l just show her the fastest pair of heels in the
West Indies."

He did not speak again for a full quarter of an hour, but he used the
glasses often, always looking at the same spot on the western horizon.
Robert was at last able to see a black dot there with his unassisted
eyes, and he knew that it must be a ship.

"She's going almost due south," said the captain, "and in two hours we
should overhaul her."

"Why do you wish to overhaul her?" asked Robert.

"She may be a privateer, a Frenchman, or even a pirate, and if so we
must give the alarm to other peaceful craft like ourselves in these
waters."

He raised the glasses again and did not take them down for a full five
minutes. Meantime the strange ship came nearer. It was evident to Robert
that the two vessels were going down the sides of a triangle, and if
each continued on its course they would meet at the point.

The night was steadily growing brighter. The moon was at its fullest,
and troops of new stars were coming out. Robert saw almost as well as by
day. He was soon able to distinguish the masts and sails of the
stranger, and to turn what had been a black blur into the shape and
parts of a ship. He was able, too, to tell that the stranger was keeping
steadily on her course, but the schooner, obeying her tiller, was
drawing toward her more and more.

"They don't appear to be interested in us," he said to the captain.

"No," replied the man, "but they should be. They show a lack of that
curiosity which I told you is necessary at sea, and it is my duty to
overtake them and tell them so. We must not have any incautious ships
sailing in these strange waters."

Ten minutes later he called the mate and gave a command. Cutlasses and
muskets with powder and ball were put at convenient points. Every man
carried at least one pistol and a dirk in his belt. The captain himself
took two pistols and a cutlass.

"Merely a wise precaution, Peter," he said, "in case our peaceful
neighbor, to whom we wish to give a useful warning, should turn out to
be a pirate."

Robert in the moonlight saw his eyes gleam and his lips curve once more
into a smile. He had seen enough of men in crucial moments to know that
the slaver was happy, that he was rejoicing in some great triumph that
he expected to achieve. In spite of himself he shivered and looked at
the stranger. The tracery of masts and spars was growing clearer and the
dim figures of men were visible on her decks.

"O