Calder's action
Nelson's message about the returning French fleet reached Lord Barham at the Admiralty on 8 July 1805. This gave him ample time to reposition his ships.
On 22 July, a detachment of the Channel Fleet under Sir Robert Calder engaged Villeneuve off Cape Finisterre.
Fought in fog and with little wind, the action was indecisive. Although outnumbered, Calder took two Spanish vessels before nightfall, but he failed to re-engage the next morning. The Franco-Spanish fleet managed to retreat, leaving French plans for an invasion of Britain in disarray.
Meanwhile, Napoleon learned that the Austrians had begun to mobilize their army. On 27 August, he ordered his troops to leave Boulogne and march south-east to attack Austria.
Though many of Calder's naval colleagues sympathised at the time, the public – now used to Nelson's overwhelming victories – criticised his failure to pursue the enemy. He was later severely reprimanded by the Admiralty. With hindsight, however, Calder played a key role in upsetting Napoleon's grand invasion plans.