How does Stevenson foreshadow yet another danger for Jim?

In Chapter 25, Jim finds the deck of the ship empty foreshadowing something has happened on the ship. Namely, the two watchmen are dead and Jim takes control of the ship.

Foreshadowing means ro give a warning or predict of a future event. At many stages, Stevenson has use this technique to give readers a hint that what will happen next and bring some suspense, and in chapter 25 he has used the same technique. In chapter 25, Jim finds the deck empty foreshadowing something had happened, and later he came to know about it because, that red cap man was dead in a fight with Israel Hands who himself was badly wounded.