Two sturdy boats, both collapsible, were brought up from the diving compartment and assembled on the deck. Charlie Gill and Russ Graham, the chief divers, checked over their equipment and Pat gave Tim a hand in loosening the fastenings which held the seaplane to the deck. Joe Gartner even found time to polish his beloved four inch gun and Tim felt that Joe was secretly praying for a chance to get into action against the _Iron Mate_. When the first boat was lowered into the water, Commander Ford stepped into the stern and Charlie Gill and Russ Graham manned the oars. The commander was going to waste no time in attempting to locate the wreck of the treasure ship. The crew of the _S-18_, clustered on deck, watched the progress of the small boat as it bobbed about inside the reefs. Both Gill and Commander Ford were busy making soundings while the other diver handled the boat. Back and forth they crept along the reef, their lines dragging the bottom for some sign of the Southern Queen. The hours slipped away and the other boat, in charge of Pat, joined the first in the quest for the location of the old vessel. Tim remained on deck, squatting in the shadow of the seaplane. Ike Green joined him. "Why don't they take the _S-18_ down and creep along the bottom until they find the Southern Queen?" asked Tim. "Commander Ford's afraid of the currents around the reef. He wants to know something about the bottom before he takes the _S-18_ down." The remainder of the afternoon was spent with the two small boats dragging their grappling hooks along the bottom. At sundown the weary crews returned to the submarine. There was no use to ask whether they had found any trace of the Southern Queen. The tired, disappointed faces were enough. "What about the bottom?" Tim asked Pat. "It's going to be a tough proposition even if we find the old ship. Lots of rock down there and queer currents. There must be all kinds of holes in the outer reef." Commander Ford was silent, planning the activities for the next day, and everyone aboard the submarine, except the watch, was in their blankets early. The next morning at dawn the men of the _S-18_ were on deck, preparing for another day of grappling for the wreckage of the Southern Queen. "I wonder if Crazy John could have been mistaken?" Tim asked Pat. "It's possible, but I don't believe Commander Ford would have fitted out an expensive expedition like this if he hadn't been pretty sure of his facts. We've got a lot of territory inside the reefs to explore before we give up hope." "Or before Sladek and the _Iron Mate_ arrive," put in Tim, searching the sky for a possible trace of the seaplane from the tramp steamer.