years 1871-81. The total value of the bronze coin issued in the same period is £112,890.

Date. Gold Coinage. Silver Coinage.

Sovereigns. Half-Sovereigns. Total Value. Half-Crowns. j Florins.
1872 1873 1874 1875 1876 1877 1878 1879 18S0 1881 £
13.643.8S5 2,382,S35 519,629
1,106,289 17,525 3,645,853 £
1,617,556 1,001,733
243,264 1,401,943
981,468 1,158,780 17,525
504,199 £
15,261,441 3,384,568 1,461,565 243.264 4,696,648 981,468 2,265,069 35,050 4,150,052 £
273,240 138,996 79,200 55,836 183,150 112,662 168,102 280,170 £
692,010 596,574 180,774 114,246 60,786 68,706 178,596 135,432 232,254 256,806

24,610,721 7,868,408 32,479,129 1,291,356 2,516,184

Date. Silver Coinage.3

Shillings. Six-pences. Four-
pences. Three-pences. Two-pences. Pence. Totals.
1872 1873 1S74 1875 187« 1877 1878 1879 1880 1881 £
443,322 324,324 275,022 217,800 3S.412 163,350 156,222 180,576 242,154 262,548 £
94,446 109,890 105,732 81,378 20,988 101,772 65,538 83,100 96,426 150,810 £ s. G9 6 69 6 69 6 69 6 69 6 69 6 69 6 69 6 69 6 69 6 £ s.
13,916 2 $0,744 2 55,694 2 41,438 2 22,826 2 31,142 2 30,350 2 37,082 2 22,430 2 40,646 2 £ s. 39 12 39 12 39 12 39 12 39 12 39 12 39 12 39 12 39 12 39 12 £
33 33 33 33 33 33 83 33 33 33 £
1,243,836 1,081,674 890,604 594,000 222,354 420,948 613,998 549,054 761,508 997,128

2,303,730 916,140 693 0 346,269 0 396 0 330 7,375,104
The British sovereign or twenty-shilling piece was first issued by proclamation dated 1st July 1817, superseding the guinea or twenty-one-shil ling piece. Crown pieces of the nominal value of five shillings were first struck in the reign of Henry VIII., six-pences and threepenny-pieces are first mentioned in the reign of Edward VI., while the groat or fourpenny-piece was coined as early as the reign of Edward I. ; the florin or two-shilling-piece was introduced in 1849. Copper money was first coined by Charles I. in 1665, but does not appear to have been issued until 1672. Copper was replaced by bronze in 1860.
The weight and fineness of the various denominations of coin struck at the Royal Mint is shown in the first schedule of the Coin-age Act (33 Vict. c. 10), 1870 :—

== TABLE ==

The weight and fineness of the coins specified in this schedule are according to what is provided by the Act 56 Geo. III. c. 68, that the gold coin of the United Kingdom of Great Britain and Ireland should hold such weight and fineness as were prescribed in the then existing mint indenture, that is to say, that there should be nine hundred and thirty-four sovereigns and one ten-shilling piece contained in 20 lb weight troy of standard gold, of the fine-ness, at the trial of the same, of 22 carats fine gold and 2 carats of alloy in the pound weight troy, and further, as regards silver coin, that there should be sixty-six shillings in every pound troy of standard silver of the fineness of 11 ounces 2 pennyweights of fine siiver and 18 pennyweights of alloy in every pound weight troy.
The present standard of fineness for gold, 22 parts fine or pure gold and 2 parts of alloyed metal, was finally adopted in the reign of Charles II., and has remained unchanged up to the present time. Before the passing of the Act determining this standard considerable changes had been made from time to time, the highest degree of fineness having been reached in the reign of Henry III., when the first gold coins were struck of the standard of 24 carats pure gold. The standard of fineness for gold at some different periods may be seen from the following table, which shows the _composition of some of the ancient gold trial plates, of which portions are preserved in the Mint:— afterwards fixed the standard at 22 carats ; and no variation in the legal standard has occurred since that time. The last new trial plates, made in 1873, were alloyed with copper only, in order that they might correspond with the composition of the British gold coins, former plates having been alloyed with silver and copper. At the same time supplementary plates of pure gold and silver were prepared in order that the greatest possible accuracy might be secured.
The present standard of fineness of silver for coinage was fixed at a very early period, but has been subject to considerable varia-tion since the reign of Edward I., the first English monarch who debased the silver coinage. In the reign of Henry VIII. it was once reduced as low as 4 ounces of silver to 8 of alloying metal, and Edward VI. reduced it even lower. It was restored by Elizabeth to the original standard.
Standard found by
The following table shows the composition of some of the ancient silver trial plates of which portions have been preserved in the Mint :—

== TABLE == ??

The earliest trial plate of which there is any record was made in the seventeenth year of Edward IV. Before that time it would seem that the coins were compared with others known to be of standard fineness, since among the Cotton MSS. is preserved the account of the trial of the pyx of gold nobles in 1349, when the coins were compared with an ounce of florins of Florence kept in the Treasury a,s standards. The first gold coins were 24 carats fine or pure gold. Edward III. caused coins to be struck of 23 carats 3J grains fine in 1345, but no trial plate of this standard was made until 1477. Henry VIII. lowered the standard to 22 carats, but caused coins to be struck both of that and the former standards. The greatest debasement of the standard ever reached in England was in 1546, when it sunk as low as 20 carats. It reached a low point in the early part of Edward VI.'s reign, but was raised towards the end of it to 22 carats ; and it was still further raised to 23 carats 3J grains by Elizabeth, who, however, caused gold coins of 22 carats also to be struck. Charles II. on his accession rejected the trial plates of the standard of 22 carats which had been made under the Commonwealth, and caused others to be made of the standard of 23 carats 3J grains. No coins, however, appear to have been struck of this standard. The same monarch inch, while in the later stages the reduction in thickness at each
passage through the rolls is less than To"oth of an inch, and finally
one or two " spring pinches " are given to the bars by simply pass-
ing them through the rolls without altering the adjustment. The
testing of the fillets, to ascertain whether they are of the accurate
thickness, is effected
by the aid of the gauge
plate (fig. 4), which
consists of two steel
bars set at a low angle
in relation to each
other and graduated
to Trnn.th of an inch. FlG- 4.—Gauge Plate.
It will be evident that the weight of the finished coin depends upon the thickness of the fillets ; and to show how accurately the rolling must be performed it may be pointed out that, in the case of the half-sovereign, a variation of -jTroTnrth 0f an inch, above or below the accurate thickness (or a range of ro-oTnfth, of an inch) throws the coin out of "remedy."
I _
The repeated passage through the rolls is attended by a consider-able increase of hardness in the metal, and it is therefore in some cases necessary to anneal the fillets repeatedly during the rolling. In the case of fillets for sovereigns the annealing may be entirely dispensed with if the initial thickness of the bars does not exceed f ths of an inch. Fillets for half-sovereigns have only to be annealed once. In some European mints the fillets are annealed frequently ; in one mint the operation is performed after each passage through the rolls. The furnace used for the purpose is generally so arranged as to permit the flame to play over the fillets, which are sometimes freely exposed to its action, but are more often enclosed in cases or tubes. Muffle furnaces are frequently used. The furnace used in the Royal Mint is a simple form of reverberatory furnace. The final rolling is given by a pair of finishing rolls capable of more accurate adjustment than the '' breaking-down " rolls.
The fillets of gold or silver are in some cases, though not always, Drag submitted to an appliance known as the drag bench, shown in bench, figs. 5, 6, 7. Its object is to equalize the thickness of the fillets by drawing them between steel cylinders. The ends of the fillet3 are

„ liijiBiiiy||1^3iBlllllj! I ||j|||B|§
Fig. 5.

Fig. 6.

FIGS. 5, 6, 7.—Drag Bench.

first flattened in a little appliance, which need not be described.
The essential feature of the
machine now used in the
mint consists of two small
steel cylinders A, A, which
do not revolve, and are
held in position in the
plates D, D by clamp pieces
F, F screwed against them.
The portions of metal may
be adjusted by the aid of
a wheel and screw IT (figs.
6, 7), and by small ad-
justing screws /, /. The
part of the machine con-
taining the steel cylinders
is fixed at the end of a
long bench, and gearing at
the other end of this bench
drives an endless chain BB
(fig. 6), one link or other of
which catches the carriage,
shown in plan in fig. 5, and
drags it along as soon as
its end / is depressed by
the handle r. The carriage
runs on the wheels d, d.
The drawing of the fillet
C is conducted as follows.
Its flattened end is intro-
duced between the steel
cylinders, and is grasped
by the jaws a. The jaws
turn on the pin c, and while
the fillet is being dragged
through the cylinders the
axle of the wheels d, d tends
to increase the grip of the FlG- 8.—Cutting Machine,
jaws by acting on their inclined ends. Directly the strain on the fillet is released, the pins i, i and the weight h loosen the jaws and at the same time raise the end of the carriage so as to arrest its further progress along the bench. The carriage is then moved forward by the handle s until the jaws enter the hollowed portion N and grasp another fillet.
Formerly—when fillets were rolled from thick bars—this appliance played a more important part in coining operations than at present. It is now only used for fillets from which sovereigns and half: sovereigns are to be produced. Before fillets are passed on to the next operation—that of cutting from them the disks or blanks destined to form the coin—they are carefully tested by a skilful workman called the "tryer," who cuts one or two blanks from the sides of Trying, each fillet by the aid of a cutter worked by hand. These blanks are weighed on a delicate balance against a standard weight, and the experience of the operator enables him to determine whether the variation from the exact weight will justify his sending the fillets for-ward to the cutting room. In any case he divides the fillets into two or more classes for a reason that will be explained presently.
The cutters employed in the mint until quite recently were of Cutting complicated construction, but these have been replaced by a simple blanks, machine (fig. 8) which, by the revolution of an excentric A, causes two short steel cylinders, mounted on a block of iron B suitably guided, to enter two holes firmly fixed in a plate on the bed of the machine. When the fillet FF is i
Fig. 9.
interposed between the short cylin-ders and the holes, the former force disks of metal through the holes, the fillet being advanced at each stroke of the machine by small gripping rolls C, C, C" actuated by a ratchet-wheel E, driven from the shaft which bears the excentric A. The disks pass down the tube G to a receptacle placed on the floor. In the ease of very large silver coins, only one disk is cut in the width of the fillet, and in some few mints disks for gold coin are also cut in this way, but it is far more usual to cut two disks in the width of the fillet, the position of the cutters being so arranged as to remove blanks in the manner shown in fig. 9. In cutting disks for bronze coin extreme precision is not necessary, and it has therefore been found possible to obtain five at each stroke of the
supposed to be the weight of coin which could be manu-factured in a day when the operations of coining were performed by the hand. The journey weight of gold is 15 B) troy, coined into 701 sovereigns or 1402 half-sovereigns. The journey weight of silver is 60 lb troy. From each journey weight a coin is taken and deposited in the " pyx " or chest for the annual trial. This is made by the freemen of the goldsmiths' company under the direction of the crown in the presence of the queen's remembrancer, who administers the oath to the jury and presides over the proceedings. The coins selected for trial are compared with pieces cut from trial plates of standard fineness, which are in the keeping of the warden of the standards, these pieces being assayed against the coins under examination. If the coins are found to be of the standard fineness and weight, within certain limits, a verdict to that effect is drawn up by the jurors and presented to the Treasury.
In consequence of the impossibility of ensuring an abso-lutely exact admixture of metals in coining, it has been found necessary at all times to allow to the mint master a certain margin, or " remedy," within which coins may vary in weight and fineness from the fixed standard and still be considered of the current standard. The remedy of fineness for English gold coin is now fixed at 2 parts per 1000. The great importance of maintaining the standard of fineness for gold will be evident when it is stated that the variation of of a millième (or thousandth part) above or below the standard causes a gain or loss of ¿100 in every million sterling. Gold coins would be within the remedy of fineness permitted by law if the amount of precious metal contained in them varied from 914-6 to 918-6 parts in 1000; and, although this remedy cannot be considered to be more than would meet occasional and unavoidable deviation from the exact standard, still, in the case of gold, but a very small part of the remedy of fineness is actually used, the coins seldom falling below 916-3 parts of gold in 1000, or rising above 917-0, while the mean composition of many millions of coins issued from the mint is often of the precise legal standard, 916-66. The remedy of fineness for. silver coin, which appears to have been always greater than that for gold coin, is 4 parts per 1000. The remedy of weight for gold is T6 per 1000 parts, that for silver 4T7, and that for bronze 20. Extreme care is taken to prevent the issue from the mint of any coins that exceed these permitted variations in weight and standard, each coin being weighed separately, and all those found to be above or below the standard being returned to the melting-house.
Since the real value of the gold coinage is the same as its nominal value, it is of the first importance that gold coins which are below the standard weight should not be allowed to circulate, otherwise holders of large quantities of gold coin are liable to considerable loss. After a certain amount of wear a gold coin in passing from hand to hand loses weight and becomes legally uncurrent. By the Coinage Act it is made compulsory for every person to "cut, break, or deface " any coin tendered to him in payment which is below the current weight, the person tendering it bearing the loss ; but, as no penalty is imposed for disregard of this obligation, the law is practically without effect. The withdrawal of light coin from circulation was formerly accomplished solely by the Bank of England, the mint regulations making provision for the receipt of gold tendered for coinage only in the form of bars. The bank undertook to purchase the light gold from the public at the rate of £3, 17s. 6|d. an ounce, a price which, as compared with the mint value of £3, 17s. 10Jd., entailed a loss of no less than 4d. an ounce on the seller. This loss was occasioned chiefly by the circumstance that the bank, being obliged before sending the light gold to the mint for recoinage to melt, assay, and cast it into bars, found it necessary to deduct the sum of 2|d. an ounce from the rate of £3, 17s. 9d. an ounce at which it was allowed by statute to purchase gold for coinage, in order to cover the expense of these operations and the loss incident to them. The heavy loss in price, added to that from deficient weight, occasioned constant disregard of the law requiring all light coin to be cut or defaced, and consequently a large amount of light gold continued to be circulated. After the passing of the Coinage Act in 1870, accordingly, fresh regulations were made, by which the mint authorities undertook to receive light gold coin for recoinage, returning to the importer the full mint value of =£3, 17s. lOJd. an ounce, thus reducing the loss to that arising from deficiency of weight only. As the Bank of England was enabled by these regulations to raise its price for light gold to the rate of ¿£3, 17s. 9d., the same rate at which it is bound to purchase ingots of standard, gold, greater inducements were offered to the public to send in light gold for recoinage, and its withdrawal from circulation was in consequence greatly facilitated. It is evident, however, that, as the deficiency in weight must entail some loss on the holders of light gold coin, they will be disposed to keep it in circulation as long as possible; consequently only a small proportion of the light gold received by bankers finds its way to the Bank of England and thence to the mint for recoinage. The result of some careful experiments made by. the late Mr Stanley Jevons, and published by him in the Journal of the Statistical Society (vol. xxxi. p. 426), showed that a sovereign becomes so light as to be legally uncurrent at the end of eighteen years. The last state measure taken for the withdrawal of light gold coin from circulation was the issue of a royal pro-clamation in 1842 calling attention to the laws and regulations relating to light gold coin, and instructing those persons whose duty it was to enforce them to see that they were carried out. From the beginning of July 1842 to the end of March 1845 £14,000,000 in light gold coin was withdrawn from circulation and recoined. This amount was estimated to represent 95 per cent, of the whole of the light gold then in circulation. In order to facilitate this withdrawal the Treasury had in June 1842 entered into arrangements with the Bank of England by which the bank was enabled to purchase light gold on behalf of the Government, at the full mint value of £3, 17s. 10|d. an ounce. Light coin, however, continued to be sent into the bank for some time after it had reverted to its original rate of payment for light gold, i.e., £3, 17s. 6 Jd. an ounce. The expense to the state of this withdrawal, including the expenses of recoinage, was £67,816. As no-important withdrawal of worn gold coin has occurred since that time, it is evident that a large amount of light gold must be at the present time in circulation, and that the loss in weight must be considerably greater than that of the coins withdrawn in 1842, the oldest of which were not more than twenty-five years old, the first issue having taken place in 1817. It has been proved by experiment that the average loss of weight in worn sovereigns and half-sovereigns now in circulation is about 3d. in each sovereign,"and that the deficiency in fineness of a large proportion of the coin amounts to about £400 per million. This deficiency arises from the trial plate of 1829, which determined the standard of a portion of the coins still in circulation, being itself below the legal standard. Taking the gold circulation at £100,000,000, of which about 50 per cent, is light, it is estimated that the amount to be recoined cannot be less than £50,000,000, on which the loss from deficiency of gold, both in weight and fineness, must be reckoned at about £650,000, independent of the expenses of recoinage. In the case of the silver coinage, the loss consequent on the withdrawal and recoinage of silver money is now covered 'by the seigniorage arising from the difference between the Teal and the nominal value of the coins. Before the adop-tion of gold as the sole standard of value, the conditions attending the withdrawal and recoinage of silver were much the same as those for gold. In the period between the reign of Charles II. and the accession of William III. the condition of the silver coinage became so unsatisfactory as to demand the attention of parliament. A recommendation made at the suggestion of Sir Isaac Newton for a recoinage of silver was at first. strenuously opposed, but was finally adopted. In the course of the discussion the question of raising the standard of weight and fineness arose, and this important change would probably have been made but for the representations of Locke, who warmly took up the question and convinced the Government of the desirability of preserving the established standard. In the great recoinage of silver, the loss arising from clipped and defaced coin was borne by the public, the money being raised by means of a special tax on glass windows. The silver reissued at this time amounted to £7,000,000, and the tax raised to cover loss and the expenses of coinage to £1,200,000. The work of this recoinage was so great that the resources of the mint in London were found to be unequal to the pressure put upon them, and therefore mints were either revived or established for the first time in a few of the large provincial towns. In addition to this ten furnaces were erected behind the Treasury at Whitehall to melt down the old pieces. By these means the renovation of the silver coinage was completed within the year. The new silver coins then issued were the first which had milled edges, the milling having been introduced in order to prevent clipping.
The mode in which the silver currency is distributed throughout the kingdom is explained by the late Mr George Forbes, cashier of the Bank of England, as follows :—
Every banker in the kingdom has a banker who is his agent in London. Every London banker has an account with the Bank of England. In the Bank of England there is a department devoted to the issue and receipt of silver coin. If in a district there is a _deficiency of silver currency, the bankers of the district are the first to find it out. They at once write to their London agents, who draw on their account with the Bank of England, and obtain what silver is required, which they send to the country banker. On the other hand, if there is a surplus of silver in a district it accumulates in the coffers of the local bankers, who send it up to their London agents, and they send it into the Bank of England. If there is a general demand for silver currency, the stock which the Bank of England endeavours to keep on hand becomes unduly diminished, and immediate notice of the fact is conveyed to the mint authorities, who proceed with all convenient speed to coin a supply of florins, shillings, sixpences, or of all of these coins, as the nature of the demand may require.
Gold bullion for coinage is supplied to the mint almost entirely by the Bank of England, the bank being bound by law to purchase at the rate of £3, 17s. 9d. an ounce any gold bullion of the legal standard which the public may bring for sale. Private individuals are permitted to bring bullion to the mint, and to receive back the full amount (at £3, 17s. lOJd. an ounce) converted into coin, free of any charge for loss or manufacture ; but, as they are subject to considerable delay, all " importations " of bullion being converted into coin in the order in which they are brought to the mint, the public practically prefer to sell their bullion to the bank, and receive its value without delay. In order to be accepted by the bank, the bullion must be cast into ingots and assayed, a guarantee being given by certain recognized assayers that the gold is of a certain standard fineness. This is known as the " trade assay." When the bank requires gold to be struck, due notice is sent to the deputy master, and on a fixed day the bullion is conveyed to the mint and delivered into his _custody. It arrives in the form of ingots, each weighing about 200 ounces, the aggregate value of each importa-tion being about £144,000. When the ingots arrive at the mint a small sample is taken from each and assayed, the result being sent to the authorities of the bank in order that it may be compared with that of the trade assay. If the bank authorities find that the two assays agree, within certain limits, as to weight and fineness, the ingots are immediately sent to the operative department of the mint to be converted into coin. The mint assay affords the basis for calculating the amount of copper, the alloying metal, that must be melted with the gold in order to produce the standard prescribed by law. The case of silver is somewhat different, the bullion being purchased by the department at its market value, which varies from year to year. During the ten years ending 1881 the average price of silver bullion sank gradually from 60y^-d. to 51yf-d. The silver bullion arrives at the mint in the form of ingots, each of which weighs about 1000 ounces, the value of each set of ingots varying considerably. The ingots, both of gold and silver, are weighed on a balance capable of turn-ing with 1 grain when loaded with 1200 ounces.
The operations of coining have undergone some slight changes with the introduction of new machinery and the increased extent of the Eoyal Mint, since the reconstruc-tion of the operative department in 1881. The plan (fig. 1) shows the present arrangement of the operative department.
The operations employed in the manufacture of gold and silver coin are as follows (incidental operations being printed in smaller type):—
I. Assaying the bullion.
II. Melting the metal.
(a) Addition of the amount of copper necessary to form the prescribed alloy; (b) pouring the metal into moulds so as to form bars ; (c) dressing these bars to remove rough edges and hollow ends ; (d) recovery of precious metals from crucibles and "sweep."
III. Assaying portions of metal cut from certain bars,
to ascertain whether sufficient accuracy has been attained
in the standard fineness.
IV. Eolling the bars into strips or " fillets."
Annealing the fillets (in some cases).
V. Adjusting the fillets by a final rolling, and in some
cases by the use of the drawbench.
Testing the fillets to ascertain whether they are of suffi-cient accuracy as regards thickness.
VI. Cutting out disks or blanks from the fillets.
Adjusting the blanks in weight (in some mints).
VII. Edge-rolling the blanks to produce a raised rim.
Annealing the blanks and (in some cases) "blanching"
or '' pickling " them in dilute acid.
VIII. Coining, or stamping the device on the blanks, by
means of engraved steel dies.
Milling the edges of the blanks or (in some cases) im-pressing a device, inscription, or ornament upon them.
IX. Weighing each coin, usually by the aid of automatic
X. Assaying and weighing pieces taken from the
finished coin before it is issued to the public.
The foregoing list will make it clear that the operations I of minting consist, not simply in the mechanical production of accurately adjusted disks of metal the purity alone of which has to be guaranteed, but in the formation of an alloy composed of precious and base metals in definite pro-portions. The accuracy of the " standard fineness " of the alloy after melting must be absolutely ascertained; the alloy must be protected during manufacture against a change of standard, and finally its correctness must be verified after it has been converted into coin.
The precious metals are weighed on entering the mint, as well as during various stages in the manufacture of coin. The finished coins are also weighed in bulk before they are issued to the public.
The operations incidental to the coinage of bronze and silver differ from those described in relation to gold in some unimportant details only; and the weight and composition of the bronze coins are not so carefully guarded as is the case with gold and silver.
Subjoined are the details of the operations involved in the conversion of bullion into coin at the British mint.
After being assayed and weighed in the manner af ready described Melting the bullion is taken to the melting-house, where the details of treat- the ment for silver and gold respectively differ somewhat. (The sub-_metal. sequent operations are nearly identical for both metals.) The silver melting-house (see fig. 1) contains eight furnaces, of the kind shown at A fig. 2, the part of the furnace containing the crucibles being below the lids B, B. Crucibles of cast iron were formerly employed, but these were replaced in 1853 by wrought iron pots, which have since 1870 been in turn abandoned in favour of crucibles made of a mixture of clay and graphite, each crucible being capable of containing about 3000 oz. Such crucibles are very generally adopted throughout the Indian and Continental mints, but the form and dimensions given to them vary. The fuel employed in England is coke, about 75 lb of which are re-quired to melt 3000 oz. of standard silver. Sufficient draught is. afforded by the flue C and by a chimney about 35 feet high which communicates with it. The silver and copper are melted together and before the metal is poured into moulds it is stirred with an iron rod having a flattened end. The surface of the molten metal is covered with a layer of charcoal to prevent oxidation of the copper. The crucible with its contents is then removed from the furnace by the aid of a crane and tongs "W", and is placed in a cradle M, which can be tilted by means of a handle D. By the interven-tion of toothed wheels E, F, G, H, and K acting on a rack the handle turns the crucible on the fulcrum formed by a spindle, so that the contents of the crucible may be poured into the moulds N mounted on a carriage OP, running on rails Q, Q. The moulds now in use in London are of such dimensions as to enable bars to be cast 12 inches long and f inch thick. The width of the bars varies, according to the coin to be produced, from If to 2f inches.
"When the metal has solidified in the moulds it is removed, and the bars are trimmed by the aid of a revolving circular fde, their ends being cut off and returned to the melting pot. Portions of metal are then cut from certain of the bars, and sent to the assay department. The bars are weighed before they pass to the subse-quent operations of coinage, in order that the amount of metal re-tained by the crucibles or carried into the flues may be ascertained. Gold bullion is melted in a similar way, but, the crucibles are smaller, and contain only 1200 oz. Their contents are poured by hand into moulds, one end of the tongs by which the crucible is grasped being supported by a chain and suspended from the roof. In many Continental mints it is very generally the practice to>. leave the crucible containing the precious metals in the furnace, and to pour the contents into the moulds by the aid of small ladles of wrought iron lined with clay.
It has been pointed out in GOLD (vol. x. p. 751) that minute quantities of certain metals render standard gold extremely brittle and unfit for coinage. If either the gold bullion or the copper used as an alloying metal should be impure, brittle bars will be the result. Should this prove to be the case, the bars are re-melted and chlorine gas is passed through the molten mass in the manner described in GOLD, vol. x. p. 750.
The engine-room (shown in fig. 1) contains three 60-horse-power vertical condensing engines, which are provided with Corlis valves, and are specially devised for meeting the constantly vary-ing strain to which they are subjected by the machinery, the whole of which they are capable of driving. The central engine acts directly on either or both of the rolling rooms placed on each side of the engine-house. There is, however, an additional 20-horse-power compound beam engine usually employed, in connexion with the pumps of a deep artesian well. Soiling. Into one or other of these rooms the bars which have been cast in the melting-house are brought, and are rolled into strips the thickness of which depends on the kind of coins to be produced. Gold is rolled in one room and silver or bronze in the other. The details of manipulation involved in the conversion of gold, silver, or bronze bars into coin, however, do not differ materially, and the coinage of sovereigns will therefore be taken as typical.
Each room contains six pairs of rolls, the diameter of the rolls varying from 10 to 14 inches. Smaller diameters are employed in most European mints, but on the other hand the use of very narrow rolls of far larger diameter has often been suggested, and there appears to be good ground for the belief that the rigidity of such rolls would enable strips or fillets of more uniform produced than is the case at present. The iron frame CC (fig. 3) is firmly bolted to the stone D, which rests on a solid foundation EE. This frame supports the two rolls A, B, the lower of which B revolves, but is not, like the upper, capable of adjustment in a vertical plane. The upper roll is centred in bearings, and may be raised or lowered by means of screws connected with toothed wheels F, F, which are turned by a handle G, both wheels being moved simulta-neously by worms on the rod H. The bearings of the upper roll are connected by vertical rods with weights below the level of the floor;
and, as it rises with the screws, it can thus be readily adjusted in a line exactly parallel with the lower roll, at a sufficient distance from it to admit the bar which is to be reduced to a strip or fillet. The rolls are turned by the shaft NN, the main wheel M, and the gearing K, L, 0, P. The sockets r by which the upper roll is connected with the gearing by the shaft I are not rigid, as is the case with the shaft Q of the lower roll, but admit of the adjust-ment of the roll. The portion of the roll used is determined by a guide a little wider than the bar. The rolls throughout this department are driven at the rate of about 32 revolutions in a minute. The iron frame CC is braced by rods a, s; and blocks bearing the driving shafts are shown at k, k, p, p.
The initial thickness of a sovereign bar is f ths of an inch. The bars are weighed out to the workmen in batches of about sixty bars, an entire batch being passed through the rolls under precisely the same conditions of adjustment. The bars are only slightly reduced in width by repeated

It will be evident that the rough classification of the fillets according to their thickness, to which reference has already been made, renders it easy to compensate for slight irregularities in thick-ness caused by rolling, by employing cutters of a slightly larger diameter than the standard size for fillets which are too thin.
The fillets after the removal of the disks present the perforated appearance shown in fig. 9. The residual metal, called "scissel," which amounts to from 25 to 30 per cent, of the metal operated upon, is returned to the melting-house in bundles weighing 180 oz. It may be mentioned here that all attempts to cut disks or blanks for coinage from the ends of rods or cylinders, and thus to avoid the production of scissel, have hitherto failed. Adius - '^ne next operation to which the blanks are submitted varies in merit, f different mints. In some, each blank is weighed by hand or by bl nks. automatic machinery, and each blank that is too heavy is adjusted either to an exact weight or to within the remedy prescribed by law. On the Continent it is very generally the practice to adjust blanks by the aid of a file, or by a machine that removes a fine shaving of metal from the surface of the blank. In mints where mechanical adjustment is adopted there is a tendency to produce '' too heavy " blanks in the rolling and cutting departments, as it is impossible to adjust blanks which are too light.'
In the London mint finished coin alone is weighed, so that the blanks after leaving the cutting room pass directly to an edge-rolling machine, which thickens the edge of each blank so as to form a rim intended to protect the impression on the finished coin. The operation of edge-rolling is called "marking," and the method of conducting it varies considerably in different mints.
In the Royal Mint the blanks are made to pass in quick succes-sion, at the rate of six hundred a minute, between a circular groove in the face of a revolving steel disk and a groove in a fixed block placed parallel to the face of the revolving disk. The groove in the block exactly corresponds to that on the disk; and, as the distance between the block and the disk is slightly less than the diameter of the blank submitted to the operation, the result is that before the blank escapes from the machine its edge has been thickened. The operation may be varied by admitting the blanks between a groove in the periphery of a revolving wheel and a groove in a segmented block, placed at a distance from the wheel rather less than the diameter of the blank. The wheel and block may be either vertical or horizontal.
In some cases the edges of the blanks, at the same time that they are thickened, receive the impression of a legend, or inscription, or an ornamental device. When this is the case the blank is rolled

Fig. 10.
between two planes, one of which is fixed and bears the device, while the other has a reciprocating motion imparted to it, or the edge of the blank receives the impression, which may be either raised
1 A description of a machine used for tile adjustment of blanks will be found in Dingier's Polytechnisches Journal (1882, ccxlv. 61, pi. 6); and some years ago Mr J. M. Napier devised for the Indian mints a beautiful machine which first ascertains how much it is necessary to cut from each blank in order to reduce it to the standard weight, and then removes the necessary amount of metal and no more. The initial cost of such machinery, however, is considerable. In 1849 M. Diereck, director of the mint in Paris, endeavoured to substitute a chemical for a mechanical treatment by submitting the heavy gold blanks to aqua regia, which it was anticipated would bring them within the prescribed limits of accuracy. The results were not satisfactory, and the attempt was abandoned. In 1870 the present chemist of the mint, Professor W. Chandler Roberts, showed that gold alloyed with copper might be removed from heavy blanks witii singular regularity by means of a suitable solvent aided by a battery. The blanks are arranged in a frame of wood and submitted to the action of a solution of cyanide of potassium, the heavy blanks forming the dissolving pole of the battery. The process was not used in the London mint, as it became evident that it could not profitably replace the present system, under which finished coins alone are weighed and the manufacture of good coin only is paid for. It was, however, introduced into the Bombay mint in 1870 by the late Mr L. G. Hines, who extended its usefulness by transferring the metal dissolved from the heavy blanks to blanks which are too light, the latter being by this means raised to the prescribed weight. The process has now fairly taken its place as an ordinary operation of coining, and its importance to the mints where it is used may be gathered from the fact that in the Indian mints no less than 1300 tons of silver were converted into coin in one year (1879), so that the saving effected by its introduction must be considerable.
or sunk, from a collar surrounding the blank in the coining press, as will be afterwards explained.
Before passing to the coining press the blanks either of gold or Anneal-silver are annealed. In many mints the object of the heating is ing the not only to soften the blanks before they receive the impression, but blanks, also to produce a film of oxide of copper on their surface. This is attained in various ways. In England gold blanks are placed in cylindrical crucibles of plumbago and covered with a layer of char-coal, heated in a reverberatory furnace, and when the blanks reach cherry-redness they are cooled by plunging them in water. The thin film of oxide of copper thus formed on the surface of the gold or silver blanks is readily soluble in dilute sulphuric acid, and the removal of a small portion of the alloying metal in this way con-stitutes "blanching" or "pickling" the coin. The method of conducting the operation varies somewhat in different mints, mainly, however, in the strength of the acid used, which varies from 3° to 5° of the hydrometer of Baume. The solution is sometimes heated to 96° to 98° O, while in other cases the blanks are intro-duced into the solution while at a red heat. The latter method is, however, objectionable, as a dense layer of pure metal is found at the surface of the blank which is apt to protect the underlying oxide of copper from the action of the acid. The blanks are afterwards washed in pure water and dried either in sawdust or in copper vessels heated by steam jackets. The object of the process is to improve the appearance of the finished coin by removing all traces of impurity from the surface of the blank. It has, however, been abandoned in the British mint except in the case of some of the smaller silver coins, mainly because the soft superficial layer of metal wears away with undue rapidity. Certain precautions suggested in 1869 by Mr Hill, the superintendent of the operative department, for avoiding oxidation or tarnishing of the metal during coinage rendered the abolition of the process possible. Coining The blanks receive the impression wdiich constitutes them coins press. from engraved dies. Each is placed in the lower of two dies, and the upper die is brought forcibly down upon it. The lateral escape of the metal is prevented by a collar which surrounds the blank while it is being struck. This collar may be either plain or engraved, and if the latter is the case any device or ornament it may bear will be imparted to the edge of the blank.
The coining presses used in various mints may be divided into three types :—(1) the screw press worked by atmospheric pressure, (2) the excentric press, and (3) the lever press. The first of these (see Ency. Brit., 8th ed., vol. vii. p. 92) has now been abandoned. In the excentric press the power is applied to a shaft bearing an excentric which acts by means of a connecting rod upon a verti-cal slide holding the die which is brought down on the blank. This form of press is used in the mint at Constantinople, wdierc the atmo-spheric screw press is also still retained. Of the third type, the lever press, there are two modifications, devised respectively by Thonnelier and by Uhlhorn. The details of theUhlhorn press have been improved by Messrs R. Heaton & Sons of Birmingham ; and, their superiority to the old vacuum screw press having been demon-strated by careful experiments, they have been finally adopted in the newly arranged mint, which contains fourteen of them. This press is shown in figs. 10 and 11. It is driven from below the floor of the press-room by bands which pass over fast and loose pulleys on the same shaft that bears the fly-wheel. The loose pulley, however, is only used when it is necessary to stop the machine entirely, as the fly-wheel is permitted to revolve without imparting motion to the shaft so long as a lever M, worked from the front of the machine, does not cause the fly-wheel to be con-nected with the driving wheel by means of two pins. The dies are placed in the front part of the machine (fig. 10). The lower one is firmly fixed to the bed, while the upper is held at A by the upper of two jaws F and A', or levers, the fulcra of which are so close together as almost to coincide, the lower jaw A' bearing the collar which encircles the blank while it is being converted into a coin ; the upper jaw F, A, governed by the weighted lever H shown below the bed of the machine, has a tendency to rise a sufficient distance to admit the blank between the upper and lower die. A crank B on the shaft bearing the fly-wheel is connected by a rod C with the bent lever D, and this bent lever, acting through the toggle joint and a piece of metal E connected with the jaw that bears the

Fig. 12.
Auto-matic balance.
upper die, forces it down, and thus squeezes the blank between the upper and lower dies. A cam on the crank shaft acting on the lower of the two levers G shown below the bed of the machine causes the lower jaw A' bearing the collar which surrounded the blank to be depressed sufficiently to leave the finished coin freely resting on the lower die, from whence it is driven down the shoot N by the next blank in succession. Coins are produced at rates varying from 60 to 120 a minute, 90 a minute giving the best results. The blanks to be converted into coins are placed on the slide J, and the advance of each blank in succession is regulated by the rod called the " layer on " K, the backward and forward movement of which is also regulated by an excentric on the crank shaft. The details of this part of the machine are shown in plan, fig. 12.
The last operation before the finished coin is returned to the mint office for issue to the public is the weighing each gold or silver piece separately. This is effected in the American and in most Continental mints by hand, but in England automatic balances of beautiful construction are employed. They were originally devised for separating worn pieces from those of current weight, but they are now employed to distinguish between "light," "heavy," and "good" pieces, the latter alone being permitted to pass into circulation. In the newly arranged department thirty such machines are provided. Each is driven from overhead shafting by means of gut lines. The driving pulleys derive their motion from a small atmospheric engine, which is found to give more satisfactory results than would be the case if the steam-engine were employed directly. Each balance is worked by a cone pulley A (fig. 13) by a gut line passing round it from the loose pulleys B, the necessary ten-sion being imparted to the line by means of a spring C. The tension of the line is, however, but slight, for if the action of the balance is arrested by accident the cord slides over the cone pulley A without turning it. It will be obvious that the use of the cone pulley enables the machine to be driven with varying degrees of speed. The toothed wheel D is mounted on the spindle which bears the driving pulley A, but it acts only through the intervention of a friction cheek, which is so lightly screwed against the driving wheel that it would cease to act if the machine should be accidentally deranged. The wheel D sets in motion the wheels E, E', E". The cam F, acting on the curved extremity of the rocking frame G, causes the slide H to bring forward one of a series of coins (arranged in the hopper I) until it rests on the plate J of the balance beam, of which beam a portion is shown in an enlarged drawing above the balance, while the plate that receives the coin is also shown in a separate drawing to the left of the machine. Another cam K then comes into play, and enables the forceps, shown at L, to release the rod M to which the balance plate J is attached. The forceps L serves to keep the rod steady while the coin is being placed on the plate J. A rod shown at 1ST is then raised by the cam O, the lower extremity of the rod being kept steady by a pin sliding in a hole in the bottom plate of the balance, and its upper end by a pin which works into the central support of the balance beam. At the base of this rod N", and at right angles to it, there is a metallic bar QQ, the ends of which pass through stirrups in the pendants M and P from the opposite ends of the beam. The elevation of this horizon-tal rod by the cam O simultaneously releases both ends of the beam, aud the coin placed on the beam plate has then, for the first time, a direct influence on the beam. If the coin is "too light" the counterpoise R in the cage at the end of the rod P will raise the coin, and the revolution of the machine then causes part of the cam K to permit a spring to close the forceps L and to hold the pendant M firm. An indicating finger T then falls, and by means of a horizontal lever UU', which fits into one of three inverted steps on the bottom of the shoot V, determines over which of three orifices W,W,W" in the bottom plate of the balance this shoot shall stand. In the meantime the advance of the slide H brings the next piece forward, aud displaces the coin which has hitherto occupied the beam plate J, forcing the coin down the shoot V, and thence through the orifice W into a receptacle, external to the balance, destined for the reception of "light coin." If this next piece should be "too heavy " it will not only raise the counterpoise B, but will also elevate a little wire S, which would otherwise remain undisturbed on a support. This little wire represents the "working remedy" for the particular denomination of coin in question, which, for safety, is less by Troth of a grain than the remedy permitted by law. The undue weight of the '' heavy coin " will depress the right end of the balance beam and its pendant M to the lowest possible point, and the indicating finger T will, in this ease, determine that the rod UTJ' shall occupy the lowest step of the shoot V, which will conse-quently stand over the orifice W" in the bottom plate of the balance which communicates with the receptacle for the "heavy" coins, and the heavy coin on the beam plate will be driven down the shoot by the next coin in succession. If the coin wdiich is next brought forward by the slide H should be a "good" one, that is, if it is within the working "remedy," its action will be as follows. It may be slightly heavier than the counterpoise, but not sufficiently heavy to lift both the counterpoise and the remedy wire. The balance beam consequently remains approximately horizontal, and the indicating finger T will cause the rod UU' to strike the centre step of the shoot V, which will then stand over the central orifice W in the bed plate wdiich communicates with a receptacle for "good" coins, into which the coin will find its way, as soon as it is driven from the beam plate by the next coin of the series. It will be evident that this excellent appliance both weighs and classifies the coins. About twenty-three coins are passed through it in a minute.
In order to show the importance of extreme accuracy in weighing, it may be pointed out that, although by the Coinage Act of 1870 the "remedy" or allowed variation above or below the standard weight of a sovereign is only ith of a grain, yet in a million sterling of sovereigns the difference between the least and the greatest weight the law allows would be no less than £3244.
The manufacture of coin is not the only work which is performed in the Royal Mint. All medals issued to the army and navy, as well as those given by the Eoyal Society and the university of London and some others, are struck in the mint, and their preparation forms a considerable part of the work of the die department. Since 1874 the clasps and bars for the medals have also been manufactured in the mint, whence they have been issued completely mounted. Another operation, not con-nected with the coinage, which is performed in the mint is the assay of the " diet" or metal scraped from the gold and silver plate manufactured at Sheffield and Birmingham under the direction of the warden of the standard of wrought plate for those towns. By Act of Parliament it is directed that this shall be brought once in each year to the mint to be assayed by the " king's assay master," under the supervision of an officer appointed by the lords of the Treasury.

The gold coin in circulation in Great Britain is esti-mated at £100,000,000. It may be well to add the following table, which gives the value of the gold and silver coinages of four of the most important foreign countries, in two recent years :—

1880. 1881.

Gold. Silver. Gold. Silver.
United States
France £12,461,655 1,332,430 493,605 £5,481,941 1,674,712 £19,370,178 326,837 485,999 83,646 £5,587,840
1,805,734 259,910

£14,287,690 £7,156,653 £20,266,660 £7,653,484
The value of the gold coinage of the American mints
during the fiscal year ending June 1882 amounted to
$89,413,447'50,—being greater than that of any previous
year in their history. (w. c. E.—E. A. H.)

Search the Encyclopedia:

About this EncyclopediaTop ContributorsAll ContributorsToday in History
Terms of UsePrivacyContact Us

© 2005-17 1902 Encyclopedia. All Rights Reserved.

This website is the free online Encyclopedia Britannica (9th Edition and 10th Edition) with added expert translations and commentaries