What happened in Chapters 12,13,14,and 15 in The Cay?

After Timothy and Phillip have been on the island about a month, Timothy is stricken with a bout of malaria. Although there is not much he can do, Phillip tries to nurse him through the fever and delirium. Timothy recovers, but "never really regain(s) his strength" (Chapter 12).

Realizing that he might "be poorly again some marnin'", Timothy increases his efforts to help Phillip be able to survive on his own if the need should arise.  He teaches him to fish, and Phillip finds that he is "learning to do things all over again, by touch and feel".  With growing confidence, he volunteers to climb to the top of a coconut tree to fetch some coconuts, something that Timothy cannot do because of his age.  When he succeeds in getting the fruit, Timothy is ecstatic, and Phillip feels that "it (is) almost as if (he'd) graduated from the survival course that Timothy (has) been putting (him) through".  That night, Phillip realizes how much he appreciates Timothy, who seems "only kind and strong" (Chapter 13).

One day in July it is oppressively hot on the island, and the air is eerily still.  A wave cracks upon the rocks like a rifle shot, and Timothy warns that "a veree bad starm is comin'...a tempis'".  The two begin massive preparations for the coming hurricane, lashing their water keg at the top of a palm tree at the highest point on the island, along with a box containing their knife and everything else they have of value. Timothy loops and ties a rope securely around the same tree; in case the freak storm is exceptionally severe, he and Phillip will have to secure themselves to the tree and ride it out (Chapter 14).

The storm hits with heavy rain and crashing surf, and as the winds increase, the hut is blown away.  Timothy and Phillip lie flat on the ground for hours, "taking the storm's punishment", and when the sea begins to reach them, they race for the hilltop and loop their arms into the ropes they have secured to their palm.  Timothy stands behind Phillip, sheltering him with his body, and the two endure the driving wind and rain as the water rises about their feet.  Both of them eventually lose consciousness before the storm's fury, then finally, the tempest abates, and Phillip, reviving, releases himself and Timothy from the ropes.  Timothy's back "has been cut to ribbons by the wind", and Phillip can do nothing but lie beside him, holding his hand.  Before dawn, Timothy dies, and Phillip is left, "blind and alone on a forgotten cay" (Chapter 15).