The Footprint
I don't know how far anyone else is, so I don't want to comment too far in advance. I have finished the book and you will get to a point where you will not be able to put the book down, you must find out what happens next. At least I did. Then toward the end it slowed back down.
Any comment on the footprint? At first I thought for sure that it was his own footprint, that Robinson had just forgotten that he had been in that area. But then he thinks the same thing and goes back to measure his footprint against the one in the sand. When it doesn't fit, and he finds the sand print to be much larger, he gets more paranoid.
Then there is his constant thought of the cannibals. Are there really cannibals or are they just another figment of his overactive immagination. He does see signs of them coming onto the island, and if they are indeed true cannibals, then he has reason to be afraid. Interesting reading at this point.
Hang in there to completing this book. I'm glad I read it.