The experience of the United States with a double standard, extending as it does from 1792 to 1873 without a break, and from 1878 to the present time, is a most valuable source of instruction in regard to the practical working of bimetallism. While we have nominally had a double standard, in reality we have either had one alone, or been in a transition from one to the other standard; and the history of our coinage strikingly illustrates the truth that the natural values of the two metals, in spite of all legislation, so vary relatively to each other that a constant ratio can not be maintained for any length of time; and that “the poor money drives out the good,” according to Gresham’s statement. For clearness, the period may be divided, in accordance with the changes of legislation, into four divisions: I. 1792-1834. Transition from gold to silver. II. 1834-1853. Transition from silver to gold. III. 1853-1878. Single gold currency (except 1862-1879, the paper period). IV. 1878-1884. Transition from gold to silver. I. With the establishment of the mint, Hamilton agreed upon the use of both gold and silver in our money, at a ratio of 15 to 1: that is, that the amount of pure silver in a dollar should be fifteen times the weight of gold in a dollar. So, while the various Spanish dollars then in circulation in the United States seemed to contain on the average about 371-¼ grains of pure silver, and since Hamilton believed the relative market value of gold and silver to be about 1 to 15, he put 1/15 of 371-¼ grains, or 24-¾ grains of pure gold, into the gold dollar. It was the best possible example of the bimetallic system to be found, and the mint ratio was intended to conform to the market ratio. If this conformity could have been maintained, there would have been no disturbance. But a cause was already in operation affecting the supply of one of the metals—silver—wholly independent of legislation, and without correspondingly affecting gold.