Page:Treatise on Currency and Banking.djvu/23



, and other elementary writers on the science of Political Economy, have shown the principles upon which commodities must have been exhanged in that rude condition of society which preceded the use of metallic money, and it is not my intention to travel over the same ground, and occupy the attention of the reader in recapitulating details with which he is probably already familiar. Nor is it my intention to give a history of the various inventions to facilitate barter, which have been adopted at various periods in different countries, such as the use of cattle, cowry shells, tobacco, iron, and some other objects, each of which has been at some period employed to perform the function of what has been appropriately denominated "a medial commodity," by which the relative value of other things could be determined. I propose at once to enter upon the subject of currency as we find it at the present day in commercial nations, and shall first point out the laws by 1