Nick Carter&mdash;known to the captain and crew of the tramp steamer Cherokee as Sykes, the bos&rsquo;n&mdash;heard this shout, taken up by man after man, as he lay stretched out on the foc&rsquo;s&rsquo;le head, in the early morning, just as the ship nosed her way into San Juan harbor, on the northern coast of Porto Rico.<br />The thrilling warning that somebody has fallen into the sea, which always sends a shock through both crew and passengers whenever heard, does not permit any ordinary person to remain quietly dozing.<br />The famous detective was one of the first to rush over to the side of the ship when the alarm had been given.<br />Close by him were his two assistants, Chick and Patsy Garvan, who, in the r&ocirc;les of common sailors, had come down to Porto Rico to help him get back the fortune in jewels which had been stolen from Stephen Reed, the well-known New York millionaire.