Rainsford Falls off of the boat and the waves are extremely dangerous. He's not sure whether he will make it or not.
"Rainsford remembered the shots. They had come from the right, and doggedly he swam in that direction, swimming with slow, deliberate strokes, conserving his strength. For a seemingly endless time he fought the sea. He began to count his strokes; he could do possibly a hundred more and then--"
Rainsford remembered how to swim and made it to the shore.