In England, silver had always been the standard, and by the third year of Elizabeth the coin had been restored to its proper fineness, which thenceforward was scrupulously maintained. But though the metal was not degraded by the government, the stock of bullion, if not constantly replenished from without, tended to diminish in proportion to the growth of the country and the export of specie to Asia. After the discovery of America, the value of silver in relation to gold fell, in Europe, to about fourteen or fifteen to one, while in China or India it stood pretty steady at from ten to twelve to one. Consequently from 1600 downward, silver remained the most profitable cargo which could be sent round the Cape of Good Hope, and, unhappily for British prosperity, at the very moment when the East India Company came into being, piracy ceased. The chief supply of bullion being thus cut off, the strain of the export trade fell upon the coin, and within a little more than a generation the effect become apparent in a degeneration of the currency. To make good her position as a centre of exchanges, England had no choice but to supply her necessities by force. Cromwell understood the situation perfectly, and had hardly assumed the office of Protector when he laid plans to cut the evil at the root by conquering Spanish America, and robbing Spain of her mines. To this end he fitted out his great expedition against Saint Domingo, which was to serve him as his base; but for once his military genius failed him, his commanders blundered, the attack miscarried, and the island of Jamaica was all that came of the campaign.