In the spring of 1587 Drake, with six vessels belonging to the crown and twenty-four equipped by merchants of London and other places, had seized a moment when Elizabeth's fickle mind had inclined to warlike measures, and knowing that the mood might last but a day, had slipped out of Plymouth and sailed for Spain a few hours before a messenger arrived with a peremptory order from Elizabeth against entering any Spanish port or offering violence to any Spanish town or ships. Although caught in a gale in the Channel, Drake held on, and, reaching Gibraltar on the 16th April, ascertained that Cadiz was crowded with transports and store ships. Vice Admiral Burroughs, controller of the navy, who had been specially appointed to thwart Drake's plans, opposed any action being taken; but Drake insisted upon attack, and on the 19th the fleet stood in to Cadiz harbour. Passing through the fire of the batteries, they sank the only great ship of war in the roads, drove off the Spanish galleys, and seized the vast fleet of store ships loaded with wine, corn, and provisions of all sorts for the use of the Armada. Everything of value that could be conveniently moved was transferred to the English ships, then the Spanish vessels were set on fire, their cables cut, and were left to drift in an entangled mass of flame. Drake took a number of prisoners, and sent a messenger on shore proposing to exchange them for such English seamen as were prisoners in Spain. The reply was there were no English prisoners in Spain; and as this notoriously untrue, it was agreed in the fleet that all the Spaniards they might take in the future should be sold to the Moors, and the money reserved for the redeeming of such Englishmen as might be in captivity there or elsewhere.