"I guess we'll change it, and have you and Mark take them," went on the captain. He gave Jack a peculiar look, and made a sign to him not to say anything. Wondering what was to come Jack went up on deck to watch the sunset.
CHAPTER XXI
CAUGHT IN A WHIRLPOOL
The boy was joined a little later by the captain, who, coming close to him whispered:
"I am going to try to discover the ghost to-night. That is why I wanted you boys on hand to help me. This thing must be stopped if it is a joke, and, if it isn't—"
"Do you think it is some one playing tricks?" asked Jack.
"I don't know what to think," answered Mr. Henderson. "We will see what happens to-night."
Mark came on deck a little while, and the three talked of the strange appearances of the mysterious white object. The boys told of their experiences, and Jack related more fully his on the night the ship went up on the big rock upheaval.
"I don't believe in ghosts," said Mr. Henderson, "I'm going to lay this one," and he smiled grimly.