Principles of Political Economy · John Stuart Mill
Chapter XVI. Of The Foreign Exchanges.
It thus appears that a depreciation of the currency does not affect the foreign trade of the country: this is carried on precisely as if the currency maintained its value. But, though the trade is not affected, the exchanges are. When the imports and exports are in equilibrium, the exchange, in a metallic currency, would be at par; a bill on England for the equivalent of $25 would be worth $25. But $25, or the quantity of gold contained in them, having come to be worth in the United States $30, it follows that a bill on England for $25 will be worth $30. When, therefore, the _real_ exchange is at par, there will be a _nominal_ exchange against the country of as much per cent as the amount of the depreciation. If the currency is depreciated 10, 15, or 20 per cent, then in whatever way the real exchange, arising from the variations of international debts and credits, may vary, the quoted exchange will always differ 10, 15, or 20 per cent from it.
However high this nominal premium may be, it has no tendency to send gold out of the country for the purpose of drawing a bill against it and profiting by the premium; because the gold so sent must be procured, not from the banks and at par, as in the case of a convertible currency, but in the market, at an advance of price equal to the premium. In such cases, instead of saying that the exchange is unfavorable, it would be a more correct representation to say that the par has altered, since there is now required a larger quantity of American currency to be equivalent to the same quantity of foreign. The exchanges, however, continue to be computed according to the metallic par. The quoted exchanges, therefore, when there is a depreciated currency, are compounded of two elements or factors: (1) the real exchange, which follows the variations of international payments, and (2) the nominal exchange, which varies with the depreciation of the currency, but which, while there is any depreciation at all, must always be unfavorable. Since the amount of depreciation is exactly measured by the degree in which the market price of bullion exceeds the mint valuation, we have a sure criterion to determine what portion of the quoted exchange, being referable to depreciation, may be struck off as nominal, the result so corrected expressing the real exchange.
The same disturbance of the exchanges and of international trade which is produced by an increased issue of convertible bank-notes is in like manner produced by those extensions of credit which, as was so fully shown in a preceding chapter, have the same effect on prices as an increase of the currency. Whenever circumstances have given such an impulse to the spirit of speculation as to occasion a great increase of purchases on credit, money prices rise, just as much as they would have risen if each person who so buys on credit had bought with money. All the effects, therefore, must be similar. As a consequence of high prices, exportation is checked and importation stimulated; though in fact the increase of importation seldom waits for the rise of prices which is the consequence of speculation, inasmuch as some of the great articles of import are usually among the things in which speculative overtrading first shows itself. There is, therefore, in such periods, usually a great excess of imports over exports; and, when the time comes at which these must be paid for, the exchanges become unfavorable and gold flows out of the country. This efflux of gold takes effect on prices [by withdrawing gold from the reserves of the banks, and so by stopping loans and the use of credit, or purchasing power]: its effect is to make them recoil downward. The recoil once begun, generally becomes a total rout, and the unusual extension of credit is rapidly exchanged for an unusual contraction of it. Accordingly, when credit has been imprudently stretched, and the speculative spirit carried to excess, the turn of the exchanges and consequent pressure on the banks to obtain gold for exportation are generally the proximate cause of the catastrophe.
A glance at Chart No. XIII will give illustration to the situation here described. After the war, and until 1873, while the United States was under the influence of high prices and a speculation which has been seldom equaled in our history, the resulting great excess of imports became very striking. It was an unhealthy and abnormal condition of trade. The sudden reversal of the trade by the crisis in 1873 is equally striking, and, as prices fell, exports began to increase. The effect on international trade of a collapse of credit is thus clearly marked by the lines on the chart.
Text from Project Gutenberg, public domain in the United States.