The boy must have had a premonition, he thought, that something was going to happen to him.

Only two theories remained.

One was that Joe had gone crazy under his long exile from civilized life and had madly put an end to himself by jumping into the river; and the other that, persisting in his belief in the instability of the drift-pile, he had gone to the upper bank for safety and had fallen asleep there.

In that event he must be found, lest an Indian should discover him in the morning and put him to death.

Tom went ashore after explaining his purpose to Judie, so that she might not be alarmed at his absence, and literally spent the entire night in hunting for the black boy.