The wind blew strongly, the boat made six or seven knots an hour, and they were rapidly reaching the end of their voyage. As they drew near the island seemed to lift from the sea, and the air was so clear that they could already distinguish the rocks heaped on one another, like cannon balls in an arsenal, with green bushes and trees growing in the crevices. As for the sailors, although they appeared perfectly tranquil, yet it was evident that they were on the alert, and that they carefully watched the glassy surface over which they were sailing, and on which a few fishing-boats, with their white sails, were alone visible.