Chatham had received very precise instructions from Castlereagh, the objects prescribed to him being, (1) the capture or destruction of the enemy's ships, either building or afloat at Antwerp or Flushing, or afloat in the Scheldt; (2) the destruction of the arsenals and dockyards at Antwerp, Terneuze, and Flushing; (3) the reduction of the island of Walcheren; (4) the rendering of the Scheldt no longer navigable to ships of war. These objects were named, as far as possible, in the order of their importance, and Chatham was specially directed to land troops at Sandvliet and push on straight to Antwerp, with the view of taking it by a _coup de main_. Napoleon, who clearly foretold the catastrophe awaiting the British troops in the malarious swamps of Walcheren, afterwards admitted that Antwerp could have been captured by a sudden assault. Chatham obeyed his general orders, but, instead of taking them in the order of importance, gave precedence to the objects which could most easily be accomplished. By prompt action the French fleet, which was moored off Flushing, might have been captured, but it was allowed to escape to Antwerp. By August 2 the British were in complete possession of the mouth of the Scheldt, and had taken Bath opposite Sandvliet, while Antwerp was still almost unprotected. But Chatham concentrated his attention on the siege of Flushing, which surrendered, after three days' bombardment, on August 16, contrary to Napoleon's expectation. Antwerp had meanwhile been put in a state of defence, and was now protected by the enemy's fleet, while French and Dutch troops were pouring down to the Scheldt. After ten days of inactivity, Chatham advanced his headquarters to Bath, found that further advance was impossible, and recommended the government to recall the expedition, leaving 15,000 men to defend the island of Walcheren. This advice was adopted, but the garrison left in Walcheren suffered most severely from fever in that swampy island. Eventually, on December 24, Walcheren was abandoned, the works and naval basins of Flushing having been previously destroyed. The destruction of Flushing was the sole result of this expedition.