Orders had been issued before he left that the oars of the boats were to be muffled, that the chains at the entrance of the channel were to be removed, and the ships got in a position, with shortened cables, for a start.

He could picture to himself, as he stood there gazing into the darkness, that the men would be already in the boats awaiting his signal, and as soon as it was seen they would begin to tow the vessels out of the harbor.
During the daytime the frigate cruised backward and forward under easy sail some two miles off the entrance; but the sailors believed that at night she came very much closer to the shore, the lookout with night-glasses having reported that she had been seen once or twice within a quarter of a mile of the entrance to the channel.
Half an hour passed without any sign that the frigate was aware that the ships were leaving the harbor; then Ralph heard the sound of a distant musket-shot, followed by several others, and had no doubt that one of the frigate's boats on watch near the channel had discovered them.
A few minutes later there was a flash some distance out at sea, followed after an interval by the deep boom of a gun; then came a broadside, followed by a steady fire of heavy guns.

These were evidently fired on board the frigate, no answering sounds from the French ships meeting his ear.

He could see by the direction of the flashes that the frigate was under way.

The firing continued for two hours, becoming more and more distant, and then it ceased altogether.
When the sun rose he saw the frigate some twenty miles away.