The Grampus was in those waters for a purpose; and the only way to discover what that mission was, was by keeping track of Jurgens and his men.
[CHAPTER XIII.]
A MOVE AND A COUNTERMOVE.
"When did you first see the Grampus, Dick?" asked Matt, still watching for some sign of life about the submarine.
"She came up about a minute before I called you," replied Dick. "I awoke, saw the sun shining, and stepped out of the tent. About the first thing my eyes rested on, when they turned toward the cove, was that red ball on top of the staff. The submarine wasn't in sight, but that red ball was just awash and moving toward the shore. I hadn't a notion what it could be, and as I stood and looked the ball rose out of the water. Then the Grampus shoved her wet deck into sight, and I made a jump for the tent to get you."
The red ball to which Dick referred was fastened to the end of a staff that was planted in the submarine's deck. Matt was equally at a loss to understand what use the ball could possibly serve.
"Meppy," said Carl, who was always ready with a theory of his own, "der pall is to schare avay der sharks. But for vy has der Grambus come here ven she iss due at Durtle Islandt? Has somet'ing gone wrong mit Jurgens' galguladions?"
At that moment the top of the conning tower was pushed upward, and the head of Jurgens appeared over the rim. The head rose until Jurgens was half out of the tower. The boys could see that he was curious about the tent under the palm trees. He would lift his eyes to the fluttering white flag, and then he would drop them to the tent. Finally Jurgens got out on the submarine's deck.
"Whistler!" the boys heard him call.