A week passed by, and we found ourselves perfectly settled in our new home.  Silva was gaining strength and his wounds were healing, and we were all in excellent health.  The doctor also had almost recovered his spirits.  We began now to take a more extended survey of our island.  We calculated that it was from ten to fifteen miles from one end to the other, or rather right across; and as it was nearly circular, with a large lagoon in the centre, we had to walk from thirty to forty miles to go round it.  It was about a mile across in most places.  The beach was formed of broken coral and shells, while the upper portion of the land consisted of the _debris_ of coral, the dung of birds, and vegetable earth.  Out of this composition grew tall cocoa-nut trees, and palms, and pandanus trees, besides a variety of shrubs.