Then the boats, apparently empty, were rowed back to the pirate ships, and in a short time, again full of men sitting, upright, with their muskets and cutlasses, they went to the shore, and soon afterwards returned apparently empty as before.
This performance was repeated over and over again, until the people in the castle were convinced that Morgan was putting his men on shore in order to make a land attack upon the rear of the castle during the night.

But the Spanish admiral was not to be caught by any such clumsy stratagem as that, and, therefore, in great haste he had his big cannon moved to the land side of the fort, and posted there the greater part of his garrison in order that when the pirates made their assault in the dead of the night they would meet with a reception for which they had not bargained.
When it was dark, and the tide began to run out, the pirate vessels weighed anchor, and they all drifted down toward the castle.

Morgan's spies had perceived some of the extraordinary movements in the Spanish fortifications, and he therefore drifted down with a good deal of confidence, although, had his trick been discovered in time it would have gone very hard with his fleet.

It is probable that he had taken all these chances into consideration and had felt pretty sure that if the cannon of the fort had been opened upon them it would not have been the big ship which carried him and his precious load which would have been sunk by the great guns, and that no matter what happened to the smaller vessels and the men on board them, he and his own ship would be able to sail away.
But the Spaniards did not perceive the approach of the drifting fleet, for they were intrepidly waiting at the back of the castle to make it very hot for the pirates when they should arrive.

Slowly past the great walls of the fort drifted the fleet of buccaneers, and then, at a signal, every vessel hoisted its sails, and, with a good wind, sailed rapidly toward the open sea.