TOM SWIFT AND THE ELECTRONIC HYDROLUNG
THE NEW TOM SWIFT JR. ADVENTURES
TOM SWIFT AND THE ELECTRONIC HYDROLUNG
BY VICTOR APPLETON II
ILLUSTRATED BY CHARLES BREY
NEW YORK GROSSET & DUNLAP PUBLISHERS
Copyright BY GROSSET & DUNLAP, INC., 1961
[Transcriber's note: Extensive research did not uncover any evidence that the copyright on this publication was renewed.]
ALL RIGHTS RESERVED
PRINTED IN THE UNITED STATES OF AMERICA
1 PIRATE MISSILE 11 2 UNDERSEA SURVEY 20 3 INVISIBLE SUB 31 4 AERIAL ATTACK 39 5 A HUNCH PAYS OFF 50 6 THE CAISSON CLUE 56 7 PORPOISE TAG 64 8 DATE TROUBLE 72 9 A MAGNETIC KIDNAPING 81 10 TELEPHONE CODE 90 11 SQUARE-DANCE HOAX 100 12 DETECTION TEST 109 13 ENEMY FROGMEN 119 14 A PROPAGANDA BLITZ 130 15 MOUNTAIN HIKE 140 16 THE GUNMAN'S SURPRISE 148 17 A MISSING AMULET 156 18 SMILEY THE SEA COW 166 19 FLASH FROM THE DEPTHS 176 20 A LUCKY BLAST 183
Tense, excited men gazed spaceward from the ships and planes of the South Atlantic task force. Other watchers waited breathlessly in the control room of the ship Recoverer. Among these was Tom Swift Jr.
"How close to earth is our Jupiter probe missile?" Bud Barclay asked Tom excitedly.
The lanky blond youth beside him, in T shirt and slacks, shot a glance at the dials of the tracking equipment. "Eight thousand miles from this spot, Bud. It should land here in fifteen minutes!"
Tom Jr., his father, Bud, and a host of scientists, Navy officers, and newsmen were crowded aboard a U.S. Navy missile launching ship.
"Just think!" Bud exulted. "You'll have data from the planet Jupiter that no one on earth has yet been able to get!"
"If we recover the missile safely," Mr. Swift spoke up hopefully. The elder scientist's voice was quiet but taut with the strain of waiting. The two Swifts resembled each other closely—each had deep-set blue eyes and clean-cut features—although Tom was somewhat taller and rangier.
"You're right, Dad," Tom agreed. "If we don't snare the missile, our whole project will be a total loss to America's space program!"
At Tom's words, the watchers and crewmen who were crowded into the Recoverer's control room stirred restlessly. Its bulkheads were banked with radar and telemetering devices. Tension had been mounting throughout the morning aboard the ships and observation planes of the task force as everyone awaited the return of the planet-circling missile—scientists' deepest penetration into space so far.
"What do you mean, a total loss?" Bud argued. "Even if the recovery operation's a flop, the shot will still pay off in valuable information, won't it?"
Tom shook his head grimly. "The purpose of this unmanned, exploratory flight around Jupiter was to take and record all kinds of data. But none of the info is being radioed back to us."
"If we had put in radio gear strong enough to relay signals back, it would have cut down the amount of information-gathering equipment aboard," Tom explained. "We had to make every ounce count."
Outwardly calm, Tom was seething with inner excitement. Although only eighteen—the same age as his husky, dark-haired pal and copilot, Bud Barclay—Tom had been given the job of directing the recovery phase of the United States government's Project Jupiter survey. The Swifts and their rocket research staff had built the missile and engineered the space probe for the government.
"Whew!" Bud gave a nervous whistle. "I see what you mean, pal. With all our eggs in one basket, we sure can't afford to get butter-fingered with the Jupiter prober."
Admiral Walter, a tall, distinguished man, graying at the temples, smiled. "It's what we call in warfare a calculated risk, Bud," he said. "But with Tom in charge, I believe we have nothing to worry about."
Mr. Swift's eyes shone with fatherly pride at the admiral's remark. Tom Jr.'s pioneering rocket flights and inventions had won the youth a top rank in American space research.
"Guess you're right, sir," Bud agreed. "I'll back genius boy here any day!"
Tom winced as Bud whacked him heartily on the shoulder. "Better save your orchids and keep your fingers crossed, fly boy," the young inventor advised. "That rocket's not home yet."
Radio telescopes, both on land and aboard the ships of the task force, were following the missile's progress as it drew closer to earth. All were feeding a steady stream of information to the ships' computers.
"How soon will you fire the retro-rockets, Tom?" Admiral Walter inquired presently.
"In about ten seconds, sir," Tom replied, eying the sweep second hand of the clock.
Moments later, a red light flashed on the master control panel. Tom's finger stabbed a button. Far out in space, the retarding rockets in the missile's nose were triggered for a brief burst, slowing its high speed. Without this, the missile would hurtle to flaming destruction in the atmosphere.
"We've picked it up!" shouted a radarman.
Bud gave a whoop of excitement and everyone crowded around the radarscope. Tom's steel-blue eyes checked the blip. Then he threw a switch which started an automatic plotting machine that had been prepared with the landing plan, and noted that the missile was slightly off the correct path. A new flow of information now began pulsing in as other ships' tracking radars recorded its course. The data was being fed automatically to the "capture" computer. This would analyze the correct flight path for the recovery missile, which would magnetically seize the returning traveler from Jupiter and bring it safely home.
Tom quickly read off the results from the computer's dials, then busied himself again with the retarding-rocket controls.
"Everything going okay, skipper?" Bud asked.
Tom nodded. "I've readjusted the retarding rockets. They'll fire at the proper intervals to slow down the missile still further and bring it back on beam."
The excited buzz of voices in the compartment gradually quieted as the clock ticked steadily toward the next step in the recovery operation.
"Stand by for missile firing!" Tom snapped.
A seaman relayed the order over the ship's intercom. Tense silence fell as Tom's eyes followed the sweep of the second hand.
"All clear for blast-off!" came the talker's report.
Tom pressed the firing button. A split second later the listeners' eardrums throbbed to a muffled roar from topside as the slender recovery missile shot skyward. The ship rocked convulsively from the shock of blast-off. Then it steadied again as the gyros damped out the vibrations.
"Wow!" Bud heaved a sigh of relieved tension. Then he dashed from the compartment and up the nearest ladder for a quick look at the rocket as it disappeared into the blue.
Tom watched the recovery missile intently on the radarscope.
"Nice going, son," said Mr. Swift quietly.
In response to his father's reassuring grip on his arm, Tom flashed him a hasty smile. For the first time, the young inventor realized he was beaded with perspiration and that his pulse was hammering.
"It's a case of wait and hope," Tom murmured.
On every ship and plane in the task force, eyes were glued to the radar screens. Two small blips were visible—one the Jupiter probe missile, the other the recovery missile—moving on courses that would soon intersect.
Just as Bud returned to the compartment, several of the watchers gave startled gasps.
"Another blip—coming in from nine o'clock!" Admiral Walter exclaimed. "What's that?"
Tom stared at the new blip. It was moving steadily toward the meeting point of the first two missiles!
"It's a thief missile!" Tom cried out. "Some enemy's trying to steal our probe data!"
"Good night!" Bud gulped. "Who'd dare try that?"
"I don't know," Tom muttered tensely. "But if those three missiles meet, our whole project will be wrecked!"
"Better tape all readings!" Mr. Swift advised.
Admiral Walter had paled slightly under his deep tan. In stunned silence, the Navy officers and scientists watched as Tom's lean hands manipulated two controls.
"What are those for?" Bud asked.
"One's to speed up our recovery missile," Tom explained. "Looks like a slim hope, though, from the way that third blip is homing on target. This other control has just caused every instrument on this ship, and all the others in the task force, to make permanent records on magnetic tape of all their readings.
"If a collision occurs and the probe missile falls into the sea," Tom went on, "there's only one hope of recovery—to plot the exact geographical position and then get to the spot before the enemy does!"
"Roger!" Bud agreed.
It was obvious that Tom's fears about the missiles colliding were well founded. The mystery blip had veered as the recovery missile speeded up. Within seconds, the three blips met on the screen and fused into a single spot of light.
"The probe missile's no longer responding to control!" one of the telemetering scientists called out.
Admiral Walter, grim-faced, flashed a questioning look at Tom. "Then recovery has failed?"
"I'm afraid so, sir."
The fused blip was still visible on screen as the radar dishes tracked it, moving in a way that indicated a steep downward plunge.
For a moment Tom felt numb with despair. But he set his jaw firmly and turned to the admiral.
"Sir, I'd like helicopters readied for take-off immediately," Tom said. "As soon as the tracking instruments lose contact, have the recording tapes picked up from every ship in the task force and brought here to the Recoverer."
Admiral Walter nodded tersely. "Very well. Then what?"
"I'll get to work right now," Tom replied, "and lay out a computer program to process the readings."
The data—consisting of millions of information "bits" from the shipboard instrument tapes—would be fed to an electronic brain. The brain would then calculate the probable location in latitude and longitude of the sunken missile.
As the admiral snapped out orders, Tom exchanged a brief worried glance with his father. Each was pondering the same thought.
Could Tom find the lost Jupiter probe missile? Or would their enemy locate it first?
With an effort, Tom forced all thoughts of failure out of his mind and concentrated on the job at hand. In an hour he had the computer program blocked out.
Mr. Swift and several of the other scientists checked his work. Each nodded approval. By this time, the fused blip had long since disappeared from the radarscopes, indicating that the Jupiter probe missile—or what was left of it—had plunged to the ocean bottom.
"What's your next move, Tom?" Admiral Walter asked.
"No point in wasting time waiting for the computer results," Tom decided. "Suppose Bud and I fly back to Swift Enterprises and organize a search party."
"Good idea." As Admiral Walter extended a hand, his weather-beaten face softened. "And don't feel downhearted, son. You rate a Navy 'E' for the way you handled this operation. It would have succeeded if it hadn't been for that confounded enemy missile!"
"Thank you, sir." Tom managed a grateful grin, in spite of his discouragement.
Minutes later, the two boys embarked in a motor launch that took them to an aircraft carrier standing by in the vicinity. From the flattop they took off in a Navy jet for Shopton.
Meanwhile, Mr. Swift remained aboard the Recoverer to supervise the data processing. Tom, looking back from the soaring jet, could see one of the helicopters on its way to the missile ship to deliver the first batch of tapes.
It was late afternoon when the Navy jet touched down on the Enterprises airfield. The Swifts' sprawling experimental station was a walled, four-mile-square enclosure with landing strips, work-shops, and laboratories, near the town of Shopton. Here Tom Jr. and his father developed their amazing inventions.
Tom and Bud hopped into a jeep at the hangar and sped to the Administration Building, where Tom shared a double office with his father. Bud sank down into one of the deep-cushioned leather chairs, while Tom adjusted the Venetian blinds to let in the afternoon sunshine.
The spacious office was furnished with twin modern desks, conference table, and drawing boards which swung out from wall slots at the press of a button. At one end of the room were the video screen and control board of the Swifts' private TV network. Here and there stood scale models of their inventions, a huge relief globe of the earth, and a replica of the planet Mars.
"What are your plans for our search expedition, skipper?" Bud asked.
Tom ran his fingers through his crew cut. "Let's see. We'd better take the Sky Queen, I think, and also—"
Tom broke off as the desk intercom buzzed. Miss Trent, the Swifts' secretary, was on the wire.
"Your father's calling over the radio, Tom."
"Swell!" Tom flicked a switch to cut in the signal of his private telephone. "Hi, Dad! We just got back. Any news?"
"Yes, son. We have the computer results," Mr. Swift replied. "Got a pencil handy?"
Tom copied down the latitude and longitude figures as his father dictated.
"According to the latest hydrographic maps, based on IGY findings," Mr. Swift went on, "this area is a high plateau of the Atlantic Ridge—it's near the St. Paul Rocks."
"What about the depth?"
"It averages between a hundred and three hundred feet," said the elder scientist.
Tom gave a whistle. "Lucky break, eh?"
"Maybe and maybe not," Mr. Swift said cautiously. "The bottom there is heavily silted."
"Oh—oh." Tom made a wry face. "In that case, we may have some digging to do."
"I'm afraid so. However, no use borrowing trouble." After a short discussion, the elder scientist added, "I'll probably fly home tomorrow, son. Give my love to Mother and Sandy."
"Right, Dad. So long!" Tom hung up and reported the news to Bud.
"What kind of underwater gear will we use?" Bud inquired.
"I'm not sure myself," Tom admitted. "Guess we'll have to take along a variety of equipment and play it by ear."
Before proceeding with his search plans, Tom phoned home to inform his mother of his arrival. Mrs. Swift was sympathetic when she heard of the failure to recover the probe missile.
"I'm sure you'll locate it," she said encouragingly.
"Some of your cooking will sure help brighten the picture," Tom replied with a grin. As he put down the receiver a moment later, he told Bud, "You're having dinner with us tonight, pal. Fried chicken and biscuits."
Bud licked his lips. "Lead me to it!"
Chuckling, Tom began drawing up a list of supplies for the expedition. Bud helped with the details, after which Tom phoned the underground hangar and the Swifts' rocket base at Fearing Island to give the orders for the next day. Crewmen were also detailed for the trip.
It was six o'clock when the two boys finally piled into Tom's low-slung sports car and drove to the Swifts' big, pleasant house on the outskirts of Shopton. Sandra, Tom's blond, vivacious sister, greeted them at the door.
"About time!" she teased. "We were beginning to think you two had taken off somewhere."
"Think I'd leave town while you and that fried chicken are in Shopton?" Bud grinned.
"What a line!" Sandy's blue eyes twinkled. "I know it's the fried chicken you're really interested in."
"Where's the rest of that 'we' you were referring to?" Tom inquired.
"I'm sorry, Tom," Sandy said in a mournful voice. "Phyl couldn't make it."
As Tom's face fell, she burst out giggling and a second later Phyllis Newton emerged from the kitchen. Brown-eyed, with long dark hair, Phyl was the daughter of Tom Sr.'s old comrade-in-arms and lifelong chum "Uncle Ned" Newton. Like Sandy, she was seventeen.
"You didn't think I'd miss this rare evening, did you, Tom?" she said, laughing. "After all, it isn't often we see you two."
Sandy and Phyl liked to needle the boys about their infrequent dates, due to Tom's and Bud's busy schedules.
Mrs. Swift, slender and sweet-faced, gave Tom a hug and greeted Bud warmly. Over the delicious dinner, the conversation turned to the mysterious thief missile.
"Who on earth could have fired it?" Sandy asked.
Tom shrugged. "No telling—yet. There's more than one unfriendly country which would give a lot for the data picked up on our Jupiter shot."
"You aren't expecting more trouble, are you?" Phyl put in uneasily.
Tom passed the question off lightly in order not to alarm his mother and the two girls. But inwardly he was none too sure of what his survey expedition might encounter in trying to locate the lost probe missile.
Ever since his first adventure in his Flying Lab, the youthful inventor had been involved in many daring exploits and thrilling situations. Time and again, Tom had had to combat enemy spies and vicious plotters bent on stealing the Swifts' scientific secrets.
His research projects had taken him far into outer space and into the depths of the ocean. With his atomic earth blaster, Tom had probed under the earth's crust at the South Pole, and in other adventures he had faced danger in the jungles of Africa, New Guinea, and Yucatan. His latest achievement, receiving the visitor from Planet X, had been to construct a robot body for this mysterious brain energy from another world. Now, Tom realized, he was on the brink of another adventure which might hold unexpected dangers.
Early the next morning the majestic Sky Queen was hoisted from its underground hangar berth and hauled by tractor to its special runway. This mammoth, atomic-powered airplane had been Tom's first major invention. A three-deck craft, it was equipped with complete laboratory facilities for research in any corner of the globe. Jet lifters in the belly of the fuselage enabled the craft to take off vertically and also to hover.
As Tom supervised the loading of the equipment, a foghorn voice boomed, "'Mornin', buckaroos!"
The chunky figure of Chow Winkler came into view. Formerly a chuck-wagon cook in Texas, Chow was now head chef on Tom's expeditions. As usual, a ten-gallon hat was perched on his balding head and he was stomping along in high-heeled boots.
"Wow! A shirt to end all shirts!" Tom chuckled.
"Real high style, eh?" Chow twirled about to display his latest Western creation. The shirt seemed to be made of silvery fishlike scales, which glistened like a rainbow.
"I figured as how this was just the thing fer an ocean jaunt," Chow added with a grin. "How soon do we take off, boss?"
"As soon as we get the rest of this gear stowed," Tom replied.
Twenty minutes later the Sky Queen soared toward the ocean. Soon they came in sight of Fearing Island rocket base, a few miles off the coast. Once a barren stretch of sand dunes and scrub-grass, the island was now the Swifts' top-secret rocket laboratory, guarded by drone planes and radar. It served as the supply base for Tom's space station and as the launching area for all space flights. Seacopters and jetmarines were also berthed here.
A radio call from Tom brought a sleek, strange-looking craft zooming up to join them.
It was the Sea Hound, latest and largest model of Tom's amazing diving seacopter. It had an enclosed central rotor, powered by atomic turbines, with reversible-pitch blades for air lift or undersea diving. Superheated steam jets provided forward propulsion in either element.
As the Sea Hound streaked alongside the Flying Lab, two figures in the seacopter's flight compartment waved to Tom and Bud. One was Hank Sterling, the blond, square-jawed chief pattern-making engineer of Enterprises. The other was husky Arv Hanson, a talented craftsman who transformed the blueprints of Tom's inventions into working models.
"All set," Hank radioed. "Lead the way."
"Roger!" Tom replied.
Flying at supersonic speed, they reached the area of the lost missile in the South Atlantic soon after lunch. Already on hand were ships of the Navy task force assigned by Admiral Walter to participate in the missile search. The Sea Hound settled down on the surface of the water, while the Sky Queen hovered at low altitude nearby.
Tom contacted the government craft and learned that as yet no sign of the lost Jupiter prober had been detected. Then he made ready to begin his own search.
"Let's try the Fat Man suits first," Tom told Bud. Turning to Slim Davis, a Swift test pilot who was in the crew, the young inventor added, "Take over, will you, Slim?"
"Righto." Slim eased into the pilot's seat.
"Got a job for me, skipper?" asked Doc Simpson, Swift Enterprises' young medic.
"Yes. Help the boys, if you like, rig the undersea elevator, and then assemble a tractorized air dome," Tom suggested.
"Will do," Doc promised.
A ladder was dropped. Tom and Bud excitedly descended to the Sea Hound. The search for the lost missile was about to begin!
Once the boys were aboard, the seacopter submerged and dived quickly to the ocean floor. Tom and Bud each climbed into a Fat Man suit and went out through the air lock. The suits, shaped like huge steel eggs with a quartz-glass view plate for the operator seated within, had mechanical arms and legs.
The boys waddled about, the built-in searchlights of their suits piercing the murky gloom. They saw nothing but the deep accumulation of silt on the ocean bottom, which made the going difficult.
"This is too slow," Tom called over his sonarphone. "Let's try the air dome."
The dome was a huge underwater bubble of air, created by a repelatron device which actually pushed the ocean water away. The air supply inside was kept pure by one of Tom's osmotic air conditioners which made use of the oxygen dissolved in the water.
The air bubble, however, even with its jet-propelled platform, also proved inadequate for the research job. Its caterpillar treads repeatedly bogged down in the silt.
"Maybe the seacopter itself is our best bet," Bud suggested.
"Worth a try," Tom urged.
But the Sea Hound, too, had a serious drawback. Even with its powerful search beam sweeping the ocean floor as it prowled along, the explorers found their vision too limited.
Finally Tom said, "Bud, we could skin-dive at this depth."
"Let's give it a whirl," Bud urged.
The seacopter surfaced again, while the boys donned flippers, masks, and air lungs. Then they dropped over the side and made their way slowly downward into the gray-green depths, accustoming themselves gradually to the increased pressure.
"A lot more freedom of action," Tom thought. "If only we didn't have to communicate by signals!"
There was a sudden swoosh somewhere on his right. A projectile, Tom realized! Turning, his eyes widened in horror as he saw an uprush of bubbles.
Bud's air tank had been hit!
Without wasting a moment, Tom lunged through the water toward his stricken friend. Bud was floundering and thrashing about weakly. He seemed dazed by the sudden shock of his plight.
"Or maybe the impact of the projectile stunned him!" Tom surmised.
Bud began groping his way upward just as Tom came alongside of him. Tom grabbed him as best he could, hooking onto his belt. At the same time, the young inventor inhaled deeply, yanked out Bud's useless mouthpiece, and inserted his own in its place.
Bud's eyes glowed with gratitude.
"We'll have to get topside fast," Tom thought, "even though it means risking the bends."
He stroked upward and they shot toward the surface. Bud assisted to some extent, partly revived by the gulp of air.
As they rose, fathom by fathom, their progress seemed to grow maddeningly slower. Tom had to let air bubbles escape constantly from his mouth. As the pressure decreased, due to the lessening depth of the water, the air in his lungs expanded and he was forced to breathe out.
Tom noticed with dismay that Bud was not responding very well, his feeble strokes were jerky and uncoordinated. "Must've lost pressure too fast when his tank was hit," Tom realized.
The water was growing greener and brighter now as they neared the sunshine. The Sea Hound's shadowy outline loomed just above. With a last desperate burst of strength, Tom lunged upward and they broke water.
"H-h-help!" Tom gasped.
There was no need for the cry. Hank and his crew, on the seacopter's forward deck, had already grasped the situation. Strong arms reached out and hauled the two boys aboard.
Both of them were shivering and writhing in pain, only half conscious.
"They have the bends!" Arv Hanson cried in alarm. "Signal the Sky Queen to drop a sling!"
The boys' masks were ripped off. Within moments, Bud had been tightly secured to the sling, which was reeled back up into the plane. Tom followed in a few minutes. Doc Simpson took charge of the patients immediately. After a quick examination, he had the boys placed in a small decompression chamber in the Sky Queen's sick bay.
"How are they?" Hank asked anxiously as he peered through the window of the chamber. The medic had given Bud a sedative and he was already fast asleep. Tom remained awake.
"Aside from the pain, not in too bad shape," Doc Simpson replied.
It turned out that Tom's case was not so serious, but Bud had to stay in bed. With Tom, it was only a matter of decompression and he soon was up and about.
Chow, in a chef's cap, with an apron around his paunchy stomach, had come stomping in hastily from the galley. "Pore lil ole boys," he fussed. "Brand my snorkel, I never should've let you young'uns go pokin' around down below there without me around to keep an eye on things!"
Tom slapped the loyal old Texan on the back. "If you want a dive, come along."
"You're goin' back down?" Chow asked.
"In the seacopter," Tom replied. "To find out, if possible, who fired that projectile at us."
"Then count me in!" Chow declared, stripping off his apron. "I just hope I get my hands on them sneakin' polecats!"
Slim Davis would pilot the Sky Queen back to Shopton at once, because of Bud. Tom and Chow, meanwhile, would join Hank and his crew aboard the Sea Hound.
Ten minutes later the sleek seacopter, its searchlight off to avoid detection, was plummeting downward through water that changed before their eyes from greenish blue to a deep-gray gloom. Iridescent fish darted past the cabin window.
"Think the enemy sub was searching for our Jupiter prober?" Hank asked.
"It must have been," Tom reasoned.
Hank frowned. "Which means they must have figured out the missile's position as fast as our side did."
"And they'll play rough to stop us from finding it," Arv added forebodingly.
Within moments, the group clustered in the pilot's cabin felt a gentle bump as the Sea Hound settled on the submerged plateau. Tom relaxed at the controls but kept the rotors going so the craft would remain submerged. Meanwhile, the sonarman was probing the surrounding waters.
"Any pings?" Tom asked.
The man shook his head without taking his eyes from the sonarscope. "Nothing yet."
Hank Sterling donned a hydrophone headset and listened intently. The silence deepened in the Sea Hound's cabin. Suddenly Hank stiffened and the sonarman cried out:
"A blip, skipper! At two o'clock!"
It was moving rapidly on the scope—something streaking toward their starboard beam!
"Good night! It's another missile!" Tom gasped.
He darted back to the controls and gunned the reverse jets just in time! The missile flashed across their bow.
"Great bellowin' longhorns!" Chow gasped weakly. His leathery face had gone pale under its tan. "The yellow-livered drygulchers!"
"I don't get it," Arv Hanson spoke up. "If they're in firing range, we should have detected them, shouldn't we?"
Tom nodded grimly. "Whoever our enemies are, they must have perfected a way to make themselves invisible to underwater detection.
"And we'll have to do the same!" he vowed inwardly. Aloud, Tom said, "I hate to run from those sneaks, but if we stick around, we'll be asking for trouble."
Slowing the rotors to permit the craft to rise, Tom guided the Sea Hound back to the surface. Then he reversed blade pitch for air flight and gunned the atomic turbines. The seacopter rose steeply above the billowing South Atlantic.
Tom radioed a terse report of their experience to the task-force commander and in turn was told that none of the naval craft had either sighted or picked up any sign of a strange sub.
As they streaked homeward, Chow was still fuming. "Why don't we post a dummy sub there to scare off the varmints?"
"I'll pass the idea along to the Navy," Tom said with a grin.
Night had fallen when the searchers arrived back at Fearing Island. Tom cleared with the tower and landed, then went by jeep to base headquarters. He called Enterprises and learned that Bud's condition was improved, and that Mr. Swift had returned that afternoon. He spoke to him about the mystery sub.
"This is bad news indeed, son," Mr. Swift said, after hearing how the attacker had defied detection. "You'd better inform Admiral Walter. He had to fly back to Washington."
"I'll call him right away," Tom promised.
The admiral was equally disturbed when Tom succeeded in reaching him. "We must find that missile as soon as possible—at any cost," he said. "Tom, you Swifts have had considerable experience in undersea dredging. Could you send a team of engineers to assist us in the work?"
"Yes, sir," the young inventor replied. "I'll assign men to the job first thing tomorrow."
After hanging up, Tom hopped back to the mainland with Chow in a Pigeon Special. This sleek little commercial plane was manufactured by the Swift Construction Company in charge of Ned Newton.
Early the next morning Tom and his father drove to Enterprises, and the young inventor plunged into the job of organizing an engineering crew for the missile hunt. Art Wiltessa, a crack underwater specialist as well as engineer, was placed in charge.
By noon the group had taken off for the South Atlantic in a Swift cargo jet. A small portable model of Tom's atomic earth blaster was included in their equipment. A jetmarine and a diving seacopter were also dispatched from Fearing to assist in the operations.
"It's apt to be a long-drawn-out job—and dangerous," commented Mr. Swift as he lunched with Tom in their office.
"Yes. Digging in that silt could be almost as bad as working in quicksand."
Mr. Swift's deep-set blue eyes took on a thoughtful gleam. "Speaking of silt, son, I've found the ideal spot for my secret deep-sea farm."
"You mean for growing those plants you use in making Tomasite?" Tom asked.
The elder scientist nodded. Tomasite, a revolutionary plastic which Mr. Swift had developed, possessed amazing insulating properties against both heat and radiation. One of its secret ingredients came from certain plants found only in Far Eastern waters. Mr. Swift hoped to transplant them locally.
"The site is near Fearing Island—about fifty feet in depth," he added.
"You may have a tough time finding gardeners, Dad," Tom pointed out. "Men can't work that far down for very long at one time."
"It'll be a problem," Mr. Swift conceded. He finished his coffee, then looked up with a twinkle in his eyes. "How about figuring out a solution for me, Tom?"
"A new kind of air lung?" Tom was intrigued!
"Yes, son," Mr. Swift went on. "What's needed is a new type of breathing device—one that will eliminate bulky air tanks and permit a skin diver to stay down for long periods."
"Quite an order, Dad."
Grabbing a pencil, the young inventor began sketching. In both his Fat Man suits and his osmotic air conditioner, Tom had already perfected ways of drawing oxygen from sea water.
"But a small gadget for skin divers," he said, "will take a fantastic job of electronic miniaturization." After a pause he added, "It could really speed up recovery of the Jupiter prober, though."
Lunch over, Tom hopped a jet scooter and sped off to his private laboratory. The modernistic glass-walled structure—designed by Tom himself—had every tool of modern scientific research, from electronic microscope to helium cryostat.
As always, whenever he was absorbed in a new idea, Tom was eager to get to work. "Let's see what I'm shooting for. A small container, slung around the diver's neck?... No, too dangerous. Better hook it to his weight belt, with a tube to his face mask."
Using a plastic foam "breadboard," Tom began experimenting with various circuit designs. He worked through the afternoon and returned to the problem early the next morning.
He was interrupted by a message from Art Wiltessa, reporting no luck so far in finding the missile. Later, shortly before lunch, Tom received another call, this time from Admiral Walter. "Just wanted to keep you posted, Tom. Our task force reports no success on their part in finding the buried missile. No sign of the enemy, either."
"They'd probably hesitate to attack any official U.S. Navy units," Tom said. "Or it might mean they've already found the missile themselves."
"That's what I fear," Admiral Walter confessed gloomily. "However, we'll continue searching."
Tom promised to fly down to the site at the first opportunity, saying he was developing a new device that might assist in the search. After snatching a hasty lunch, Tom returned to work.
Arv Hanson machined several parts and molded the plastic face mask to Tom's specifications. By evening the new device was completed.
"Now for a test," the young inventor said to himself.
Sandy Swift and Phyl Newton were eager to watch the test, so the next morning they drove to the plant in Phyl's white convertible. Tom, clad in swim trunks, was waiting for them with Chow near the edge of a mammoth concrete tank. Set in bedrock, at one end of the Enterprises grounds, the tank was used for submarine testing.
When Sandy saw the power unit strapped to Tom's weight belt, she exclaimed, "That little gadget will supply all the air you need? Why, it's no bigger than a pocket transistor radio!"
Tom grinned. "I hope it will. That's what I intend to find out."
"How does it work?" Phyl asked, fascinated.
Tom explained, "Actually its function is to replace the carbon dioxide that I exhale with fresh oxygen drawn from the water. Otherwise, although the carbon dioxide I'd breathe out would be a very small amount at a time, it soon would make the air unfit. The nitrogen, which makes up much of the air we breathe, is chemically inert and can be used again and again."
He pointed to a round screen on one side of the unit. "This is the water intake," Tom went on, "and this other screen is where the water comes out after we've removed its oxygen."
Near the forward end of the unit, a semirigid plastic tube was connected, leading up to the face mask. At the rear was a power port for inserting a small solar battery.
"What about this little tuning knob?" Sandy asked.
"That's the rate control for adjusting the output frequency to the wearer's breathing rate." Tom added, "I've decided to call the whole apparatus an 'electronic hydrolung.'"
Chow pushed back his ten-gallon hat and scratched his head dubiously. "Wal, I'm keepin' a net handy to drag you out, boss, just in case."
Tom chuckled and fitted the mask over his face, then made a clean dive into the tank. For the next ten minutes the girls and Chow watched wide-eyed as he swam, walked around, and went through vigorous exercises at the bottom of the tank without once coming up for air.
"Whee!" Sandy exclaimed when Tom finally climbed out. "Make me one, so I can take up skin diving!"
"It's wonderful!" Phyl added admiringly.
Tom took off his mask. "I'm pretty pleased with it myself," he admitted, grinning.
The girls stayed at Enterprises for lunch. Then the group, accompanied by Doc Simpson, flew to Fearing Island so Tom could test his invention in deep water. Boarding a small motor launch, with Doc at the helm, they cruised out to a suitable depth and dropped anchor.
"Don't become too confident, Tom," Doc warned. "I'll drop a signal line over the side in case of emergency."
Tom buckled on his equipment belt and adjusted the face mask. Then he held up crossed fingers and back-flipped over the gunwale into the water. Chow, Doc, and the girls watched his plummeting figure fade from view.
Tom, an expert skin diver, had never before felt such a sense of ease and freedom under water. He was moving, light and self-contained, in a green, magical world. With no air tanks chafing his back, he felt akin to the fishes themselves.
"Wish I'd brought a hook and line along." He chuckled, as a school of mackerel darted past.
Now came the real test. Deeper and deeper, Tom cleaved his way downward. Reaching bottom, he prowled about the ocean bed for a while, then started up again. Suddenly a stab of pain shot through his chest—a warning of nitrogen bubbles forming in his blood!
Tom swam toward the signal cord, dangling dimly in the distance. By the time he reached it, his muscles were knotting with cramps.
"It's the bends again, all right!" Tom realized. Gritting his teeth, he yanked hard on the line, then summoned his strength to hang on.
Doc and Chow hauled up frantically. Tom's face was contorted with pain when they finally got him aboard and stripped off his mask.
"Oh! How awful!" Phyl gasped.
Sandy cradled Tom's head in her lap, and Phyl held his hand sympathetically, while Doc Simpson injected a hypodermic to ease the pain. Chow steered the launch back to shore, and Tom was rushed to the base infirmary in an ambulance.
Here he was placed in a decompression chamber for several hours and later transferred to a hospital bed. Bud Barclay came to visit him.
"We're a fine couple of fish," he said.
Tom chuckled wryly. "Live fish, anyhow."
"In my case, thanks to you," Bud said.
"Forget it, pal. The score's about even, I should think," Tom said, recalling the many life-or-death adventures they had shared.
Bud was thrilled to hear of Tom's electronic hydrolung. The young inventor spent the evening sketching out an improved design to eliminate future accidents.
"I'll install a special device to remove the nitrogen as the wearer exhales," Tom explained. "Then a valve will feed in helium to replace it. Since helium doesn't dissolve in the blood like nitrogen does, it will not bubble out when the pressure is reduced. Should have thought of that before!"
"But you'll need a tank for the helium, won't you?" Bud objected.
Tom shook his head. "Enough can be compressed into a small capsule to supply the wearer's needs. Remember, it can be used over and over again."
"Pretty neat," Bud commented.
By morning Tom felt thoroughly recovered. He insisted upon flying back to Enterprises to make the necessary changes in his hydrolung. Bud accompanied him, eager to get back on the job.
In a few hours Tom had added a small fitting to his power unit to provide for helium substitution. Then the two boys hopped back to Fearing for a second deep-water test. This time, Tom was delighted to find that he could operate comfortably at great depths, as well as rise or descend suddenly without ill effect.
Bud was aglow with enthusiasm. "Boy, we can really explore now!"
After the boys had returned to Enterprises, Tom phoned Arv Hanson and asked that a duplicate of the hydrolung be turned out in the shop as soon as possible. It was ready the following Monday morning, so Tom suggested to his father that the two visit the proposed underwater site and make some sample plantings.
"Great idea, son," Mr. Swift agreed. "I want to try out your new diving apparatus myself. If it's successful, we'll be able to tackle two problems at once—recover the Jupiter prober and start the 'sea farm.'"
They flew to Fearing, then went by boat to the farm site, about half a mile offshore. Each carried several of the valuable Far Eastern plants.
The silt beds which Mr. Swift had selected were just deep enough to keep the plants from being discovered, yet enable them to receive sufficient sunlight.
Tom and his father started their planting. But no sooner had the first plants been embedded than fish darted in to nibble them. Even the roots disappeared into their greedy maws.
"Looks as though we'll have to build some sort of net enclosure around and over our farm," Mr. Swift said, after they had climbed back into the boat. "But at least your hydrolung device is a great success, son!"
Tom was thoughtful. "Dad, I wonder if the fish would eat those plants from space which you've been growing under salt water?"
Tom was referring to certain strange plants rocketed to earth by unknown space friends with whom the Swifts had been in communication.
"I have a hunch," Tom went on, "that the fish might be repelled by the unusual scent of those space plants. If so, we could scatter them among the earth plants to keep the fish away."
Mr. Swift was impressed by Tom's idea. As soon as they had returned to Enterprises, he proposed that the experiment get under way.
Tom volunteered to undertake the job at once with Bud. While the young inventor phoned his copilot, Mr. Swift went to his own laboratory to prepare the plants for shipment.
Twenty minutes later the boys took off in a jet. The plants had been parceled in transparent plastic film. Glistening with a red metallic sheen, they looked somewhat like tulips with honeycombed centers.
"Scarecrow plants to drive off fishes," Bud joked. "What will scientists think of next!"
Tom laughed, then abruptly frowned. "Hey! What's that character up to?" he said. "Trying to buzz us?"
A sleek gray jet without markings was arrowing in on them from three o'clock. Bud flicked on the radio and barked a warning. The plane made no response. As it kept coming, Tom increased speed—then rolled, dived, and changed course, but failed to shake off their pursuer.
Bud, meanwhile, was frantically calling Enterprises and a nearby airport, but getting no response. Yet their radio was working, for a voice suddenly crackled:
"Follow the mystery plane for a landing and you won't be harmed!"
A HUNCH PAYS OFF
Dismayed, Tom and Bud stared at each other. Apparently the enemy ship had blanked out their radio communication to all points except the mystery plane.
"Who are you and what do you want?" Tom said into his microphone.
The voice replied crisply, "You'll find out when the time comes!"
Tom flicked off his mike and exchanged another worried glance with Bud. "We seem to be in a spot, pal!"
"And how! Especially if that crate's armed!" Bud muttered. "But what are they after?"
Tom shrugged. "The space plants maybe—or possibly our jet."
"Might even be us they want," Bud said. "Got any tricks under your magician's hat?"
Tom's brain was already racing to figure a way out. Suddenly he snapped his fingers. "Hey! I almost forgot!" he exclaimed. "Look in the locker, Bud, and see if we have the radio set that neutralizes all interference!"
Bud's face brightened. "Now you're talking!"
The set had been perfected during Tom's Cosmic Astronauts adventure, in defense against an Oriental enemy's jamming-wave generator. Bud found it in the locker, dragged it out joyfully, and plugged it into the power supply.
Meanwhile, the mystery jet had banked in a wide circle and headed west. As Tom stalled for time, it swooped back again and the same voice came snarling over the speaker.
"I warned you to follow us! Or would you prefer to be shot down?"
As if to back up the threat, a burst of tracer fire grazed Tom's plane.
He hastily switched on his mike. "Okay, hold your fire! I guess we have no choice!"
The jet turned back on its westerly course, and Tom followed obediently. Meanwhile, Bud had warmed up the other radio and contacted Enterprises. Tom switched mikes long enough to report their position, course, and speed, adding:
"Tell Security to alert Vignall Air Force Base pronto!"
"Roger Wilco!" the Enterprises operator responded. Even if the enemy ship detected the call, Tom knew the automatic scrambling device would prevent the message from being understood.
Minute after minute, the flight continued. "Where are they taking us?" Bud muttered.
"Some out-of-the-way landing spot probably," Tom conjectured. "I wonder how soon those fighter boys will—"
Bud suddenly grabbed Tom's arm and pointed to starboard. "There they come, skipper!"
Three gleaming specks had just burst through a cloud bank to the north. Closing in rapidly, they were soon visible as Air Force fighter jets, flying in V formation.
"Fighter One to unmarked jet!" came the sharp command over the radio. "Can you read me?... You'd better read me, pal! I order you to proceed to Vignall Air Base under our escort or take the consequences!"
The mystery pilot, evidently bewildered by the sudden onslaught, made a frantic effort to escape. But the fighters, with almost contemptuous ease, quickly surrounded the plane and forced him to comply with orders.
Bud whooped with laughter. "Just a sheep in wolf's clothing, eh, buster?"
Minutes later, all the planes, including Tom's, landed at the airfield. Four sullen-faced men, their hands up, emerged from the mystery jet. Military police with drawn automatics herded them to the commandant's office. Tom and Bud followed.
"Attempted aerial piracy, eh?" the commandant said when he heard the boys' story. Turning to the prisoners, he snapped, "Who are you, and what's the meaning of all this?"
The crew captain, a hard-looking, stockily built man of about forty-five, rasped back, "We have nothing to say."
The commandant wasted no words. "Search them," he told the MP's.
Their wallets and various other items revealed little. The crew captain was carrying a private pilot's license on which he was identified as "Jack Smith." The names of the others, as shown on identification papers of one kind or another, sounded equally false.
"Probably all forged," the commandant muttered, "but we'll check them out."
He tried again to glean something from the prisoners, but they replied with sneering evasions. The commandant reddened with anger at their stubbornness. "All right. Take them to the guardhouse," he ordered.
As the MP's marched the hijackers off, Tom asked how their case would be handled.
"The crime is a federal offense," the commandant explained. "Air Force Intelligence will co-operate on the case, but the prisoners will be turned over to a federal marshal."
Tom briefed him on the background of the situation, including the Jupiter-probing missile mystery, then asked, "Could those men be transferred to the Shopton jail for the time being so our own security setup can take a hand in the investigation?"
The commandant nodded. "I'll arrange it."
As the boys flew back to Enterprises, Bud threw Tom a quizzical glance. "How come you mentioned the Jupiter prober, skipper? Do you think those hijackers were after information?"
Tom shrugged. "I'm wondering myself, Bud. If they were, it could mean our enemy hasn't found it yet!"
When they arrived at the experimental station, Tom made a full report to Harlan Ames, the slim, dark-haired security chief. Ames listened thoughtfully but was as baffled as Tom.
"Are the men Americans?" he asked.
"I doubt it," Tom said. "They speak English well enough, but with a faint accent. Somehow, I have a hunch they're Brungarians."
Ames whistled. "That could spell trouble, skipper." More than once, Brungarian rebel agents had engaged in brazen plots against America and the Swifts.
"Let's hope I'm wrong," Tom said wryly.
"Art Wiltessa—and the Navy—called again," Ames added. "Still no luck on the missile search."
The gloomy news did nothing to lift Tom's spirits. The next day, hoping to verify or disprove his suspicion, he drove to Shopton Police Headquarters with Harlan Ames. The two talked briefly with Chief Slater, an old friend. Then a turnkey took them to the cell block.
The four prisoners had been confined in a single large cell. They seemed tense and angry—as if they had been quarreling among themselves.
"Ready to talk yet?" Ames asked. Getting no reply, he repeated the question in Brungarian.
Ames's ruse failed. "What language is that?" asked "Captain Smith" mockingly. "Pig Latin?"
As his cellmates grinned, Tom's eyes roved over their faces. One man—wavy-haired with penetrating dark eyes—seemed oddly familiar. Why? Suddenly the answer hit Tom like a flash. He resembled Streffan Mirov, the brilliant Brungarian rocket scientist who had tried to oust Tom's expedition from the phantom satellite Nestria.
Playing a hunch, Tom said to him, "You know what your government does to rebels and bunglers, Mirov."
The man stiffened and paled. "We have not b-b-bungled!" he stuttered angrily.
"Shut up, you fool!" their leader shouted.
THE CAISSON CLUE
"Captain Smith" had leaped to his feet, quivering with anger. But it was too late. His cellmate, by answering to the name of "Mirov," had given away their nationality!
Tom and Ames exchanged grins of triumph.
"No doubt you recall what happened to Streffan Mirov," Tom went on, pressing his advantage. "Or should I say the late Streffan Mirov? Our last report was that he had been tried and condemned by your own government. Perhaps you can give us news of his fate?"
The wavy-haired prisoner's eyes blazed with hate. "Grin while you can, Tom Swift! Because of you, my brother Streffan is now serving a long prison sentence! But I, Dimitri Mirov, will get revenge!"
"You blame Tom Swift because your brother botched his job of claiming the satellite Nestria by force and fraud?" Ames taunted.
"Our space friends moved that asteroid into orbit around the earth," Tom added. "We claimed it by right of first landing. Even your own leaders couldn't agree to Streffan's crazy scheme to destroy everything."
Dimitri Mirov lost all control and burst into a volley of guttural Brungarian abuse.
"I warn you, Swift!" he choked. "Jailing us will not make you safe—or your projects, either!"
A blow to the head from "Captain Smith" sent Mirov reeling back against the wall. "Fool! Maybe that will quiet you!" the pilot snapped viciously. "You have said too much already!"
"Let's go, Tom," said Ames. "We've learned the information we came for."
The prisoners could only glare in baffled rage through the cell bars as Tom and the security chief turned their backs and walked away.
"Nice going, Tom," Ames murmured. "Your hunch certainly paid off." Chief Slater added his congratulations when he heard how Tom had trapped Mirov into disclosing his identity.
Both Tom and Ames were grave as they drove back to the plant. Neither took Mirov's threats lightly.
Tom pondered another angle. Were the Brungarian rebels perhaps responsible for the attempted theft of the Jupiter-circling missile?
Ames was inclined to think so. "Moreover," he forecast, "it's a cinch they haven't thrown their last punch. I'll pass the word to the FBI and Central Intelligence."
After lunch Tom flew to Fearing Island with Bud, eager to tackle their interrupted job of rooting the space plants into the undersea silt beds. Zimby Cox, a sandy-haired, freckle-faced jetmariner, volunteered to pilot a motor launch for them.
They sped across the water, then dropped anchor at the farm site. Tom and Bud donned their hydrolung gear and went over the side, each clutching containers of the space plants.
Reaching bottom, they glided about in the shadowy green water, embedding the plants at far-spaced intervals. The Tomasite-producing plants had been almost completely devoured. A few fish were darting about, but they swam off quickly at the boys' approach. To Tom's delight, they showed no sign of returning.
"Looks as if our keep-off signs are working," Tom said with a pleased chuckle when the boys finally surfaced and climbed back aboard the boat.
Bud nodded. "Smart idea, all right." Then he scowled thoughtfully. "But if you ask me, skipper, fishes aren't the only thieves you'll have to guard against."
"Mirov's pals," Bud replied. "If it's the space plants they were after when they pulled that aerial hijack attempt, they could take them easily from these silt beds."
Tom sobered. "You have a point there. I'd better have an audio screen set up around this whole area. That'll act as a burglar alarm—and help discourage the fish, too."
Twenty minutes later the boys were winging back to the mainland. When Tom reached his office, he called in Gib Brownell, an Enterprises engineer.
"Got a job for me, skipper?"
Tom handed him a hastily scribbled diagram of the audio-screen setup. "One of those hurry-up deals, Gib," he said with an apologetic grin. Tom explained his plan. "We'll use transmitter buoys, monitored by an alarm system at base headquarters on Fearing."
Brownell studied the diagram and nodded. "Right. We can have it set up in twenty-four hours."
As Brownell left the office, the telephone jangled. Tom reached for it.
"Admiral Walter calling." His voice was tense. "Important news, Tom. One of our subs has picked up a clue that someone has been operating in the missile search area."
"What sort of clue, sir?" Tom asked.
"A compressed-air caisson for underwater work. It had been driven into the silt and then abandoned." Admiral Walter added that photographs and a section of the caisson were being flown to the Naval Research Laboratory for careful study. "I'll have a full report transmitted to you by video as soon as it reaches my desk."
Tom thanked the admiral and hung up, feeling more uneasy than ever. The report came through the following morning. Tom absorbed the contents, then gave a low whistle.
"Trouble?" asked Bud, who had just dropped into the office with some flight-test data on a new Swift superjet.
"Our old enemies again." Tom shoved the papers across his desk.
The report stated that both the design and manufacturing techniques used in making the caisson indicated that it was of Brungarian origin. A spectrographic analysis of the steels confirmed the theory. Their metallurgical content agreed with known Brungarian steel formulas.
"The sneaky rats!" Bud cried out. "Well, at least we know now who sabotaged our missile recovery."
As Tom paced about the office, Bud added, "What do you suppose they were using the caisson for?"
"Probably as a base for some heavy, rotating search equipment," the young inventor surmised.
"But why ditch it?"
Tom shrugged. "An optimistic guess is that they spotted our Navy search force and pulled out quickly, fearing a surprise attack."
"What's a pessimistic explanation?" Bud asked.
"Mission completed," Tom said grimly. "No need for them to stick around if they'd already snagged the missile."
Bud scowled at the thought. "Oh, no! That mustn't be true!"
Tom plopped down at his desk, frowning. "Bud, I've been itching to get to work on a non-detectable sub, like the one that attacked us. But maybe it would be smarter to get a line on Mirov's pals first."
"You mean down in the South Atlantic?"
Tom nodded. "I'd sure like to know if they found that missile."
"You and I both, pal!" Bud agreed. "Hey! We could use the electronic hydrolungs for scouting around!" he added eagerly.
"I intend to," Tom said. "But we'll need speed to cover the area. So first I want to add an ion drive to our equipment."
"Ion drive? For underwater?" Bud, who was familiar with ion propulsion for spaceships, wrinkled his brow in a puzzled frown.
"A goofy idea just occurred to me, but I think it may work out," Tom replied. He seized a pencil and began explaining what he had in mind.
The drive unit would take water into itself, separate the ionized molecules, and expose them to an electric field. Thus a stream of water would be forced out. This procedure, in turn, would set up a siphoning action through a central tube—in effect, creating a small but powerful water-jet motor.
"We'll be human submarines!" Bud exclaimed.
By the time Bud left the laboratory half an hour later, Tom had already plunged into work on his newest invention. The idea was simple enough in itself, Tom felt. The main problem would be the design job—laying out a compact, lightweight unit which a swimmer could easily carry on his back.
Fascinated, the young inventor worked late into the evening, stopping only in response to a telephone plea from Mrs. Swift. By midmorning the next day, Tom had assembled a pilot model of his ion-drive jet. In appearance, it was a slender metal cylinder, two feet long, with an inner concentric tube projecting at each end.
Tom had ordered a tank set up in his laboratory to test the unit. The tank was filled chest-deep with water, and the ion drive was mounted on a unitrack running the length of it. Tom set up his control board alongside, with the main power switch within easy reach. The drive unit was connected to the board by a suspended cable.
"Boy, this'll be like playing with a speedboat in a bathtub!" Tom thought with a chuckle as he changed into swim trunks.
He climbed into the tank and slid the drive unit to one end of its track. Then Tom metered out power slowly. With a gentle whoosh, the ion-drive unit whizzed along the unitrack to the other end of the tank.
"Not bad," Tom muttered, a pleased grin on his face. "Now I'll rev it up a little."
He slid the drive unit back to starting position, then opened the switch wider. He had just started across the tank himself when suddenly he became powerless to move.
Tom was pinned helplessly against the wall of the tank by the powerful water-jet exhaust! And the control switch was beyond his reach!
"Good grief! I'm trapped!" Tom squirmed desperately in a vain attempt to free himself.
The ion-drive unit had hurtled to the far end of the tank at the first flick of power. But its exhaust tube was still jetting out a current of water with stunning force. Tom could feel the near-crushing pressure against his chest, even the full length of the tank away!
"H-h-help!" Tom gasped.
Moments dragged by with agonizing slowness. Tom felt as if his last ounce of breath were being squeezed out by the viselike pressure.
Suddenly a gravelly Western voice reached him, singing "Home on the Range." It drew closer, swelling into a foghorn drone as the lab door swung open.
"Good old Chow!" Tom thought. "Thank heavens!"
The grizzled, bowlegged cook ambled cheerfully into the laboratory, pushing a lunch cart. But, to Tom's dismay, he cast only a passing glance at the figure in the tank.
"Soup's on, son!" Chow announced loudly. He began to ladle out a bowl of oyster stew from a steaming pot. Evidently he had not realized the young inventor's dilemma!
"Extra good today too, if I do say so myself!" the old Texan went on, setting out the rest of the lunch. "Well, come on, buckaroo! Break away from them chores an' dive in! Brand my cactus salad, if there's one thing that riles a cook—"
Summoning all his strength, Tom croaked out weakly, "Chow!... Get help!"
At the strange sound of Tom's voice, Chow jerked around. His eyes bugged out at the look on the young inventor's face. Then he dashed to the public-address outlet on the wall and switched on the mike.
"Help! Help!" Chow yelled. "Tom Jr.'s trapped in his lab!"
The roly-poly chef was quivering in panic. He dashed across the room and paced helplessly about the tank. Within moments, excited men were crowding into the laboratory.
Mr. Swift, among the first to arrive, took in the situation at a glance. He dashed to the control board and slammed shut the main switch, thus cutting off power to the ion-drive jet.
"Whew! Th-thanks, Dad!" Tom's chest was heaving as he gulped in air to relieve his tortured lungs.
Tom Sr. helped him climb out of the tank.
"B-b-brand my rhubarb rockets," Chow stuttered. "What in tarnation happened?"
"Guess I gunned my new skin-diving jet a bit too hard," Tom said sheepishly. "It was almost a K.O. for me!"
Mr. Swift asked Tom about the invention. After explaining how it worked, Tom added with a grin, "Maybe you'd better hang around, Dad, until I install some sort of density-control gadget for my hydrolung. Then I can go up or down, or stay at any level easily."
Such a device, Tom felt, might prove to be a lifesaver if he should ever become trapped under water—perhaps far from help.
The elder scientist chuckled and threw an arm around Tom's shoulders. "I'd say you could design something like that with your eyes shut, son!"
Warmed by his father's appreciation, Tom set to work improving his diving apparatus.
An hour later Bud came bursting into the laboratory. "Hey! What's this I hear about your getting hammerlocked by a water jet?" the husky young pilot asked. He had been on a test flight and just returned.
Tom laughed good-naturedly. "Nothing serious. In fact, I felt pretty silly," he told his chum. "I souped up our ion-drive gizmo a bit too much."
Bud picked up the slender metal cylindrical assembly from the workbench. "This it?" he asked, his curiosity immediately aroused.
Tom nodded and demonstrated the device in the test tank.
Bud whistled with glee. "Boy! With this rig, we can scoot around like a pair of barracudas!" he exclaimed. "What about that other thing you're working on?" Bud pointed to a small electronic chassis on the workbench, studded with a tangle of transistors, diodes, and condensers.
"It's a density-control device," Tom explained. "A substitute for ballast tanks, you might say. It'll enable us to rise or sink to any depth at will, simply by varying our underwater density."
Tom said the device would be carried in a small case, hooked to the diver's belt, with a single tuning-knob control. The "throttle" or speed control for the ion drive would be housed in the same unit.
"I can't wait to try out the new diving gear," Bud said excitedly.
By four o'clock Tom had the apparatus perfected, and turned it over to Arv Hanson for fast duplication.
"We'll give it a shakedown tomorrow morning," he told Bud.
The duplicates of the ion drive and density control were ready and waiting when the boys arrived at the plant next day. They immediately flew to Fearing Island and embarked in a motor launch, with Zimby Cox again at the helm.
This time they cruised out to deeper water. Tom and Bud donned flippers and belt, and helped each other strap on his ion-drive jet.
"Down we go, into the wilds of sharks!" Bud chortled lustily. "Watch your step, Tom."
"Just make sure you come up again in one piece," Zimby said with a grin. "Also, don't get carried away with that ion squirt gun and take off on a round-the-world underwater cruise."
"Who knows?" Tom joked. Adjusting his face mask, he plunged over the side. Bud followed.
Down they glided into the sea-green wilderness. Leveling off in sight of the ocean floor, they tried their drive jets. The effect was thrilling! Zip ... Whoosh! They darted to and fro like human torpedoes.
Then Tom twirled the control knob of his density unit. Immediately he bobbed upward like a cork. A reverse twirl sent him plummeting toward the bottom again. Bud, watching with wide-eyed excitement, began experimenting on his own.
Soon the boys were engaging in all sorts of underwater acrobatics. Presently Bud felt a nudge in the back that sent him hurtling a dozen yards through the water.
"Snuck up on me, eh, pal?" he thought with a chuckle. "Okay, Tom old boy, here's where the undersea terror strikes back!"
Swooping around to return the compliment, Bud gulped in surprise. Instead of his chum, he found himself face to face with a bottle-nosed dolphin!
"Good night!" Bud thought. "A porpoise! So you're the joker who nudged me!"
With a playful toss of its comical-looking snout, the porpoise swam off, as if inviting Bud to join in the fun and games. A whole school of the creatures cavorted into view.
"Okay! If you want to play!" Chuckling, Bud darted in pursuit, whacked the porpoise that had nudged him, and jetted off again. The porpoise gave chase, whistling and grunting audibly.
Tom joined in the fun, and soon a rollicking game of underwater tag was in full swing. The dolphins seemed as playful and mischievous as small children.
Twenty minutes later the boys surfaced and hauled themselves aboard. Both tore off their masks and flopped into the boat, shaking with laughter, surfacing and diving.
"What was so funny down there?" Zimby asked.
When Tom told him about the dolphins, he too burst into laughter. The porpoises rose into view and convoyed the launch all the way back to the island.
The boys were so jubilant over the performance of the new hydrolung gear that Tom decided to press his search for the Brungarian sea-prowlers immediately. Soon after lunch they took off in the Sea Hound and headed for the South Atlantic. Hank Sterling, Chow Winkler, and two crewmen accompanied the boys.
Dazzling afternoon sunshine sparkled over the sea when they reached the missile search area. Tom immediately contacted Art Wiltessa and the task-force ships. They had no new developments to report.
The young inventor gave orders to submerge. As soon as the seacopter touched bottom, Tom and Bud swam out through the air lock with their hydrolungs.
They probed about for half an hour, ranging farther and farther from the Sea Hound. Then Tom felt a touch on his arm. He turned and saw Bud pointing off excitedly to the right.
A strange submarine was moving slowly toward them!
The boys exchanged looks of fear through their face masks as the knifelike hull and conning tower of the submarine loomed gray and ghostly.
Was the sub Brungarian? And what was it up to? Were the two young skin divers about to be run down or kidnaped?
Or was its crew friendly?
"Better not chance it," Tom decided fast. He caught Bud's eye again and motioned upward with a jerk of his thumb. "Topside, pal!"
"Roger!" Bud's lips shaped the word silently behind his face mask.
In a twinkling both boys flicked their density controls and zoomed upward. The sub at once seemed to betray a hostile intent. It blew its tanks and planed upward in pursuit. But Tom and Bud easily pulled away. Their density units worked like magic, shooting them straight toward the surface.
"Wow!" Bud shoved back his face mask as they broke water. "That baby was after us and no mistake!"
Tom nodded, treading water. "Let's not stick around here, either! We'll soon have company again if we do!"
Bud did not argue. "Where to, skipper?"
In the fresh salt air, with the sunshine sparkling on the waves, it was hard to believe that an enemy submarine was hot on their trail. But both youths realized their peril was growing by the moment.
"Back toward the Sea Hound," Tom said, pointing north-northwest. "Submerge as we go!"
Bud circled his thumb and forefinger, then adjusted his mask, and the two boys plunged back in. On a sloping downward course, they sped along like undersea rockets, their ion jets functioning perfectly. Minutes later, they sighted the seacopter.
Hank waved to them through the cabin window as they glided past. The air lock opened speedily and the two boys entered. Both heaved sighs of relief when they were safely inside.
"Somethin' wrong?" Chow asked, sniffing trouble.
"A strange submarine," Tom reported. "Brungarian more than likely. It may be heading this way if they've tracked us."
"A sub?" Hank was startled. "We've picked up nothing on sonar!"
"Check again," Tom ordered.
The sonarman bent to his scope and Hank listened intently over the hydrophones. Neither could detect any sign of another craft.
"Probably the same one that fired on us the last time," Tom said grimly. "We'd better clear out before they take another pot shot at us."
Hank sent the Sea Hound zooming toward the surface while the boys changed quickly into slacks and T shirts. Then Tom took over the controls for the flight home.
"Brand my vitamin vittles! Are we just goin' to turn tail an' run every time them varmints come skulkin' around?" Chow fumed as the seacopter arrowed northward.
"Not if I can help it," Tom vowed. "But first I must figure out a way to make our own craft invisible, so to speak. It's the only way to protect our American crews, Chow, if we hope to do any secret digging for that lost missile."
"Want another suggestion, skipper?" Bud put in. "This one is about the hydrolung."
"Sure. Speak up."
"How about putting some sort of communications system into our hydrolung gear? If I hadn't been close enough to grab you when I spotted that sub, it might have been curtains, pal!"
"You're right," Tom agreed. "I'll get to work on it."
It was sunset when Fearing Island came into sight. The boys flew a Pigeon Special back to Enterprises, where Tom phoned a full report on the mystery sub to the Navy Department. Then the two chums drove to the Swift home for a late supper.
Phyl Newton was visiting Sandy that evening, but the girls displayed a marked coolness toward Tom and Bud. Instead of engaging in conversation, they retired to Sandy's room upstairs to play records, while Mrs. Swift served the boys a warmed-up but tasty meal of roast beef and mince pie.
"What's wrong? Are we repulsive or something?" Bud asked as they ate.
Tom shrugged, concentrating on a mouthful of roast beef. "Search me. We sure don't seem very popular with the girls tonight."
Mrs. Swift, overhearing their remarks in the kitchen, smiled but maintained a diplomatic silence.
Suddenly Bud slapped his forehead. "Good night! No wonder!"
Tom looked up with a grin of interest. "Well, what have we done?"
"It's what we haven't done, pal!" Bud retorted. "We had a date this afternoon, remember? That beach party and dance put on by Sandy and Phyl's school sorority!"
Tom gulped. "Oops! Boy, we really did pull a boner this time! I completely forgot!"
As they finished supper, the boys discussed various ways to make amends. Boxes of chocolates? Flowers? None of their ideas seemed to have the proper spark.
"We'll have to come up with something super," Bud said.
"Right!" Tom agreed. "Let's sleep on it and see if we can't dream up something by tomorrow morning that'll really wow them."
The next morning Tom had a flash of inspiration as he drove to the plant in his sports car. He hailed Bud at the first opportunity.
"I have it, pal! What say we stage an old-fashioned square dance Tuesday night at the yacht club on Lake Carlopa?"
Bud's eyes lighted up. "Hey, that's a great idea! We'll invite a whole gang, get Chow to handle the refreshments, and make it a real shindig!"
The boys shook hands enthusiastically. Eager to patch matters up as soon as possible, they invited Sandy and Phyl out to lunch that day. Over dessert, the boys announced their plans for a square dance.
"We—uh—realize we goofed yesterday on that beach party," Tom said sheepishly. "But we're hoping you'll give us another chance."
The girls looked at each other, their eyes twinkling, then burst into giggles.
"You're forgiven completely!" Phyl declared.
"Then it's a date?" Bud put in.
"You bet it's a date, and don't you forget it!" Sandy warned. "Phyl and I are going right over to Dorman's Department Store and pick out some cute outfits for the dance!"
Tom and Bud chuckled over the success of their scheme as they drove back to Enterprises. Later that afternoon a telephone call interrupted Tom as he worked in his lab on a sonic-communications system for the hydrolung apparatus.
"This is Lester Morris," said the voice at the other end of the line. The name did not register with Tom at first until his caller added, "I hear you're planning a square dance Tuesday night at the yacht club."
Suddenly Tom remembered. Lester Morris was a popular dance orchestra leader in and around Shopton. He was also much in demand as a square-dance caller and fiddler.
"That's right," Tom said with a chuckle. "News must travel fast. We just phoned invitations to our friends."
Morris asked if musicians had been hired for the evening. When Tom said No, his caller volunteered for the job, offering to provide a small combo of country-style players. His asking price sounded like a bargain rate, and Tom, knowing Morris's reputation, was only too glad to engage him.
"Lucky break, his calling," the young inventor thought as he hung up.
Bud was delighted to hear of the arrangement when he came into the laboratory a while later. The boys talked over their dance plans for a few moments, then Bud asked:
"How's our underwater talkie system coming?"
Tom scratched his jaw thoughtfully. "A bit tricky but not too difficult," he replied. "It's mostly a job of adapting the sonarphone arrangement from our Fat Man suits—in miniature."
A tiny mike, Tom explained, would be installed on the inside of each face mask, with its output feeding to a sonar transducer on the exterior. The receiving transducers would feed from amplifiers to earphones. The hookup would be powered by the solar battery in the hydrolung power unit, by connecting wires through the breathing tube.
"That's neat, Tom," Bud said. "Need any help?"
"You can mold us a pair of new face masks—big enough to cover the earphones," Tom suggested. He handed Bud a penciled sketch from the workbench, adding, "Then drill the holes for the mikes and earphones—the dimensions are there on the drawing. But watch it so you don't crack the plastic."
While Bud complied, Tom began assembling the tiny electronic parts. In two hours the gear was ready for testing.
Tom wiped his perspiring forehead and gave Bud a grin of satisfaction. "Go get your swim trunks, fly boy. Let's give it a tryout in the tank."
"Swell idea! Be back in a jiff!"
After a quick change, the boys strapped on the new hydrolung equipment. Before adjusting his face mask, Tom mentioned that he had inserted scrambling circuits into the communicators to foil any enemy eavesdroppers.
"If they do pick up anything, it'll sound like chop suey," Tom ended with a chuckle.
The boys submerged in the test tank and proceeded to give the new underwater communication system a thorough check-out. It worked perfectly. Ten minutes later Tom and Bud clambered out again, dripping wet but well satisfied.
They had just peeled off their masks when Chow came charging into the lab, with a crowd of workmen and technicians at his heels. The cook was wild-eyed with panic.
"What's wrong, Chow?" Tom asked in alarm.
A MAGNETIC KIDNAPING
"The space people or some enemy's invadin' us!" Chow shouted. "Take a squint through your telescope, boss! Brand my bazooka, they may be landin' any second!"
More people came streaming in, attracted by the chef's cries and gesticulations. Some were bewildered, a few frightened. Others were laughing, thinking the whole thing a joke. The scene was rapidly taking on the proportions of a riot!
"Whoa! Slow down, Chow!" Tom ordered, trying to make himself heard above the din.
"It—it's the truth, boss!" Chow stammered, mopping his brow with a huge red bandanna. "Why, sufferin' rattlesnakes, didn't I hear 'em spoutin' their space lingo with my own ears?"
"You heard what?" Bud said.
"Spoutin' space talk!" the cook repeated. "It come right over the loud-speaker in the galley! They was chitter-chatterin' plottin' to blow us all to smithereens!"
"That's a fact! We heard it, too!" one of the workmen chimed in.
Tom and Bud looked at each other blankly. Then suddenly Tom's eyes kindled with a dawning suspicion. Whirling around, he rushed over to inspect the public-address outlet on the wall.
Meanwhile, Mr. Swift had just driven in through the main gate of Enterprises. "What's going on?" he asked the guard at the gate, noting the excited hubbub around Tom's laboratory.
"Don't rightly know, sir," the guard replied. "I was wondering myself. I know it sounds crazy, but I thought I heard someone yelling there was going to be a space attack."
Mr. Swift's eyebrows lifted in amazement. Without further discussion, he stepped on the accelerator and sped off along the paved drive. Seconds later, his car braked to a stop near Tom Jr.'s private laboratory. The scientist jumped out and made his way through the milling crowd.
"What's going on?" Mr. Swift stared in astonishment at Tom and Bud, who were both doubled up with laughter.
"A scrambled radio alert, Dad," Tom gasped between chuckles. "Chow thought some Martian monsters were invading us, and sort of pushed the panic button."
The Texan blushed as Tom explained what had happened. Realizing Chow's embarrassment, Tom tried to make his mistake sound understandable.
Apparently the power line to the ion-drive control board had somehow picked up the boys' scrambled conversation underwater. The signal had been transferred by inductance in the wall wiring and amplified over the public-address system.
"Our wall mike was on," Tom added, "and it probably picked up some of the sound waves from the tank. Anyhow," he concluded, slapping the cook affectionately on the back, "I'm sure glad we have a wide-awake hombre like Chow in the outfit. It wouldn't be the first time he's saved our necks!"
Chow perked up, and the employees, reassured, returned to their jobs.
"I have some news of my own," Mr. Swift announced with a smile as the room cleared. "But I'm afraid it'll sound pretty tame compared to a space attack."
"Let's hear it, Dad," Tom said eagerly.
"I've been conducting some experiments with those space plants," the elder scientist said. "It looks as though they may prove to be a valuable nutritional source."
The plants, Mr. Swift went on, showed promise of producing enormous amounts of protein quickly and cheaply—enough to increase the world's food supply by a sizable margin. Moreover, he had isolated a vitamin in this protein not found in any of man's present foods.
"Doc Simpson has been working with me," Mr. Swift concluded. "He has been doing some experiments of his own with a vitamin extract from the space plants. He thinks it may prove highly beneficial to human beings."
Tom was thrilled, and even Bud realized that Mr. Swift's cautious report could well turn out to be of history-making importance.
"I'd say your news makes a phony space attack look pretty tame, Dad," Tom said, his eyes flashing enthusiastically. "With the earth's population increasing, this could be the answer to the food problem."
"Don't tell Chow," Bud added, "or we may find spaceburgers on the next menu!"
The Swifts chuckled. Chow's hobby of concocting weird dishes was a standing joke at Enterprises, and already had led to such dubious triumphs as armadillo stew and rattlesnake soup.
Monday morning Tom buckled down seriously to the job of designing an undetectable sub. His drawing board was littered with sketches and diagrams when the phone rang, breaking in on his thoughts. Tom answered it with a scowl of impatience. The caller was Lester Morris.
"Could you meet me at the yacht club to talk over the dance program?" Morris asked.
Tom hesitated. For Sandy's and Phyl's sakes he was eager to do everything possible to make the square dance a success. But on the other hand....
"I'm pretty busy today," Tom said. "But my sister and my friend Bud Barclay can tell you what we want—probably better than I can. Suppose I ask them to meet you there after lunch?"
There was a slight pause. "Very well," Morris agreed, although he sounded a bit annoyed.
After hanging up, Tom phoned Bud and asked him to keep the appointment. Bud was only too happy to oblige, jumping at the chance to take Sandy out to lunch beforehand.
At one o'clock the husky young pilot and his date strolled into the yacht club lounge. Lester Morris was nowhere in sight, so they sat down to wait. Twenty minutes later the musician still had not appeared.
"I hope he hasn't forgotten," Sandy said, glancing at her wrist watch.
"If he's a square-dance caller, his memory ought to be extra good," Bud joked. "Fine thing if he can't even remember the time of day!"
After waiting a while longer, Bud decided to telephone Morris's home. But at that moment a thin, seedy-looking man came into the lounge. His close-set eyes and loudly striped suit combined to give him a somewhat disreputable appearance.
"Good grief! Len Unger!" Sandy whispered. "What does he want with us?"
Unger was walking straight toward them. Both Bud and Sandy had met him occasionally around town and found him obnoxious.
"Sorry, but Morris got tied up," Unger informed them. "He sent me to talk to you."
Sandy's blue eyes met Bud's in a flicker of distaste, but she tried to conceal her feelings. "Please sit down," she invited Unger politely. "What square-dance numbers does Mr. Morris do?"
Len Unger shrugged. "You name 'em."
"But, my goodness," Sandy said, puzzled, "how do we know he'll have the squares I name?"
Unger stared at her as if he did not quite understand. "You mean, can he call off the dances you want? If he can't, I'll let you know."
"Does he do patter calls or singing calls?" Bud put in.
Again Unger hesitated, then said, "Both."
"Wonderful!" Sandy exclaimed gleefully. "I thought he only did singing calls." After a moment's thought, she went on, "Well, let's see. What about 'Birdie in the Cage'?... And 'The Gal from Arkansas' ... 'Uptown and Downtown'...."
Unger jotted the names on the back of an envelope. Pausing a moment, he remarked, "Guess your brother was too busy to make it today, eh, Miss Swift? What kind of ex-spearmints is he working on now?"
"I really couldn't say," Sandy replied coldly. She always made it a point not to discuss Tom Jr.'s or her father's research work with outsiders.
Unger persisted chattily, "I read where he handled that Jupiter probe shoot for the Navy."
"Let's get back to square dancing," snapped Bud. As he and Sandy finished planning the program, Len Unger continued to drop remarks and questions about "The Great Tom Swift" and his inventions. All prying queries were side-stepped.
As soon as possible Sandy and Bud cut short the conversation and left the yacht club. Unger's face wore an angry sneer as they walked out.
"What a creep!" Bud said, when he and Sandy were driving back in his red convertible.
Meanwhile, in his private laboratory at Enterprises, Tom was somewhat discouraged. He had tried several different experimental attacks on the problem of an undetectable submarine. None had worked out successfully.
"I thought that idea of a sonar-wave baffle might lead somewhere," he murmured, "but it looks as though I'm wrong."
Flopping down on a stool at his workbench, Tom cupped his chin in his hands. He was frowning, deep in thought, as the pudgy figure of Chow Winkler came into the laboratory.
"'Smatter, boss?" the cook inquired cheerfully. "Ain't your ole think box workin' today?"
"Doesn't seem to be," Tom confessed.
"Give it time, son. Tomorrow's another day," Chow said philosophically. "What you need is a haircut for the square dance."
Tom laughed in spite of himself. "Maybe you're right, Chow. Might help me think better."
Tom got off the stool and stretched out the kinks in his legs. He strolled outside with Chow, then scootered to the parking lot and hopped into his sleek, silver sports car.
A moment later he was whizzing off in the direction of Shopton. Nearing town, Tom turned off on a side-road short cut. He noticed in his mirror that a truck behind him also turned off.
"Really barreling along!" Tom thought. "If you're in such a hurry, the road's yours, pal."
He pulled over sharply, motioning the truck to pass. Instead, to Tom's surprise, it closed in straight behind him. The next moment, Tom saw a port open below the truck's hood and a strange-looking device pop out on a springlike steel cable.
It clamped magnetically to Tom's rear bumper! His car was caught like a fish on a line!
Tom stepped on the accelerator, trying to pull free. The truck at once swerved off the road, steering around a utility pole. As the cable tautened, there was a sickening screech of metal and the sports car was brought to a crashing halt!
Tom's head slammed against the side window. With a groan, the young inventor blacked out.
As he regained consciousness, Tom's eyes fluttered open. Sparks of pain shot through his head. A groan escaped his lips.
"Oo-o! What hit me?" Tom wondered.
He was lying on a sofa in a strange room. Someone was seated nearby, watching him. Tom tried to move his limbs and sit up. Then he discovered that his wrists and ankles were tied with sash cord.
"Better lie still, sonny boy," a gruff voice advised. "You ain't goin' nowhere."
The man who had spoken got up from his chair and came over to the sofa. He was of medium height, very muscular looking, with cold, glittering eyes. Rolled-up shirt sleeves revealed his powerful, hairy arms.
"Where am I?" Tom asked, suddenly remembering the events on the road before he blacked out. "And what's this all about?"
The man said with a mirthless grin, "You're a prisoner. And you're goin' to stay here until the cops let Dimitri Mirov go. It's up to you how fast they spring him."