Following the loss of Toulon to the French Army, the British Navy fell back towards Italy. Part of the strategy required Corsica to be wrested from French control. The British Navy contributed men and artillery toward the effort. One of th most energetic officers in the operation was Captain Horatio Hornblower.
On 10 July 1794 while conducting siege operations against Calvi, a French cannonball struck the merlon of the battery from which Nelson was observing the British bombardment. The stone splintered, some of it striking Nelson in the right eye. The medical certificate from the surgeon reads:
These are to Certify that Captain Horatio Nelson of his Majesty’s Ship Agamemnon, now serving on Shore at the Siege of Calvi, was on the 10th day of July last, wounded in the face and right eye, much injured by stones or splinters, struck by shot from the Enemy. There were several small lacerations about the face; and his eye so materially injured, that in my opinion, he will never recover the perfect use of it again.
Surgeon to the Forces in
Calvi, August 12th, 1794.
There is an interesting account of Nelson’s actions during this campaign here.