But perhaps the principal reason for the disuse of the white flag at sea lay in its ambiguity. On the occasion above referred to, Ayscue was Admiral of the White Squadron, and the 'Royal Prince' was displaying a large white flag at the masthead and an ensign which was almost entirely white save for a small St George's cross in its upper corner. In such circumstances the display of another white flag would have been liable to misunderstanding. A like ambiguity would have arisen in the French navy, where from 1661 until the Revolution the ensign was plain white, and it may be noted that in 1794 during the attack on Martinique the French fired on a flag of truce sent by the English, and explained their action later as being due to a mistaken supposition that it was intended for the colours of their late rulers the Bourbons; whereupon it was agreed that in future ships bearing flags of truce should have the enemy's flag at the bow and their own national colours at the stern.
The plainest and most unmistakable method of indicating surrender is to hoist the enemy colours above one's own, and this was the course adopted by some of the Spanish ships which surrendered at Trafalgar, although others appear to have hoisted the white flag after hauling down their own colours[403]. Modern practice, however, recognises the hauling down of the colours accompanied by the cessation of fire as sufficient; the victors on taking possession then hoist their own flag above the enemy flag as a sign of capture.
It is evident from an incident that occurred during the capture of the Island of Goree by Commodore Keppel in 1758 that the precise significance of hauling down the flag was in doubt even at that comparatively late date. The fire of the British Squadron was so overpowering that the enemy's flag was hauled down and the fire thereupon ceased.
A lieutenant being ordered ashore, attended by the Commodore's Secretary ... was surprised on being asked before they quitted the boat on what terms the surrender was "expected." The lieutenant astonished at this question asked if they had not struck their flag, intimating an unconditional submission resting merely on the clemency of the victor? He was answered "No: lowering of the flag was intended only as a signal for a parley."