The commander of the treasure hunting expedition departed and left Tim in the tail of the sub with Pat Reynolds. "This is the last compartment," explained Pat, pointing to the bunks which ranged along the walls. "We'll be carrying a small crew so this is where we'll be living for the next couple of months. There's another compartment for crew's quarters up ahead but we'll probably use that to store diving apparatus and to pack it full of stores and other equipment we'll be needing." Tim was looking at the rear bulkhead and Pat followed with his eyes. "That's the aft torpedo tube," he said, pointing to the heavy steel breech through which the tube was loaded. "The torpedo rack is just to the right but I don't imagine we'll be carrying any torpedoes with us this trip." "I thought it was impossible to get them for private use." "It's supposed to be, but Ford has ways of getting things he wants. He was one of the navy's ace undersea commanders during the World War and the department hasn't forgotten his fine work. There's such a thing as loaning a torpedo for experimental work. Of course it is just possible that the torpedo might be lost during the experiments." Pat grinned broadly. "Is that the same reason this sub has been left so completely equipped, even to the four-inch gun?" Pat nodded. "That's one of them. Another is an unhealthy dislike of Uncle Sam for our friend Sladek. Federal officers have been after him for months but so far they haven't been able to get anything on him that would warrant a trial. None of them would be sorry if Sladek just didn't return from the Caribbean." CHAPTER FIFTEEN An Unknown Intruder Pat started forward and Tim followed him through the motor room, the engine room back into the control room, and then into the forward compartments. Just ahead of the control room was a small cubby with a maze of electrical devices. "You might call this the eyes and ears of the sub," said Pat. "Here are the listening devices by which we can ascertain how far away a ship is, and the radio equipment. This is a special compartment built for just this type of submarine." "Don't the newer ones have it?" asked Tim. "Yes. Even more elaborate than ours and the equipment in them is located in the main control room." Ahead of the radio room was a white-walled compartment which had been stripped of its former equipment. "This used to be crew's quarters, but when Ford got an option on the _S-18_, the bunks and lockers were taken out. Our diving equipment and stores will be kept here." They went on, ducking their heads to enter the forward torpedo room. In the bulkhead Tim saw the breeches of four powerful tubes. The cranes which lifted the torpedoes from the racks and into the tubes were folded back against the wall but the front end of the compartment was a maze of gauges and valve wheels.