They want to throw the officers off their guard.

It's a pity you have been seen talking so much to me, because, of course, they won't say anything when you are listening; but one or two of the men who came into the regiment with me have dropped a word as they happened to pass this morning that they wanted to have a word if they could get one without being noticed, so I hope to hear a little more tonight." That evening, before going below, Jack had an hour's talk with Sergeant Edwards.
"It's just as I thought," the latter said, "they've got an idea of seizing the ship.

The men I spoke of managed to get a few words with me this evening.

They don't know anything about piracy.

All they have heard is that there is a proposal to seize the ship and to carry her into one of the northern ports of Spain, where the men will land and give up their arms to the Spanish authorities, and then either disperse and make their way home by twos and threes as best they can, or they will take service with the King of Spain, who, they think, will pay them a deal better than the English government.
"A part of the crew are in the scheme.