Wealth is that which may be used. Value is that by means of which wealth may be exchanged. A currency, therefore, should consist of representatives of value,--of representatives, because value, being ideal, is known only by that means,--of value, because it is only by differences of estimate or value that exchanges are possible. But, as these representatives are wholly nominal, and may, therefore, be issued in any quantity, and as their increase or decrease affects the value of credits, their issue requires regulation. The quantity of the currency may be well regulated by finding the rate per head of population during a favorable state of trade, and by adhering to that invariably. That the people of the United States have reached the degree of science and civilization proper to the creation of such a currency is not yet evident; but there is reason to believe that they will take the lead in this as they have in some other actions indicative of advance,--that they will erelong understand the impropriety of attempting to measure value by means of merchandise, that is, by a means that is subject to variations of quantity,--a conclusion that may not appear obvious in this aspect, but it will be readily understood that in commerce a variable measure is absurd in theory and intolerable in practice. Yet this is precisely parallel with using gold, or any other article of merchandise, as a measure of value. The elements of currency are value, a commercial relation derived from persons, and quantity, a property of things derived heretofore from the precious metals or their representatives. But this quantity is inconstant, and to use an inconstant quantity as a measure, is absurd. The quantity of the currency may, however, be rendered constant, both positively and relatively, by deriving it wholly from persons,--that is, by giving it an invariable quantitative relation to the population: a rule that is both simple and easy of practice, because value is already nominated and numerated, and the population is already sufficiently well known. The divisions of the currency should be the simplest possible, that is, binary, and the definitions of the parts should be as simple as those of coins. With regard to the legal-tender currency, so called, it serves well for temporary use,--much better, indeed, than any of its predecessors; and as long as its promises are ignored, and as long as its quantity is not increased faster than the increase of the population, it is practically a value-currency, resting on its own inherent right of use, with the exception of the limitation defined by the law of legal tender.