the same just amount of purchasing power which he parted with in 1870. Now, if, in 1880, when his note falls due, the government list is examined, and it is found that commodities in general have fallen in value relatively to gold, the multiple unit will not amount to as much gold as it did in 1870; perhaps each unit may be rated only at $100. In that case, A is obliged to pay back but eight multiple units, which costs him only $800 in money, while B receives from A the same amount of purchasing power over other commodities which he loaned to him. B had no just claim to ten units, since the fall of all commodities relatively to gold was not due to his exertions. On the other hand, if, between 1870 and 1880, prices had risen, mutatis mutandis, the eight units would have cost A more than $1,000 in gold; but he would have been justly obliged to return the same amount of purchasing power to B which he received from him.
§ 2. Gold and Silver, why fitted for those purposes.
By a tacit concurrence, almost all nations, at a very early period, fixed upon certain metals, and especially gold and silver, to serve this purpose. No other substances unite the necessary qualities in so great a degree, with so many subordinate advantages. These were the things which it most pleased every one to possess, and which there was most certainty of finding others willing to receive in exchange for any kind of produce. They were among the most imperishable of all substances. They were also portable, and, containing great value in small bulk, were easily hid; a consideration of much importance in an age of insecurity. Jewels are inferior to gold and silver in the quality of divisibility; and are of very various qualities, not to be accurately discriminated without great trouble. Gold and silver are eminently divisible, and, when pure, always of the same quality; and their purity may be ascertained and certified by a