Having attained flag rank on 24 September 1787, Duncan became
vice admiral 1 February 1793, and was promoted to
admiral 1 June 1795. In February 1795, he was appointed
Commander-in-Chief, North Sea, and hoisted his flag on board . During the first two years of Duncan's command, the work was limited to enforcing a rigid blockade of the enemy's coast, but in the spring of 1797, it became more important from the knowledge that the
Batavian Navy fleet in the
Texel was getting ready for sea. The situation was one of extreme difficulty, for
the mutiny which had paralysed the fleet at the
Nore broke out also amongst the crews under Duncan, and kept him for some weeks in enforced inactivity. Duncan's personal influence and some happy displays of his vast personal strength held the crew of
Venerable to their duty; but with one other exception, that of , the ships refused to quit their anchorage at
Yarmouth, leaving
Venerable and
Adamant alone to keep up the pretence of the blockade. Fortunately, the Batavian navy was not at the time ready for sea; and when they were ready and anxious to sail, with 30,000 troops, for a planned invasion of
Ireland, a persistent westerly wind detained them in harbour until they judged that the season was too far advanced. For political purposes, however, the Batavian government ordered the Texel fleet's commander, Admiral
Jan Willem de Winter to put to sea in the early days of October despite de Winter's reservations. Duncan, with the main body of the fleet, was at the time lying at
Great Yarmouth revictualling, the Texel being watched by a small squadron under Captain
Henry Trollope in , from whom he received early information of the Batavian navy being at sea. He at once weighed anchor, and with a fair wind approached the Dutch coast, saw that de Winter's fleet was not returned to the Texel, and steering towards the south sighted it on the morning of 11 October about seven miles from the shore and nearly halfway between the villages of
Egmont and
Camperdown. The wind was blowing straight on shore, and though the Batavian fleet formed their line to the north and preserved a bold front, it was clear that if the attack was not made promptly they would speedily get into shoal water, where no attack would be possible. Duncan at once realised the necessity of cutting off their retreat by getting between them and the land. At first, he was anxious to bring up his fleet in a compact body, for his numbers were at best equal to those of de Winter's; but seeing the absolute necessity of immediate action, without waiting for the ships astern to come up, without waiting to form line of battle, and with the fleet in very irregular order of sailing, in two groups, led respectively by himself in
Venerable and Vice-admiral
Richard Onslow in
Monarch, he made the signal to pass through the enemy's line and engage to leeward. It was a departure from the rule laid down in the
Fighting Instructions, still new, though warranted by the more formal example of
Howe on
1 June 1794; and on this occasion, as on the former, it was crowned with success. The engagement was long and bloody; for though Duncan, by passing through the enemy's line, had prevented their retreat, he had not advanced further in tactical science, and the battle was fought out on the principles of ship against ship, the advantage remaining with those who were the better trained to the great gun exercise, though the Batavian fleet inflicted great loss on the Royal Navy. It had been proposed to de Winter to make up for the want of skill by firing shell from the lower deck guns, and some experiments had been made during the summer which showed that the idea was feasible. However, want of familiarity with an arm so new and so dangerous presumably prevented its being acted on in the battle. ==Rewards==