HMS Merlin was an 8-gun yacht of the Royal Navy. In 1671 she played an important role in provoking the Third Anglo-Dutch War. While carrying the wife of the British ambassador Sir William Temple, Dorothy Osborne, through the Dutch fleet anchored near Den Briel, the Dutch warships fired 'white smoke' as a salute, as was mandatory under treaty, but did not lower their flags. The 8-gun royal yacht started firing live rounds.
The Dutch commander Van Ghent, who knew both Sir William and his wife very well, had himself rowed over to the small vessel to enquire what the problem was. The answer was that the yacht expected to be greeted as a full warship, as a 1662 treaty prescribed. Van Ghent answered that he was doubtful as to whether the Merlin was in that category and did not want to create a precedent.
Charles now ordered the intriguer George Downing, the new ambassador in The Hague, to demand that the admiral would be severely punished, which the States-General of the Netherlands refused.
The yacht Merlin is again noted as the vessel that Captain Greenville Collins commanded in the seven years between 1681 and 1693 when he created a complete survey of the coastline of the British coast. The work was published by Freeman Collins and sold by Richard Mount of London as the Great Britain's Coasting Pilot'. It may have been based to some extent on Dutch maps but the speed and breadth of the work was identified as a laudable act of hydrography.