I had but just turned my back upon it and left it empty, and my wonder may be fancied when I saw a boat and several men in that deserted spot.

The boat was lying by the rocks.

A pair of fellows, bareheaded, with their sleeves rolled up, and one with a boathook, kept her with difficulty to her moorings for the current was growing brisker every moment.

A little way off upon the ledge two men in black clothes, whom I judged to be superior in rank, laid their heads together over some task which at first I did not understand, but a second after I had made it out--they were taking bearings with the compass; and just then I saw one of them unroll a sheet of paper and lay his finger down, as though identifying features in a map.

Meanwhile a third was walking to and fro, polling among the rocks and peering over the edge into the water.