John Locke, "Short Observations On a Printed Paper, Entitled, For Encouraging the Coining Silver Money In England, and After For Keeping It Here" in The Works of John Locke in Nine Volumes, Vol 4 (London: Rivington, 1824).

Excerpt:

The matter in short is this; England sending more consumable commodities to Spain than it receives from thence, the merchants, who manage their trade, bring back the overplus in bullion, which, at their return, they sell as a commodity. The chapmen, that give highest for this, are, as in all cases of buying and selling, those who can make most profit by it; and those are the returners of our money, by exchange, into those countries, where our debts, any way contracted, make a need of it: for they getting 6, 8, 10, &c. per cent. according to the want and demand of money from England there, and according to the risque of the sea, buy up this bullion, as soon as it comes in, to send it to their correspondents in those parts, to make good their credit for the bills they have drawn on them, and so can give more for it than the mint-rate, i. e. more than equal weight of milled money for an equal weight of standard bullion; they being able to make more profit of it by returns.

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