One day when Robinson was walking along the sand towards his boat, suddenly, close to the water, he stopped as if he had been shot, and, with thumping heart, stood staring in wonder and fear at something that he saw.  The mark of a naked foot on the sand!  It could not be his own, he knew, for the shape was quite different.  Whose could it be?

He listened, he looked about, but nothing could he hear or see.  To the top of a rising ground he ran, and looked all around.  There was nothing to be seen.  And though he searched everywhere on the beach for more footmarks, he found none.

Whose footprint could it be?  That of some man, perhaps, he thought, who might come stealing on him out from the trees, or murder him while he slept.

Back to his house he hurried, all the way in a state of terror, starting every now and again and facing round, thinking he was being followed, and fancying often that a stump or a bush was a man, waiting to spring on him.  That night he slept not at all, and so shaken was his nerve that every cry of a night-bird, even every sound made by an insect or a frog, caused him to start with fear, so that the perspiration ran down his brow.

As day followed day, however, and nothing happened, Robinson began to be less uneasy in his mind, and went about his usual work again.  But he strengthened the fence round his castle, and cut in it seven small loopholes, in which, fixed on frames, he placed loaded muskets, all ready to fire if he should be attacked.  And some distance from the outside of the fence he planted a thick belt of small stakes, so that in a few years’ time a perfect thicket of trees and bushes hid all trace of his dwelling.

Years passed quietly, and nothing further happened to disturb Robinson, or to make him think more of the footprint that had frightened him so much.  But he kept more than formerly to the interior of the island, and lost no chance of looking for good places to hide in, if he should ever need them.  And he always carried a cutlass now, as well as his gun and a couple of pistols.

One day it chanced, however, that he had gone further to the west of the island than he had ever done before, and, looking over the sea, he fancied that he saw, at a great distance, something like a boat or a long canoe, but it was so far off that he he could not be sure what it was.  This made him determine that always in future he would bring with him to his lookout-place the telescope which he had saved from the wreck.

The sight of this supposed boat brought back his uneasiness to some extent, but he went on down to the beach, and there he saw a sight which filled him with horror.  All about the shore were scattered men’s skulls and bones, and bits of burnt flesh, and in one place were the remains of a big fire.  Robinson stood aghast, feeling deadly sick.  It was easy for him to know the meaning of the terrible sight.  It meant that cannibals had been there, killing and eating their prisoners; for when the natives of some parts of the world go to war, and catch any of their enemies, it is their habit to build a fire, then to kill the prisoners and feast on their roasted bodies, eating till they can eat no more.  Sometimes, if the man they are going to eat is too thin, they keep him, and feed him up, till they think he is fat enough.