The early coins were definite weights of gold, silver or copper, and in many countries coins still bear the names that indicate their original weight. Yet arbitrary rulers have often sought to cheat their subjects by issuing coins of lighter weight and baser metal. The French livre, now the franc, is one seventy-second of its original value. English coins were debased ten times between the years 1299 and 1601 to exactly one-third of their original value. The loss from such debasement falls almost wholly upon the poor, whose wages fail to buy the usual food and clothing. Henry VIII reduced the coins of his realm again and again, until it would have taken five years' revenue of Elizabeth's reign to restore the currency. Elizabeth chose to take the standards as she found them, but to establish an absolute degree of purity and fix by law the weight of each coin in the system. The standard of purity since maintained in England is 22 carats, or eleven-twelfths fine, and weights have been maintained in spite of several efforts to reduce them. Other nations have taken similar steps with varying standards of purity: .835 in the Latin union, .9 in the United States, and over .96 in most coinage of western Asia. In this way the standard of value for every citizen of a country is as clearly defined as the standard of weight, and every transaction in trade, with every account of such transaction, involves that unit.
_United States coinage._--A brief statement of the system of coinage now established in the United States may illustrate the definiteness of the standards of value. The United States mint at Philadelphia and its branches at New Orleans, Denver, San Francisco and Carson have the sole authority for making coins. Any effort at coinage by outside parties is criminal. The mint receives the gold and silver by weight and assay of purity, melts and refines and mixes with alloy, to bring the mass to required fineness, nine-tenths pure, and casts the metal into bars called bullion. These bars are then most carefully assayed, and, if found of exact standard purity, are rolled and drawn into plates the thickness of the coins desired. From these plates disks are punched by machinery, each disk being weighed, and if found too light thrown aside, if too heavy reduced by filing, until every disk represents exactly the required weight of the coin desired. The disks then pass through a milling machine which raises the edges, and when cleaned by dilute acid and carefully dried, are stamped by a steel die with some device covering both surfaces completely. This effectually gives the seal of the nation to the purity and weight of the coin, and, since it covers the whole surface, prevents the possibility of reducing that weight without marring the coin.