Discuss Slocum's arrival on the Keeling Cocos Islands. What was Slocum's first sign that he was getting close?

Slocum was eager to reach the Keeling Cocos Islands even though they were 550 miles away. The author felt it was vitally important to be careful so he would not miss the atoll. Slocum's first indicator that he was drawing near was the appearance of a white tern, a bird the islanders refer to as the "Pilot of Keeling Cocos.