There was no actual sound to which Tim could attribute his sudden awakening, but he was certain someone was in the control room beside Pat for he could hear the steady breathing of his companion.

Tim forced sleep from his tired brain. He needed every faculty to meet this emergency.

His right hand moved cautiously and his fingers closed around the hard, cold butt of his revolver. There was a slight scraping sound from the dense blackness at the base of the ladder which came down from the main hatch and Tim wished for a flashlight. He didn’t even know where the switch which controlled the interior lights of the S-18 was located.

Only the slightest of shuffling sounds warned Tim that the intruder was coming toward him. Evidently he was in his stocking feet.

Tim managed to free his legs from the folds of his blankets and he crouched on the steel floor of the S-18, ready for whatever might happen.

The hatch which led to the main deck was visible for the sky outside was much lighter than the black interior of the submarine. In this circle Tim saw the head of a man peer into the control room. Unless he did something at once, the S-18 soon might be swarming with unwanted visitors.

Tim heard a slight grunt as the man coming toward him struck his head on the lower end of one of the periscopes. That was all Tim needed. Throwing his strength into the effort, he lunged forward, his outstretched arms enfolding the legs of the intruder. They went down with a crash that brought a muffled cry of alarm from the man Tim had tackled and a real shout of agony from Pat, on whom they had fallen.

“What’s going on here?” cried Pat.

“I don’t know,” gasped Tim, “but someone turned off the light over the hatch and came down here. I just tackled him and there’s another fellow at the hatch about ready to come down.”

The man Tim had tackled recovered suddenly from the surprise attack and struck out with a vigor that caught the flying reporter. A powerful foot struck Tim on the chest and sent him flying across the control room to land on the other side curled against a maze of pipes and valve wheels.

“Have you got him?” cried Pat.

“Not now,” Tim replied. “He kicked me almost through the side of this tin fish. You try and get him.”

“I’ll get him all right,” vowed Pat. “You keep the boy at the hatch from joining him and making this too much of a party.”

Flame lighted the interior of the control room and their eardrums were almost shattered by the deafening roar of a gun discharged at close range. The man Tim had tackled was shooting at the sound of their voices.

“Never mind trying to get this fellow,” called Pat, now safely protected by the bulkhead into the engine room. “We’ll pick him off when he tries to return to the deck.”

The answer to Pat’s words were written in smoke and flame as the unknown intruder fired again.

Tim, watching the outline of the hatch against the sky, saw a head appear. He raised his gun and fired in the general direction of the hatch, more to scare the second man than to actually harm him. On the echo of the crash of his gun came a scream of pain and the head promptly disappeared.

“Good shooting!” cried Pat. “Now we’ll get this fellow. He’s in a cross fire. Next time he shoots let him have it. I’ll see if I can get around to the switch and turn on the lights. This party is going to end all of a sudden.”

Tim strained his senses to detect the spot where the gunman was hidden. He could hear cautious sounds but he didn’t dare fire for fear of hitting Pat. Tim edged near the ladder which led up to the hatch. As he neared it he became conscious of some one crawling up the ladder and he lunged toward the shadowy form.

Just as Tim moved, the man on the ladder lashed out viciously with one foot. The blow caught Tim squarely on the chin and he dropped to the deck, out cold. His gun clattered from his nerveless hands and the man on the ladder leaped for the hatch just as the interior of the S-18 blazed with light.

Pat, momentarily blinded by the glare, recovered in time to see the legs of their assailant disappearing over the edge of the hatch and with snap aim he sent a volley of shots crashing upward.

Feet pounded along the deck of the S-18 and Pat heard the sudden splashing of oars as a small boat pulled away from the hull of the sub in great haste. Pursuit, he knew, was useless and he bent over Tim.

The flying reporter was recovering his senses, but he was still groggy from the sharp blow on his chin. His first thought was one of self defense and he struggled weakly to raise his fists and hammer at Pat.

“Snap out of it,” said Pat, shaking Tim gently. “The show’s all over and we’re still in command of the fort.”

Tim smiled a little sheepishly.

“Someone certainly landed a haymaker on me.”

“You mean a No. 11 shoe connected with your chin at about sixty miles an hour,” chuckled Pat. “A kick like that would have killed anyone but an Irishman.”

Tim shook himself to make sure that he was still all together and got to his feet. He was still a little shaky.

“You stay down here while I go on deck and see what it was all about,” said Pat. He climbed nimbly up the ladder and disappeared just as cries sounded along the dock.

“On board the submarine,” boomed a heavy voice. “What’s the matter down there?”

A beam of light cut through the night and outlined Pat as he stood on the deck.

“Someone tried to board us and we had to call out our own riot squad,” yelled Pat. “Looks like everything is all right now and I don’t think we’ll have any more visitors tonight.”

Satisfied, the watchman returned and Pat called down for Tim to hand up another bulb to replace the one which had been taken from the light over the hatch.

“I’m sure we won’t have any more callers,” he said, “but this light may discourage them even though it didn’t the first time. How in the dickens did you happen to wake up?”

“You might call it my ‘news sense’ being on the job,” said Tim as he rubbed his bruised chin. “The first thing I sensed was that the light was out. Then I knew someone was moving around in the control room and after that I was almost too scared to move.”

“Seems to me you did a pretty nice job of tackling, but the next time don’t bring your man down on top of me. It’s an awful shock to awake in the middle of the night and find a first class fight taking place right in your midships.”

Tim glanced at his wrist watch.

“It’s one a.m.,” he said. “What’s on the schedule now?”

“We might as well try and get a little more sleep. I think the fireworks are over for tonight.”

Pat rolled back into his blankets and a minute later Tim followed his companion’s action but where Pat was soon in a deep sleep, Tim remained awake, thinking over the attack and the dangers of their long voyage into the Caribbean. He was glad Commander Ford had decided to take a seaplane on the trip. It made him feel more comfortable for if anything happened to the S-18 on the treasure hunt, they might be able to get word of their plight to the world by using the seaplane.

Tim finally slept and when he awoke, sunlight was streaming down through the hatch and Commander Ford was climbing aboard.

“Fine pair of watchmen I left,” he smiled.

“You left one mighty alert one,” put in Pat, and he recounted their experiences of the night.

“Sladek is certainly losing no time in trying to hamper my plans,” said Ford. “I imagine he’ll attempt to trail us all of the way to the island but we may fool him if we decide to travel underwater for a few miles.”

“But you couldn’t do that with the plane on deck,” protested Tim.

“We might release the plane and have you fly on ahead, meeting us at the rendezvous on the island,” suggested Ford.

If Tim thought his days on the News had been busy, they were nothing compared with the bustle of activity which settled down on the S-18. For his own part, he was busy testing the seaplanes at the Sea King factory and he finally selected the craft which the sales manager had recommended. It was a three passenger job, light but sturdy and exceptionally easy to handle.

For the next week Tim went to the airplane plant daily to take special instructions in the handling of the plane and to learn the trick of getting off choppy water for there was no telling in what kind of weather he might be called upon to make a flight.

The fuel tanks were enlarged to give the speedy craft a cruising radius of a thousand miles and the pontoons were especially reinforced for the rough work which Tim and his plane might encounter.

By the end of the week great changes had been effected in the hull of the S-18. Steel workers had cut out the special diving chamber in the forward torpedo room, the galley had been installed in the rear compartment which was the crew’s quarters, a special radio set capable of communicating instantly with the New York Journal office was in place, and many other minor alterations necessary for the cruise had been made. The crew was being increased daily, but it was not until the first mess was served on board that Tim had a chance to see them together. In all, sixteen men were to make the trip into the Caribbean and Tim looked at them with interest as they sat around the table for the evening meal.

At the head of the table was Commander Ford and at the other end Pat Reynolds. Tim sat at Pat’s right. Ranged up and down each side were the other thirteen, George Gadd, the engineer, Fred Hanson, the chief electrician, Joe Gartner, old navy torpedoman and gunner, Charlie Gill and Russ Graham, deep sea divers, and their assistants, Earl Bell and Roy Gould.

Ike Green was the radio operator while Forman Gay, Erich Gaunt, Sam Schneider, Al Hardy and Tom Grandrath were former submarine men who would assist in the general operation of the submarine. With the exception of Pat, Tim and Ike Green, the radioman, and the divers, all of the others had served with Ford during the war. The divers and their assistants were old navy men who could be relied upon and Tim knew that Commander Ford was taking every precaution against any treachery among members of his own crew.

It was a clean, hard-bitten crew that could be depended upon in any emergency.

The Commander, Ford was discussing final plans.

“We’re going down the sound for a trial run tomorrow morning. If everything goes well, we’ll start south the day after tomorrow.”

Early the next morning lines were cast off and the S-18, pulsating to the clicking of her powerful Diesels, was backed slowly away from the shipyard. A tug stood by to give any assistance needed, but the S-18 cleared the yard and nosed slowly down river. Overhead a seaplane wheeled.

Tim was in the conning tower with Commander Ford and he pointed upward.

“That must be Sladek’s plane, keeping track of us,” nodded Ford. “I understand his ship is ready to go at a moment’s notice. He’s gathered a crew of thirty of the toughest characters on the waterfront and promised them all a good slice of the bullion if he gets it. Knowing Sladek as I do, I wouldn’t put much faith in his word if I were a member of that crew.”

When the S-18 was clear of the lower bay, the warning bell sounded and everyone on deck went below. Hatches were made fast and every member of the crew went to his station. For Tim there was nothing to do but stand in the control room and watch the activities of the others for he was not experienced enough in submarine operation to be placed at one of the important posts.

Commander Ford’s commands were crisp and alert. The Diesels were silent and only the faint humming of the big electric motors could be heard. Then the S-18 moved on a slight angle and Tim knew they were going below. He had encountered a good many queer sensations in an airplane, but none quite so alarming as the one which gripped him now. He was actually going under the surface with only the thin steel walls of the submarine to ward off the destructive force of the water.

Tim glanced around the control room. Commander Ford was standing with his eyes glued to the periscope. Pat was at the main diving rudders. Forman Gay and Erich Gaunt were at the valves which controlled the ballast tanks. All were silent, intent on their work.

“Are the forward ballast tanks flooded?” snapped the commander.

“Yes sir,” replied Pat.

“How about the after tanks?”

“They’re flooded.”

“Then level off and hold her at forty feet.”

The submarine resumed her even keel, but Tim knew they were forty feet below the surface.

Commander Ford left his post and visited each compartment, making sure that everything was functioning smoothly. When he returned, he said calmly: “We’ll go a little deeper.”

The diving rudders were inclined again and the S-18 nosed its way deeper into the water.

Tim watched the depth gauge, fascinated. The needle was marking the distance steadily. Sixty, seventy, eighty feet they went. Now they were moving downward again. Ninety, ninety-five and then a hundred.

George Gadd, the engineer, came into the control room.

“Everything’s all right so far,” he reported.

“Then we’ll go the rest of the way,” decided Commander Ford.

Tim knew what the order meant. They were going to the bottom, going down to make absolutely sure that the S-18 was ready for the Caribbean treasure hunt.