This unauthorized tribute

Is based upon

the original TOM SWIFT JR. characters.




As of this printing,

copyright to

The New TOM SWIFT Jr. Adventures

is owned by




This edition privately printed by


















          AN EERIE LIGHT





“WHAT’S wrong, Bud? You look worried.”

“Worried, Tom? What’s to worry? Here you are, experimenting with something you know absolutely nothing about—something from another world! I’m just trying to stay awake.”

Tom Swift, slender and blond, smiled at the sarcastic retort from his powerfully built dark-haired friend, Bud Barclay. “That makes it all the more interesting!” he replied.

The two eighteen-year-old youths were in Tom’s shielded high-energy laboratory at Swift Enterprises, the sprawling research and development firm headed by the young inventor’s father.

“Suppose the thing blows up,” said Bud, staring doubtfully at an opaque tube which rested on a small table near the center of the well-equipped laboratory. The strange tube, about eight inches in diameter and four feet long, had been extracted from a remote-controlled space capsule sent by other-worldly beings with whom Tom had established a difficult and tentative communication by radio. Recently Tom had used his diving seacopter to recover the vessel’s sealed inner compartment, breaking open its outer hull in the process. From the fragments, he had been able to salvage this one component of the craft’s mechanism. Now he was determined to uncover its secrets.

Above the tube was a large complicated camera and alongside of it a black spherical device mounted in front of a cupped oval reflector.

“What’s that gadget?” Bud inquired curiously.

“Dad developed it,” Tom replied. “It’s a high-energy-wave generator he calls a generex machine. Remember when we found the space rocket? This Eye-Spy camera could penetrate every part of it except the opaque tubes running the length of the hull.”

“How could I forget?” Bud chuckled. “I’m still knocking seawater out of my ears! And since we came back you’ve talked about nothing else but working on this tube.”

Tom laughed. “Okay, chum, I plead guilty. We’re just lucky this segment pulled loose when the shell split into pieces—the rest of its ‘innards’ are as invulnerable as that meteor-missile our space friends first sent us. Now I want to find out if the radiation from the generex will affect the tube in such a way that the camera can penetrate it.”

“Okay, you’ve got me curious,” Bud said enthusiastically. “Let’s get started.”

The young inventor walked over to a metal locker, withdrew two antiradiation suits, and gave one to Bud. The boys put them on, and then each donned a helmet with a heavy lead-glass visor.

The elaborate preparations made Bud gulp. “You’re sure these suits will keep us from being fried?”

“Well, I don’t suppose anything is absolutely certain in a scientific experiment,” said Tom with a wink. “But seriously, the layers of Tomasite in these suits, and in the visors, should stop just about any form of radiation in its tracks. Remember, the basic formula for Tomasite originated with the space people themselves.”

Bud nodded, but thought to himself: Yeah, but those aliens could be made of lead and concrete for all we know!

Tom moved toward the table. “Ready?” he called.

“Fire away!”

Tom switched on the special apparatus and a buzzing sound replaced the quiet of the laboratory. Then he set the frequency control to half power and the two experimenters watched the tube closely.

It began to glow—first yellow, then blue, then white—until it reached such intensity that Tom and Bud had to turn away to keep from being blinded. Gradually the glare faded, leaving the laboratory bathed in a cold light. The material of the tube seemed to have turned transparent as glass, disclosing its inner radiance.

“You won’t even need the Eye-Spy camera to see what’s inside!” Bud declared in awe. “It’s lit-up like a neon tube. Is that some kind of gas in there?” He took two steps closer to the table, extending his outstretched hand into the eerie greenish glow.

But Tom had taken a few steps back and was looking away from Bud and the tube. A slight motion had caught his attention. A strange, creeping iridescence was slowly spreading over everything in the room. To Tom’s amazement, various objects in the room began to change shape. Metal implements and glass flasks seemed to be sagging and drooping under their own weight! The front of a large microelectronics console suddenly cracked and fell away like thin pasteboard, and weird colored sparks could be seen dancing and darting within the circuitry. “Wh-what’s happening?” Tom gasped.

Bud cried out over his rad-suit intercom. Tom whirled to face him, and his jaw dropped in horror.

Bud was holding his hand up in front of him, the hand he had extended toward the tube. The thick protective gauntlet was dissolving away like ice under a blowtorch!

Bud!” Tom cried. “Get away from the table!”

I can’t see!” Bud yelled, fear clutching his throat. At that moment Tom noticed that his own visor was turning black! He could no longer see the generex control panel clearly enough to safely switch off the machine! “We’ve got to get out of here!” he warned.

Briefly Tom assured Bud that he thought they would be all right if they left the laboratory immediately. “But I—I feel—so drowsy,” Bud said slowly.

“Don’t give in to it!” Tom urged, beginning to feel sleepy also. “We’re in trouble, Bud. Head for the door! These suits aren’t giving us enough protection! Get out of here fast!”

He grabbed Bud’s elbow and shoved him toward the lab door. Then, groping ahead, unable to see, Tom stumbled into a workbench and crashed to the floor. Desperately he crawled along until his hand touched the leg of the table holding the tube and generator. Fighting to stay awake, he pulled himself up, fumbled frantically for the power switch, and clicked it off.

Meanwhile, Bud had managed to make his way to the door. “Here’s—the—exit, Tom!” he called. “Follow—my—voice!”

“I’m right behind you. Go on out!” Tom commanded. But the words were for his pal’s benefit. Bud had forgotten that his voice, coming in via Tom’s suit intercom, gave no hint as to where the young flier was standing!

Crawling, Tom felt his way to the door, where powerful arms pulled him to his feet and slid the thick, radiation-resistant door panel shut behind him.

Tom and Bud staggered into the corridor. Tearing off his helmet, Tom hurried over to Bud who was leaning against a wall, visor in hand.

“Quick!” he ordered. “Come with me!” His eyes smarting, Bud followed Tom to a smaller laboratory located near the end of the long corridor. Here Tom had set up one of his recent inventions—a device to detect in a few moments the amount of radiation absorbed by human tissue.

Peeling away the top of Bud’s suit, Tom quickly attached four wires to Bud’s arms, which were connected to an intricate panel. He snapped on the device, adjusted a dial, and watched the pointer of the radiation indicator flicker to life.

“What’s the verdict?” Bud asked weakly, almost afraid to hear the answer. Had he been fatally exposed to radiation?

Tom smiled in relief. “Luckily you’re okay. You’ve only absorbed 150 milliroentgens and it takes about 450 before a fellow’s in trouble.”

Tom then tested his own body. Although he showed a slightly higher indication, it was still within the safe limit. “It’s fortunate we got out when we did.”

Bud, heaving a thankful sigh, brushed back a lock of black hair and turned to his friend with a grin. “You mean we won’t glow in the dark after all? So what was that all about, anyway?”

“I have no idea,” replied Tom, shaken and awestruck. “I never saw anything like it before. Obviously when the generex machine made the containing tube transparent to light, it also became transparent to some other kind of radiation emited by that gas. The way it ate right through our Tomasite sheathing… unbelievable!”

“Well, it sure made a believer out of me!” Bud quipped. “What’s next?”

“I’m going back to that lab, Bud.”

“No chance!” his friend exploded. “Have you lost your senses?”

“The radiation’s down by now,” replied Tom. “I must make certain the room isn’t dangerously contaminated, though.”

Bud groaned. “Well, genius boy, you’re the boss. But you’re not going alone. Lead on!’”

Tom extracted two fresh antiradiation suits from an equipment locker. The boys donned them and Bud picked up a hand-held radimeter to test for ambient radiation.

“We’d better take along some flashlamps with lead-glass light tubes,” Tom said. “You can bet that radiation has burned out the filaments in the regular bulbs. Probably ruined the overheads, too.”

Looking like spacemen in the protective suits, the boys walked down the corridor and entered the laboratory. They shone the flashlamp beams around and checked the radimeter.

“Hey!” Bud cried. “This place is still mighty ‘hot’! Look at this reading! Don’t you think we should get out?”

“We’ll be safe in these suits for a while,” Tom assured him. “The tube is opaque again and the destructive rays have stopped. But later we must wash this room down with a cadmium salts solution.”

Tom picked up a few samples of the metal objects and glass pieces which had changed shape under the radiation. “Let’s take a look at this stuff in the lab next door,” he said. “And, Bud, bring the opaque tube, will you?” The radimeter showed that the space device was not radioactive at all, strangely enough.

Switching off the lights, Bud followed his friend from the room. In the laboratory Tom made a careful examination of the misshapen samples and discovered that they had become extremely hard, as if compacted. “This whole thing is baffling,” he said. “I’m going to call in the radiation boys.”

As it was late on a Sunday afternoon, Swift Enterprises did not have a full technical staff at work. Nevertheless, after making several calls Tom had assembled enough technicians with the relevant expertise to help him determine the atomic structure of the opaque tube. After briefly making the tube transparent and radiant—this time by remote control in a sealed chamber—they were able, for the first time, to take photospectrometer readings of both the exterior and interior of the tube. They found that the luminous inner gas was unreadable, but the outer material contained a new isotope of silicon.

“This is wild stuff!” exclaimed one of the workers. “This isotope is unheard of here on earth!”

“Naturally. The tube wasn’t made on this earth,” Bud observed.

Silicon again,” mused Tom.

Bud raised an eyebrow. “What do you mean, genius boy?”

Tom rubbed his chin, as he often did when his mind was fully engaged. “Don’t you remember? The transparent glaze on the meteor-missile contained an unusual silicon compound that we couldn’t duplicate. And the propulsion field around the transport capsule affected glass—silicon—when it passed over Shopton. And now this.” He chuckled, recognizing the blank look on his friend’s face. “It’s fantastic,” he insisted. “Silicon has an atomic weight of 28 and has three known isotopes; the first with a weight of 28, the others 29 and 30. The isotope in this tube has a weight of 33!”

“Is it worth almost getting turned into a couple of human neon signs?” Bud asked, grinning.

Tom shrugged. “I don’t know yet. It’ll take a lot more research to find out the details.”

At that moment the phone rang and the young inventor reached for the receiver. Tom glanced at the phone’s ID panel. “Munford Trent,” he informed Bud. “He’s working in the office today.” Munford Trent was private secretary to Tom and his father, “What do you suppose he wants?”

Tom answered the phone. Then Bud saw his pal’s face sag in sheer disbelief. Tom hung up the receiver and turned to Bud wide-eyed.

“Tom! What is it?”

“Trent just got a phone call… “ replied Tom slowly.

“From who?”

The young inventor looked his friend square in the face. “From the dead!”














“OKAY, pal. Don’t tell me!”

Tom shook his head. “I’m not kidding you, Bud. Trent swears he just took a phone call from Craig Benson!”

“Craig Benson!” Bud Barclay repeated goggle-eyed. “But he’s—like you said.”

A longtime Swift employee and friend, Craig was a pilot who had left Enterprises for outside work as a private pilot-for-hire. More than two years previous, while working for a United Nations agency, he had crashed in central Africa. Though the wrecked plane had never been recovered despite an extensive search through the wild jungles and nearby mountains, he was presumed dead. Tom and Bud had attended his funeral service in New York City.

Tom’s astonishment was now replaced by cautious joy. “He’s alive!”

“Guess so,” Bud commented doubtfully. “Or at least he’s making phone calls. Man, what a story he must have!”

“Trent couldn’t locate me, and Craig offered to call back in fifteen minutes, which is about now,” said Tom. The boys continued to put away the experimental apparatus, and locked down the tube from space in a secure cubicle.

The phone rang again. A deep, pleasant voice said, “Hello, Tom? Surprised to hear from me?”

Surprised?” Tom shouted. “Craig, I can hardly― ”

“Yeah, yeah, that’s the usual reaction. Listen, Sci-Fi, I’m calling from your home. Just got here. I want to talk to you and your father.”

“Craig! It’s really you!” Tom exclaimed. “Bud and I will be there in less than half an hour. This is wonderful news.” Hanging up, he turned to Bud. “It’s Craig, all right. He always called me ‘Sci-Fi’.”

Bud gave a shout of laughter. “This is turning into one of those ‘what a day’ days!”

The sun was setting as the two friends set off for the Swift home in Bud’s convertible. A few minutes later they parked the car in the garage and strode across the lawn and through the magnetic alarm field which surrounded the house. Special coils built into their wristwatches allowed Tom and Bud to pass through without setting off the alarm system.

Inside the large, comfortable home, the boys were met by Tom’s father. The tall, distinguished-looking man, with twinkling blue eyes, was an older edition of the young inventor. Mr. Swift led the way into the library where Craig Benson was waiting. Craig, a tall, husky man of twenty-four, had light-brown hair and blue eyes which were accented by his deep tan.

“I’m really here in the flesh,” he said, grinning, as Tom and Bud greeted him with warm enthusiasm. Then he added soberly, “I came to see you as soon as I got to this country because I have a story that I think will astound you. I thought it best not to make contact by telephone from Africa, because… “ Here he paused. “Well, let me tell it right. I found something in the jungle I can’t understand, something you’ll certainly want to investigate.”

Before Tom could reply, his mother entered the library and announced that dinner was ready. She was a slim, attractive woman with sparkling eyes and a charming smile. “I’m sorry to interrupt you,” she added, “but would you mind continuing your discussion at dinner?—Oh, Craig, it’s so good to have you back with us!”

She led them to the dining room where Tom’s pretty seventeen-year-old sister, Sandy, who was a great favorite of Bud’s, was waiting. Like everyone else, she was overjoyed at the flier’s reappearance.

As soon as everyone had been seated and grace had been said, Damon Swift asked eagerly, “Now let’s hear your story, Craig!”

The pilot smiled. “Well, it concerns the greatest and strangest disappearing act in the history of the world!” Then he added with a broad grin, “And I don’t mean me!”

Did your plane crash, as everybody thought?” asked Sandy.

“Yes and no, Lo-Fi,” he answered. “As you know, I was on assignment for the UN’s Special Commission on the Repatriation of Refugees. What you didn’t know—I agreed to keep it confidential—was that I had been asked to take an unusual course to scope out any signs of guerrilla encampments in Borukundi.”

“Borukundi!” gasped Mrs. Swift.

“You mean where that awful general is in charge?” Sandy inquired. “It’s in the news all the time.”

“Yes, and it has been for years now,” said Benson.

Bud asked, “What awful general are we talking about? I get my news from TV.”

“He calls himself Supreme Commander Osa Kotto Boondah,” Craig explained. “He’s pretty much a typical tin-pot tyrant, out to settle old tribal scores and make a name for himself—and money for his cronies.”

“Same old story,” said Tom.

“Yes. He gets away with it because Borukundi isn’t exactly a country—it’s a region of about 3000 square miles tucked away where three countries come together. Naturally, they all claim it, and now and then they fight over it. So General Boondah is left to fill the vacuum, so to speak.”

Sandy grimaced. “I read that he eats his enemies!”

“He’s bad enough in reality without those rumors, which are spread by the very guys he’s supposed to have eaten,” Craig observed with a smile. “Anyway, Borukundi is mostly dense tropical jungle and marshland, with a few scattered mountains. I was flying low when something—probably a missile from a shoulder-mount launcher—tore right through my plane. Took out my radio, too. I was too low to eject, so I managed a ‘treetop landing’ as best I could, which wasn’t much.”

“Your plane was never found,” Mr. Swift put in.

“I’m not surprised,” said Craig. “Not much of it reached the ground in one piece, and I was quite a ways from my registered flightplan. But somehow I survived.”

“How’d you manage that?” Bud asked. “Tom and I get into wrecks all the time, and I could use some pointers.”

Benson laughed. “Get yourself rescued by some friendly natives. The local Maba tribe cared for me in one of their villages. But they were pretty much under siege by Boondah’s boys—no phone lines, no roads or airstrips, and a jungle full of guerilla mercenaries to keep the world from paying a visit. They had been forced to return to the impoverished lifestyle of their ancestors. Still, they had some medical supplies and nursed me very effectively.

“When I recovered,” Craig went on, “the Mabas wouldn’t let me leave.”

“I understand,” interrupted Sandy with enthusiasm. “Since you were still alive after falling from the sky, they considered you to be some sort of minor god!”

The Swifts and their guests smiled and Tom said, “Somehow I can’t see anybody worshipping old Craig here.”

“It wasn’t like that, Sandy,” Craig corrected her. “The Maba are poor, not primitive. The village used to have electricity a few wars ago. What they really had on their minds was the possibility that I might be a spy working for the General, who is of a rival tribe. So at first they kept a strict eye on me. But they tried to be good hosts and told me many tribal secrets. One concerned a nearby mountain that was taboo.”

The pilot described a religious ceremony he had been allowed to attend one night near a small, craggy mountain several miles from the village. Noticing that all the natives were bowing toward it in awe, Craig had looked up just in time to see a strange sight. “Some sort of gas was issuing from a crevice in the slope,” he said. “It glowed—literally glowed—with a weird greenish light!”

Tom was leaning forward, intrigued by the story. Everyone had stopped eating.

“It’s hard to describe what it looked like, or the way it made the whole mountainside shimmer with phosphorescence. The natives could tell me nothing about the gas,” said Craig, “except that it was the sign of the ancestral spirits who lived under the mountain. I had been in the village for a year and had recovered from my injuries, so I decided to try finding out what the phenomenon was. They had gradually stopped watching me so closely, so one night I managed to slip away and explore the mountain.”

“Did you find out what the gas was?” Tom asked.

“No. That’s the job I thought you’d take over. But it will be the most difficult thing you’ve ever attempted.”


Craig said he had salvaged an oxygen container from his wrecked plane to capture some of the gas for analysis. “And since it was a long hike, I took my water flask and an earthen jar containing some food.”

Craig told how he had waited hours for the gas to erupt, then had left all the containers at the crevice and gone off to a sheltered spot to sleep.

“In the morning I returned, but there was no sign of the containers, and no footprints near them but my own,” the pilot said. “I figured that they must have been disintegrated by the gas.”

“African black magic!” Sandy said excitedly.

Craig chuckled. “Seemed that way, Lo-Fi, I’ll admit. To make sure, I got other containers and tried the experiment again. This time I watched until the glowing gas did appear. Sure enough, the containers vanished—in an intense burst of white light. They just sort of melted away, from the outside in!”

“Sounds fantastic,” commented Mr. Swift.

Tom and Bud exchanged glances. Both were thinking of their experience in the laboratory. The objects there had begun to change shape. Would they have disappeared completely if the experiment had continued? And, Tom wondered, was an incredible phenomenon taking place under the mountain in Africa which produced a substance like the isotope-gas inside the tube he had received from another planet?

At this point in the story, the whole group adjourned to the library where Craig recounted the story of his forced leave-taking from the native village—because he had ignored the taboo—and the long, terrible ordeal of his trek back to civilization. Many months passed before he had been able to return to America.

“An amazing story,” Mr. Swift remarked, and Bud asked, “What does the mountain look like?”

“I have some pictures of it,” Craig replied, explaining that he had managed to save his camera from the plane wreck.

Eagerly the others glanced through the pictures he produced. Tom and his father noticed that the area around the mountain was totally without plant life and that all the closer shots were badly fogged. The two exchanged meaningful and worried glances.

“The gas you describe must be caused by some type of nuclear reaction,” Damon Swift said slowly. “Everything points to that—the vanishing containers, lack of plant life, and the fogged pictures.”

“Yes,” said Tom. His face grim, he turned to Craig and asked, “How long did you stay in the area of the glowing gas?”

The pilot seemed startled by the question. He frowned for a moment, then answered, “I must have been around there for a total of ten hours. Why?”

“We don’t want to alarm you,” Mr. Swift said, putting a hand on Craig’s shoulder, “but Tom and I have reason to think that you may have been exposed to some powerful radiation from that gas.”

He suggested that the young man go with Tom to the laboratory and submit to a test with the radiation detector. Craig readily agreed.

While he and Tom rushed to Enterprises, Mr. Swift phoned the home of the newly hired company physician, Dr. Simpson, and asked him to meet the two there. The youthful doctor arrived just as Tom finished attaching the wires of the detector to Craig’s arms.

Tom introduced the two men, then adjusted a control dial. The indicator flickered to life and the three stared at the pointer as it climbed to over 200 milliroentgens.

“You seem to have absorbed more than a moderate amount of radiation,” Dr. Simpson declared.

Craig paled and turned questioning eyes to the physician. “A fatal amount?” he asked.

“Not that, Craig,” the doctor said, smiling. “It’s not as serious as I may have made it sound. A few days’ rest, together with some medicinal treatments, should put you back in healthy shape.”

Whew!” Craig swallowed hard. “You had me scared for a minute!”

After Dr. Simpson had administered a treatment of chlorides to Craig in the company’s infirmary, he instructed Tom to see that his friend had plenty of rest and fresh air for at least a week.

Tom telephoned his mother to inquire if Craig might use the guest room at their home. “Of course,” she said warmly, “and how wonderful that he’s going to be all right!”

When Tom and Craig returned to the Swift home, the young pilot announced that there was more to his story.

“I must admit that I’m intrigued by it,” said Mr. Swift, as Tom and Craig sank deep into comfortable chairs.

“You were going to explain why you felt you couldn’t contact anyone by phone,” Bud reminded Craig.

“Ever since I reached civilization in Africa, I’ve had a feeling that I’m being followed,” the pilot began. “I lived in Bangui for a few months, mostly in a hospital recovering from an infection I’d picked up in my trek through the jungle; then I moved on to Libreville on the coast. There was nothing very significant I can put my finger on, but a few unexplained incidents.”

“Like what?” Tom prompted.

“In the hospital I was told that a man had inquired repeatedly as to when I would be released. From his description, I think he might have been another patient who shared a room with me for a few days when I first arrived, an English-speaking Nigerian named Leopold Mkeesa, who said he was a registered dealer in small arms.”

“Perhaps he was just showing a friendly interest, since he had become acquainted with you,” Tom’s mother commented.

“Oh, Mother, no one shows a ‘friendly interest’ over and over like that,” Sandy put in excitedly. “The man was probably a smuggler!”

“Were there other incidents?” asked Tom.

“Well, just as I was about to board the jetliner to return to the States, I was detained by the local police. Something about an anonymous phone call warning them that I was carrying ‘war diamonds’ out of the country. Luckily I managed to prove my innocence before departure time.

“Then on my flight two men seemed to go out of their way to make friends with me. They introduced themselves as Karl Taylor and Eric Cameron. They kept pumping me about my business in Africa—subtly, of course, but they were persistent enough to make me uneasy. Then, during the sleep period, I woke up to find Taylor tampering with the latch on my suitcase in the overhead bin!”

“What happened?” Tom asked.

“Naturally I asked Taylor what he wanted,” Craig replied. “Tom, he’s a smooth operator! He gave me such a convincing line about mistaking my suitcase for his in the dimmed light that I dropped the subject.”

“Did you see much of the men after that?” Tom queried.

“No. They kept to their seats. Then, after we landed, I didn’t see them again until yesterday when I arrived at Shopton. I’m positive I spotted Cameron in the bus station, but he vanished before I could hail him.”

Tom picked up a Shopton directory. Neither man was listed. “Of course, Cameron’s being here may not mean a thing, but just the same we’d better be on guard. I’ll alert our security chief, Harlan Ames. He’ll want you to describe these men.

“Taylor is about five feet nine, black hair― ” The pilot reached for a pencil and paper. “Maybe I can sketch a picture of him.”

“I didn’t know that you were an artist,” Tom commented.

“I’m not really,” Craig answered modestly. “But it’s fun for a hobby.”

After Craig had filled in a few further details, Tom described the strange experience he and Bud had had that afternoon and their suspicions that there might be a similarity between the mountain phenomenon and the contents of the opaque tube.

“This is amazing, Tom!” exclaimed Mr. Swift. “If Enterprises could locate the source of a silicon isotope not yet discovered on this earth, it would be a great boon to mankind.”

“And to the manufacture of rockets for interplanetary travel,” Tom added. He looked straight at his father. “If it wouldn’t interfere with our experiments here, I’d like to go to Africa at once, Dad.”

“I knew this would be coming.” Mr. Swift chuckled. “Go ahead, Tom!”

“Great!” Craig exclaimed. “I was hoping you would go there with me. Now that I’m officially alive again, I’m anxious to go back.”

“But what about the natives?” Mrs. Swift asked, concern in her voice. “They banished you, Craig.”

The pilot smiled. “I’m sure that we won’t have any trouble with the Maba—my rescuers. They’ll be impressed that I survived the taboo. But we might have a little opposition from a neighboring tribe known as the Onari. The General is one of them, and I wouldn’t want any of them for playmates!”

“Well, we’ll lick that problem when we get to Africa,” Tom commented. “The first step is to plan the expedition.”

Next morning the two young men ate a hearty breakfast, then walked to Swift Enterprises. Tom ushered Craig into the office he shared with his father. The pilot wandered around the spacious room, admiring the models of inventions by Tom and Mr. Swift that he had not seen before. He asked about the Sky Queen, Tom’s giant plane which could ascend vertically by jet lifters.

“It’s really a Flying Lab,” said Tom. “It’s what we’ll use for the trip to Africa. We won’t have in-flight movies, but the meals are top-notch!”

“And what kind of a submarine is this?” asked Craig. “It has an open part in the center with rotor blades in it.”

Tom smiled. “While in it, I found the rocket from another planet, but nearly lost my life doing it. You know, Craig, every time I start a new project, I can’t help wondering what adventures I’ll run into. Now take this African expedition― ”

Craig interrupted. “Say, speaking of food—how did that cowboy fellow work out, the one you and your Dad had just hired as a chef? Quite a colorful character, as I recall.”

“Chow? He’s everybody’s favorite around here.” Tom glanced at the wall clock. “Matter of fact, it’s about time for his mid-morning snack run.”

Sure enough, in a matter of minutes there came a loud and lazy knock on the door.

“Come in!” Tom called.

A balding roly-poly man, bronzed and wrinkled from the sun, strode into the office. Polished western boots flashed beneath the cuffs of his bluejeans and a garish plaid shirt in the southwestern style completed his outfit. Texas-born, formerly a chuck-wagon cook in New Mexico, Chow Winkler was now in charge of food on Tom’s expeditions.

“Howdy!” he shouted. “Oops! Didn’t know you had company— No, oh no! Cain’t be! But it sure is! Well, brand my lil lost palomino! Where’n creation did you come from, Craig Benson? You remember me?”

“Chow, it’s good to see you again. I finally escaped from that jungle cooking—crocodile stew with a few humans mixed in― ”

“You mean you been livin’ with cannibals?” the cook cried out. But Craig could not keep his face straight and Chow said, “At your ole jokin’ again, eh? Well, I sure am glad you’re back—but I had a Texas hunch you wuzzen as dead as they made out. But don’t fly over none of them jungles any more.”

Tom laughed. “Why, Chow, that wouldn’t worry you, would it?” he asked. “Craig and I are planning a trip to the African jungle and thought you’d like to come along.”

Chow scratched his broad, barren head. “Are you kiddin’, too, Tom?”

“Nope. Serious as Sunday.”

The cook sighed. “Where you go gallivantin’, I go too. But it sounds mighty risky. By the way, I jest rambled in to see if you wanted some o’ these― ” Chow’s eyes suddenly fell on one of the sketches Craig had made the night before. “Well, I’ll be hog-tied!” he blurted out. “Who drew these?”

“Craig,” Tom said.

“Mighty nice. Say, either of these hombres from Texas?”

“Why do you ask?” Tom queried.

“Jest thought I’d seen one of ’em before. This one here.”

“That’s Taylor,” Craig said. “Karl Taylor.”

“Don’t recollect the name.” The cook ran a ham-like hand through his sparse hair. “Not real sure where I saw him,” he murmured. “Mighta been Abilene, years back. Let me ponder it a bit. If I saw him, you kin bet I’ll remember.”

The remainder of the day was spent in preliminary preparations for the coming expedition. Tom and Craig studied charts of Central Africa provided by Enterprises’ geographical department and made a few tentative lists of equipment and supplies.

It was almost dark when they started on foot for the Swift home, glad of a walk in the fresh air.

“Since it’s so late,” Tom said, “let’s take the short cut I use through the lane in the woods.”

The two were striding briskly along the deserted dirt road when they heard the roar of a motor directly behind them. Tom and Craig whirled to see a car, without lights, approaching at terrific speed. The driver evidently did not see them.

“Look out!” Tom cried out.

Suddenly the car’s xenon-bright headlights blazed on, blinding Tom and Craig. The young men stared in frozen horror as the vehicle careened madly toward them on the narrow road!














THE APPROACHING lights seemed to have a hypnotic effect. It was only with difficulty that Tom was able to rouse himself to action. He pushed Craig into the roadside ditch and jumped for it himself. The car sped by, grazing Tom and spinning him painfully to the ground. Dirt and stones thrown up by the car’s wheels showered down on the two.

Dazed, Tom arose, brushed off the debris, and hobbled onto the road. “Craig!” he called. “You okay?”

“I—I guess so,” responded the pilot shakily. He stumbled from the ditch, muttering, “This is a great reception you folks have worked out.” He stood and looked off down the road. The car’s taillights had already disappeared. “Whoever was driving that car meant to kill us!”

Tom nodded grimly. “You’re right. I think there were two men in it. Did you spot the license number?”

Craig shook his head regretfully. “All I know is, it was a black Montserratti.” He added in a somber tone, “Tom, I feel that it’s because of me that you became a target.”

“Not necessarily, Craig. This sort of thing has happened to me before. Since you’ve been away, Bud and I have survived all sorts of dangerous situations.”

Benson snorted, with a wry smile. “And they say you scientists lead a quiet, academic life!”

Safely home, Tom contacted Harlan Ames and described the incident. “Looks like there’s more to this African business than we thought,” Ames observed. “As usual!”

The following morning it was decided that Craig should remain at the Swift home for a day of complete rest. Tom went off alone to one of his private laboratories, where he was soon joined by Bud, who had returned to Shopton late the night before from a purchasing trip, by jet to Atlanta.

“Good trip?” Tom asked.

“Got everything I went for.” Bud grinned. “Even those white pith helmets you wanted, jungle boy—just like they wear in the movies. But after you’ve made the discovery of the ages, yours probably won’t fit,” he gibed.

Tom pretended to throw a glass flask at him, then continued his work. Bud watched his friend sort an array of soupcan-sized, capsule-shaped objects which had just been delivered from Enterprises’ metallurgical department.

“They’re containers I had made up to get samples of that African gas,” Tom explained. “According to Craig, it disintegrated his crockery and metal bottles, but I’m hoping one of these more refractory capsules will hold the gas.”

He picked up a sheaf of papers from the workbench and handed them to Bud. “These are the specs on each of the containers—what material was used to make them and how. Read them off to me, please, and I’ll stamp the symbols on each one.”

“Right.” Bud began reading: “Heavy glass, lead, asbestalon—that plastic asbestos substitute of yours ought to do it.” He went on reading, “Tomasite—giving it another chance, huh?”

“I’m trying a different composite formulation,” Tom said. “Besides, it’s just a guess that the taboo mountain gas is similar to what we found in the tube from the rocket.”

Just then a buzzer sounded. “Somebody’s at the door,” Bud said. “I’ll get it.”

Reaching under the workbench, he pushed a switch that operated the locking device on the laboratory door. Hank Sterling, head of engineering at the plant, and Arvid Hanson, chief modelmaker and prototype fabricator, entered together.

“Hi, Tom, Bud! Sorry to disturb you,” said Hanson. The tall, big-boned man had a genial smile. “Hank and I have a few questions to ask about Terry.”

Bud smiled at Tom quizzically. “New employee? Or personal friend?”

Tom chuckled. “You haven’t met Terry, flyboy? I’ll introduce you right now.” From behind his workbench he lifted a plastic model into view.

“I had fun making that one,” Hanson commented.

Sterling said in an admiring tone, “I’d like one of those for Christmas!”

The model consisted of an elongated, flat, triangular platform, the wide part of the triangle at the front. At each of the three corners of the platform was an assemblage of rings intricately mounted one inside another and set at different angles to one another. About a third of the way back, a round turret rose up from the platform. A metal beam extended forward from this, resembling the arm of a crane and composed of a number of segments that telescoped together. Behind the turret base was a round-roofed passenger cabin.

The most arresting feature of Tom’s invention was its exploration cabin, which nestled snugly on the narrow aft end of the platform, in a cup-shaped framework cradle. Spherical, with two wide windows curving around its middle, the cabin was removable. When the crane was in operation, cables hanging from it would lift the cabin away from the chassis, swing it around to the front as the turret rotated, and raise or lower it as the cables unwound from a spool-drum.

“The terrasphere,” said Tom proudly. “Or if you’re on a first-name basis, Terry.”

“Pleased t’meet you,” said Bud. “When did you come up with this, Tom?”

“It’s the cave-explorer vehicle I’ve mentioned to you,” the young inventor replied.

“Tom said you called it the spelunker-clunker,” Hank said to Bud with mock severity.

“Yeah, well, that was before we were properly introduced. But I thought it was going to be more like a tank, genius boy.”

Tom nodded. “I got a few ideas along the way. For example, instead of tank treads, Terry has these tread-rings, as I call them. As you see, they’re like circular tread tracks, with each track being able to be swiveled to a different axis-angle independently of the others. That’s to give us extra traction and stability inside caves, where there’s usually a lot more wall than floor.”

“And this metal ball must be the terrasphere proper.”

“Right,” Tom confirmed. “The main vehicle can’t handle a sheer cliffside or steep drop. In such a case we’ll park her and lower the explorers in the sphere, which has its own air supply and power system.” Occupants of the cabin could safely explore and study deep chasms or caves which other vehicles could not penetrate, communicating with the tank section by means of intercom wires within the suspension cables.

“When Swift Construction said the terrasphere was finished, I decided to take it along to Africa,” Tom explained to Bud.

“Really? Don’t tell me those wheel-deals allow it to drive on top of the ocean!” boggled the young pilot.

“Believe it or not, Terry will fit in the aerial hold of the Queen when she’s all folded-down,” Arv said. “We’ll just have to leave the Kub behind.” The Kangaroo Kub was a midget jet plane that was normally carried along in the flying hangar of the giant skyship.

Turning to the men, Tom asked, “What seems to be the trouble, guys?”

“Arv’s miniature working model ran as perfectly as the computer simulations,” said square-jawed Hank Sterling. “But something must not have scaled-up quite properly. We’re not satisfied with the full-sized model. I’m worried that the locking device on the cables isn’t adequate.”

“You know how Hank worries,” gibed Arv.

“I’ll go down to the big hangar and take a look at it,” Tom said at once. “Come on, Bud. I’ll need your help.”

Taking Enterprises’ moving-rampway system, called the ridewalk, the boys accompanied the two men to the cavernous underground hangar beneath the main airfield. In addition to housing the Flying Lab, this hangar was the usual testing ground for large-sized inventions and housed an elaborate array of test equipment.

Next to the Sky Queen, in the center of the high-ceilinged main room, stood the polished gunmetal-gray terrasphere tank, firmly anchored to the concrete floor with giant expansion bolts. After Tom had thoroughly inspected the locking mechanism at the end of each cable, he announced that every part seemed to be in perfect working order.

“I want to give Terry a test, Bud,” he said. “I’ll climb into the sphere. You get into the control cabin and swing me back and forth. I want to put maximum stress on these cables and watch the signaling system.”

Bud climbed into the control compartment on the mobile platform, which was located at the top of the crane turret under a small view-dome. Tom entered the sphere through a round hatch. Then, after some practice at the controls under Hank’s supervision, Bud moved a joystick lever which lifted the crane from its horizontal position. He swiveled the boom and began to extend it, and in a moment the descent cabin was dangling at the end of its reinforced cables several feet off the concrete floor. “Ready for your ride?” he called to Tom over the intercom.

Tom gave Bud some instructions and then said jauntily, “Swing away!”

Tom watched the gauges on the panel in front of him, which indicated the amount of strain on each cable. As Bud swung the crane from side to side with increasing vigor, the young inventor felt as if he were being rocked.

“This is smooth and working in perfect rhythm,” he said to himself.

Elated, the young inventor grinned and waved to Hanson and Sterling.

“How do you like it, Skipper?” Bud intercommed.

“Like a carnival ride,” was Tom’s reply. But as he turned back to look at the gauges, the grin faded. One of the dials was flashing a red signal. There was too much stress on cable number three!

“Bud, hoist me back onto the cradle!” Tom yelled into the intercom.

At the same instant every light on the panel blinked red. This was followed by a loud twang as the cables parted just above the locking device. The cabin broke loose and was hurled into the air like an underhand pitch, then somersaulted to a crash landing against one wall of the hangar!

Bud dashed from the control cabin, fear gripping him.

Sterling and Hanson had already reached the sphere. Through a window they could see Tom lying unconscious against the panel board. Blood streamed from a gash in his head.

Working quickly, the men opened the hatch and carefully lifted Tom out and laid him on the floor. Bud leaned over him. When he was certain that his friend was still alive, he raced to an adjoining room for a first-aid kit and administered a restorative. A minute later the young inventor opened his eyes.

“Take it easy,” Sterling cautioned him. “You had a nasty crack-up.”

Tom lay still for a minute. Then, as his memory returned, he smiled ruefully. “It was my fault,” he confessed. “Swinging so violently must have crystallized the cables at the connection, and they gave way.” Starting to rise, he said, “I’ve got to get busy and make cables which will be less subject to metal fatigue.”

“Not today,” Bud told him firmly. “You’re going home to relax—Sci-Fi.”

He drove Tom to the Swift residence where Sandy and her mother took charge. Both gave sighs of relief when they learned he had escaped serious injury.

Craig, looking on, finally broke the tense atmosphere by remarking, “Welcome to the club, Tom! There’s no feeling on earth like being able to walk away from a major smack-down!”

Late that afternoon a telephone call came to Tom from Harlan Ames. Tom took it on the extension in his bedroom. After the security chief had made sure Tom was recovering nicely from his shock, he said, “The local police have just recovered a stolen car—a black Montserratti. It could be the one that almost ran you and Craig down.”

“Any clue to the thief?”

“None,” Ames replied. “They forced open the door of the car and disabled the security system. No fingerprints except the owner’s.”

“Have you done any checking on those men Craig described—Taylor and Cameron?” Tom asked.

“I sent copies of the sketches to the FBI in Washington,” Ames reported. “I’ll let you know the minute I get a report.”

After the security chief had hung up, Tom sat on his bed for a moment in deep thought. If Taylor and Cameron had been the attackers in the car, what was their motive? And why would they be shadowing Craig?

Heavy footsteps pounded on the stairs and Chow rushed into Tom’s room excitedly. “Brand my cowhide boots!” he cried out. “I got it!”

Tom gazed at the cook in astonishment. “Steady there, cowpoke. Tell me slowly what you’ve got.’’

“Remember the picture you showed me o’ that feller Taylor? He’s from my own ranch country in Texas!”

“Are you sure?” Tom demanded.

“Sure as I am o’ tamin’ a mustang!” Chow insisted. “I recollect the very newspaper back home showin’ his picture. Seems he got in bad with the folks ’round there. Shady doings o’ some kind.”

“Is his name really Taylor?” Tom asked.

Chow shook his head. “I don’t reckon ’tis, but I cain’t remember what he was called.”

“What newspaper was his picture in?”

“The Comanche Daily.”

Perfect!” said Tom. “We can check with their office.’’

“Don’t think you kin,” the Texan murmured. “The Daily’s whole place burnt down ’bout a week later! They say it was set!”

“This is not news I can use,” Tom sighed. “Any idea where Taylor might have gone?”

“Well, some folks said they knew where he lit out to.’’

“Where was that?”















AT CHOW’S startling announcement Tom whistled in surprise and reached broadly to thump the Texan on the back. “Good work, Chow! This ties in with Craig’s suspicion that Taylor and Cameron had more than a passing interest in his African adventures.”

“I’m sure glad I remembered ’bout that hombre,” said the cook proudly. Then Chow hesitated, as if he had something more to bring up. “I did good, di’n’t I, boss?”

“Sure you did.”

“Wa-al, then I have sumpin’ to ask you.”

Tom nodded. “Anything, pardner.”

“You may wish’t ya hadn’t said that when you hear what’s caught in my craw,” the Texan said wryly. “It’s like this. You know how ya let folks name some o’ them inventions o’ your’n?”

The young inventor regarded his friend in puzzlement. “What do you mean?”

Chow shuffled his feet, embarrassed. “Aw, not much. Jest that you let Hanson name that Spacelane Brain, and buddy boy came up with Eye-Spy camera—other stuff, too.”

Tom nodded. “Yes, but—those are just nicknames we use.”

“I know, Tom, but… I’d like t’name one of ’em myself!”

So as not to injure Chow’s feelings, Tom suppressed the laugh he felt rising within. “I see. Well, which invention do you want to name?”

“Oh, I’m not too partic’lar. You can jest tag it on the next one that fits!”

“Y-you mean… you’ve made up a name in advance?”

“Sure have, boss. Got it writ down right here.” He fished around in his shirt pocket. “See, I know how you go about it, makin’ up them names. You take a buncha scientific soundin’ words from Greek or Latin an’ break ’em apart, then glue ’em back tergether, so t’speak. I allus figgered you did it that way to get inspiration. Am I right?”

“Well, I― ”

“Sure ’nough, thet’s the secret all right. So I come up with a couple names—but I’ll be satistated if you use jest one.”

Tom sat down on his bed. “Okay, Chow. What do you have?”

Chow held two pieces of paper between his thick fingers. He read off the first one. “How d’ya like ‘thermo-emetic quasartron’?”

Tom’s brow furrowed. How do I get out of this? he wondered. “I’m not… sure I can do too much with that one.”

“Then it’s the other fer sure!” He handed Tom the other slip of paper. “I kinda thought it’d be this one.”

Tom read it and nodded. “I’ll pin it up near my workbench. And I guarantee you, next time I invent something that could conceivably be called a, er, ‘spectralmarine selector,’ that’s what it’ll be.”

Chow beamed a broad Texas-sized grin. “That’s what I wanna hear! Ya promise?”

Tom laughed, finally. “Promise!”

Chow began to leave, then glanced back over his shoulder. “Oh, an’ boss? It’s spectro-marine. Spectral-marine sounds a mite foolish!”

Later, when Tom and Craig were lounging in the Swifts’ guest room, Tom told the pilot of Chow’s verdict on the man Craig knew as Taylor.

“Then I was right about Taylor all the time!” Craig exclaimed.

“Can you think of some reason he may be trying to keep us from going to Africa?” Tom injected.

“No. But I believe you’re right. It may have to do with that Nigerian, Leopold Mkeesa. Why don’t we have Taylor picked up?”

“On what charge?” Tom pointed out. “We haven’t a shred of proof that he was in that automobile. In fact, we can’t even say for sure he’s here in Shopton.”

“But I’m certain that I saw Cameron in Shopton, so it’s likely Taylor’s here too,” the pilot protested. “Anyway, if Taylor was involved in something shady and skipped the country, he must be wanted by the authorities.”

“Yes, but the name Taylor is probably an alias,” observed Tom. “If it weren’t for your sketches, we wouldn’t know whom to look for. We’ll have to be patient. If Taylor and Cameron are trying to cause us trouble, they’ll show their hands sooner or later.’’

The next few days passed without any indication that their suspected enemies still were in the vicinity. Tom pushed the outfitting of the terrasphere for its use in the Africa project. He personally supervised the fabrication of new cables of great tensile strength. As a further precaution, these were X-rayed for flaws before being installed.

Early one morning Tom said to Craig, “We’ll be ready to take off in the Sky Queen pretty soon. Want to help me inspect her?”

“Sure thing, if there’s no charge for admission,” he replied jokingly.

The two went to the underground hangar where the Flying Lab was berthed. Craig gazed in admiration at the three-decker plane. “It’s beautiful, Tom. Almost overwhelming!”

Tom led the way on the tour of inspection, which began with the laboratory section. This was on the second deck. Partitions divided the spacious enclosure into separate compartments. Each was a laboratory completely equipped for some branch of research.

“This is a world all its own,” Craig remarked.

“The Sky Queen,” commented the young inventor as they walked along, “is like an old and loyal friend. She’s carried Bud and me safely through many a tough adventure.”

Craig congratulated Tom on the sleek Kangaroo Kub, a small delta-winged craft, powered by a single jet engine, which was berthed in the Flying Lab’s aerial hangar on the lowest deck. “We’ll be leaving the Kub behind to make room for the terrasphere tank,” Tom explained.

“There’s sure plenty of room in the flying hangar, even with the mini-jet!”

“We used to carry another small craft as well, the Skeeter. But it was wrecked.” Tom added: “I have another one on the drawing boards, though.”

As the inspection ended and the three young men were about to leave the building, they were met by Mr. Swift. After greeting them, he said, “Tom, I’d like to discuss with you that series of experiments we conducted together in New Mexico, Project XA-107. We’ll get out the file and go over it.”

Tom looked at his father curiously. “Do you mean the one on antiproton phenomena, Dad?”

“That’s right. I’d like to review our findings.”

“Any particular reason?” asked the young scientist.

“Just a hunch, son. From what Craig has told us about that glowing gas in Africa, I was wondering― ”

“If it might have something to do with the existence of antiproton matter under the mountain?” Tom finished the sentence. “I was thinking about that possibility myself.”

“If such a thing exists there, our locating it would be one of the greatest discoveries of all time.”

Craig, who had been listening quietly to the discussion, displayed a puzzled expression. “Is this a family secret?” he asked, smiling, “Or may I join in with a question?”

“Sorry,” Tom apologized. “Ask away.”

“First of all,” said Craig, “what’s antiproton matter?”

“To explain that,” said Mr. Swift, “you’d need a basic idea of how atoms are constructed.”

“I didn’t flunk all my high-school science,” Craig replied in joking protest. “I know that the popular concept of an atom is that it looks like a miniature solar system. In the center is a nucleus. Moving around it are particles called electrons. The whole thing is similar to our own planets moving around the sun.”

“That’s basically it.” Mr. Swift nodded. “An electron has a negative charge. A proton is the positive charge of the nucleus. Then we have the neutron, which is the uncharged remainder of the nucleus.”

“That much I understand,” said Craig.

“Now in antiproton matter,” Tom took up the story, “the atoms have the same ‘solar system’ setup you mentioned, but there’s one difference. The charges on the particles are reversed. What was the negative electron is now a positive positron—an anti-electron, that is—and what was the proton is now an antiproton, which has a negative charge.”

“Oh, you’re talking about antimatter,” Craig said. “Bring matter and antimatter together and Blam!”

Definitely!” Mr. Swift broke in. “If enough antiproton matter reacted with substances here on earth, the heat produced could start a chain reaction. The world would blow itself into oblivion!”

“Wow!” exclaimed Craig. “That stuff wouldn’t be anything to play with!”

“No,” Tom agreed, “but actually it could be put to good use. In fact, some radioactive isotopes emit positrons naturally, and PET scanners—the letters stand for Positron Emission Tomography—have become a standard part of medical technology.”

“Antiproton matter is another story, though,” declared Mr. Swift. “There’s an enormous difference in mass, and thus an enormous difference in explosive energy when proton meets antiproton. I can’t conceive, scientifically, how stable antiproton matter could manage to exist on earth.”

“Want my guess, Dad? I think Craig’s gas isn’t antiproton matter as such, but some weird substance that emits free antiprotons at high velocity,” speculated Tom. “If the gas itself were true antimatter, it would react explosively to air.”

The animated discussion continued as the three walked along toward the main administration building. Tom declared, “I think we may be on the verge of a whole new twenty-first century physics, Dad. We seem to be running into more and more inexplicable things—veranium ore, for example, or that micro-sized black hole Bud and I encountered in space.”

“Yes, son; and also those signs of higher-element fusion going on beneath the crust of the earth, which you discovered with your atomic earth blaster.”

“I guess it’s kind of a whole new world out there,” said Craig thoughtfully. “And that crack in the taboo mountain may be the front door!”

When the group reached the office building, Craig said goodbye and Tom followed his father inside. They went directly to their private office where the young inventor slid open a wooden panel in the wall. Behind it was a small but sturdy safe. He pressed his knuckle against a scanning device which read his recorded DNA code, and the formidable lock clicked open.

Tom reached inside and withdrew a stack of leather-bound manuscripts. After going completely through the pile, he stared at the stack curiously.

Mr. Swift sensed that something was wrong. “What’s the matter, son?”

“It’s gone!” Tom cried out. “The file on antiprotons is gone!”

“Great Scott!” exclaimed the elder inventor, stunned. “This is terribly serious. The weapons potential of antiproton applications is cataclysmic!”

“I can’t imagine how it disappeared,” Tom mused. “The only other person who has access to this safe is Alvy Tompkin.”

“Tompkin wouldn’t be interested in our treatise,” said Mr. Swift. “He’s as trustworthy as you or I, Tom. He’s been with us Swifts since the day Enterprises was formed!” Tompkin had been transferred from the Swift Construction Company and made special guardian of the office a few months before.

“Just the same,” said Tom, “it won’t do any harm to ask him if he knows anything about the manuscript.”

Tom summoned Alvy Tompkin to the office over the intercommunication system. A few minutes later a thin, elderly man came in. His strong face and direct gaze reflected his integrity.

“Tom and I are hunting for something we can’t find,” Mr. Swift said. “We thought we left an important file, Project XA-107, in the safe. Do you remember seeing it there?”

“Yes, of course I do,” replied Tompkin, but with a puzzled look. “It was only yesterday, Tom, that I took it from the safe. I was only following your orders.”

“Orders!” Tom exclaimed. “What orders?”

“Your note, from the office digi-fax.” From a pocket Tompkin produced a typed note bearing Tom’s signature.





“You say you received this over the office digi-fax?” Tom asked. “I never wrote it.”

Tompkin turned ash white. “But Tom—Mr. Swift—I recognized your signature!”

“I’m not blaming you, Mr. Tompkin,” said Tom in a comforting tone. “You had no reason to suspect that the signature might have been forged.”

“I—I suppose I should have telephoned you for confirmation,” moaned Tompkin in despair.

Tom asked for a description of the man who received the file.

Tompkin thought for a moment, then said, “He was about six feet tall, had black hair, a thin face, and very dark eyes. He was driving a light-blue sports car. I’m afraid I didn’t pay attention to the make.”

Tom showed the elderly employee copies of the two sketches Craig Benson had made. “Was he either of these two men?” he asked.

Tompkin studied the drawings, then pointed. “Yes,” he muttered, “it was this man. He wore dark glasses, but I’m quite sure of it.”

Tom glanced at his father.

“Cameron!” Mr. Swift cried out.














DISMISSING the remorseful Tompkin, Tom and his father contacted Harlan Ames at once and the security chief came to the office immediately. He sat down and Tom briefed him on what had happened, then showed Ames the fake note. After the former Secret Service agent had scrutinized the signature closely, he commented, “The forgery of the signature has the earmarks of a real pro.” Ames pointed out several ways in which the forger had avoided common errors. “At least we know a little more about Taylor and Cameron. Probably one of them is an expert forger.”

“It didn’t take any fancy electronics to get under our skin this time,” Tom said angrily, “But it worked.”

“We can’t be prepared for every contingency,” Ames commented. “I think I’ll contact that FBI man we worked with on the Verano matter, Hal Brenner.” He arose. “See you all later.”

That evening little was said at the Swifts’ dinner table. Though Bud, usually a fount of vivid verbiage, had joined the table, everyone was unusually quiet. As Tom sat pondering the loss of the important manuscript, Sandy looked at her brother. “How valuable are those papers?” she asked.

“In the wrong hands,” he replied, “the information could affect the welfare of the entire world. Dad’s and my experiments were not complete by any means, but the file summarized some of the latest theorizing, and now that I think of it, it also speculated about possible methods of shielding against antiproton matter. I’d guess Cameron suspects that there is an antiproton gas in Africa.”

Craig spoke up. “I think I can figure out the chain of events. Leopold Mkeesa learned about the taboo mountain phenomenon from me, then hired the two men from the underworld contacts he must have made over the years.”

“You mean you told Mkeesa all about the taboo mountain?” Bud asked.

“I didn’t think I had,” replied the pilot. “But when I first arrived at the hospital, I was in pretty bad shape from fever and infection. I don’t think I can remember everything I did and said. And I don’t imagine ‘John Mueller’ is Cameron’s real name, any more than ‘Cameron’ is.”

“There’s one thing we mustn’t forget,” cautioned Tom’s mother, with a searching look at her husband and son. “You’ll be going to a part of the world claimed by a violent, ruthless dictator. He may already know of the mountain, and will be trying to do whatever it takes to keep it under his control.”

“That’s true, Mom,” Tom conceded. “General Boondah might be behind these events in some way.”

At that moment the telephone began to ring. Tom excused himself and answered it.

Chow’s voice came booming out of the receiver. “Tom Swift!” he shouted. “That you?”

“What’s up, Chow?”

“Stay put!” commanded the cook. “I’ll be over as fast as my gas buggy’ll fetch me there.”

Before Tom could reply, Chow had hung up.

Several minutes later a small, rust-laden pickup truck came bounding up the Swifts’ driveway and skidded to an abrupt halt. Chow leapt out and rushed up the front steps.

“Tom!” he boomed, as he came into the living room where the others had assembled, “Tompkin told me ’bout that forgery, so I reckoned it was time fer action!”


“I called an old amigo o’ mine from the ranch, a feller with a mem’ry like a steel girdle. He remembered that newspaper story, and what folks had been sayin’ back then about that dude—the one who calls hisself Taylor. Only his brand ain’t Taylor. It’s Harry Hoplin!”

“You mean it?”

“Brand my prairie dog, I sure never was more certain! Listen, folks. That sneakin’ critter was wanted back in Texas fer forgery!”

That’s the magic word, all right!” Bud exclaimed.

“An’ brand my bakin’ powder, that ain’t the half of it neither. After he hightailed it out o’ Texas, word got around that he ’as wanted fer other things, too—like murder! Boss, that cayuse is a bad one all round!”

Without a moment’s hesitation Tom went to telephone Harlan Ames. The security chief should be apprised of the fact that Taylor’s real name was possibly Hoplin and that he was a wanted forger! But Ames’s daughter told Tom that he was not at home—he was out seeking leads on finding the suspect.

Tom sat thinking for several moments. As soon as the thief realized that the local police were looking for him, he probably would skip out. “If he could only be located before he learns the authorities are after him― ” Tom reflected.

Jumping up suddenly from the telephone chair, he rushed back to the living room and told the others his thoughts. “I believe that the more people who join the search, the better,” he concluded. “Come on, Bud. Let’s go on a hunt for Hoplin ourselves!”

“I’ll go too,” Mr. Swift decided, and went for his car keys.

Chow loyally offered his services, and Sandy declared that she would pick up her friend Bashalli and join the hunt as well.

Mrs. Swift began a motherly protest: “Now Sandra, dear, there’s no point in― ”

“Mother, it’s not dangerous—we’re just going to drive around and see if we catch sight of him somewhere,” Sandy interrupted. “And besides—I’m a Swift!”

“You sure are!” nodded Sandy’s mother. “And so am I—which is why I’ll be joining you and Bashi in the car.”

“You can’t leave me out of this hunt,” said Craig, starting after the others.

“Wait!” Tom protested. “You’d better stay here, Craig.”

“Why?” asked the flier. “Doc Simpson told me I was all right.”

“I realize that,” he replied, “but he also advised you not to exert yourself for another week. Do it as a favor, okay?”

Craig, disappointed, watched the mob hurry from the house. It was decided that Mr. Swift would take the large family sedan, Bud and Tom would take Bud’s convertible, the women would use Tom’s own sports car, leaving Chow with his pickup truck.

“And let’s maintain ‘radio silence’ on our cellphones, unless there’s a real emergency,” Tom urged. “Hoplin probably has people listening in, and we don’t want to alert him.” The several cars then worked out which areas of Shopton they would each cover.

As Tom took the wheel of the scarlet convertible, Bud said, “Where do we start?”

Tom surmised that all the surrounding areas, except the locale of the Swift home, which sat at the edge of a large suburban wooded area, would be avoided by Hoplin in order to stay clear of the Shopton police and out of the public eye. “We’ll let the others cover those places. Our best bet,” he said, “would be to search right here, close to home.”

“Sure,” Bud nodded. “I have an idea those men are watching every move we make. Let’s smoke ’em out!”

They cruised around the tree-arched roads near the house, which of course were also in close proximity to Swift Enterprises. As the family had eaten an early supper it was still a bright twilight, and easy to see. Nothing suspicious was revealed. Minutes stretched into an hour, and the shadows lengthened. Soon the youths found themselves back in the vicinity of the house.

“One more road,” said Tom as he turned the car into a little-used rural lane. “We’ll drive through here,” he announced. “If we don’t find anybody, I suggest we go back to the house and check to see if there’s any report from the police.”

“Getting dark now,” Bud complained. “We could use night-vision goggles.” Having strained his eyes, Bud slumped back for a moment to rest. Then, suddenly, he sat upright. “Tom!” he called. “Swing our lights around to nine o’clock low!”

Tom spun the nose of the convertible to the left side of the lane and angled the narrow shafts of light in the direction indicated. The glare revealed a man loping across a small clearing. No longer hidden by the deepening night, he bolted toward a heavy cluster of trees and brush.

“He looks like Hoplin!” Tom cried out.

Killing the ignition, he leapt from the car, with Bud following. They lost sight of the suspect when he got out of range of the lights, but they could hear him crashing through the thickets just ahead.

The boys whipped out flashlights and raced after the man. The woods became more dense the farther they went.

Whoop!” Bud tripped and tumbled down a shallow ravine. Stunned but unhurt, he scrambled to his feet. Tom stopped to make sure that his friend was all right.

“Never mind me!” Bud shouted. “Keep after that guy!”

But the slight delay had been costly. Now the flashlights no longer picked up the fugitive. The boys forged ahead for some distance, but Hoplin had disappeared.

“It’s no use looking any more,” Tom admitted in disgust. “I’m afraid that we lost this round, Bud. But it proves one thing. Hoplin is still in the neighborhood.”

Fatigued by the wild chase, he and Bud trudged out of the woods and back toward the car. But before they reached it, Tom grabbed his pal’s arm and whispered, “Look over there—through those trees!”

As they approached the break in the trees, Bud could see what Tom had caught sight of—fresh-looking footprints in the soft earth and pine needles!

“This must be where our boy came through just before we saw him,” Bud said softly. “We can backtrack him.”

Caught up in the excitement of the chase, Bud began sweeping the ground with his flashlight. “I see more footprints!”

Tom examined them. “There was a meeting here involving three men!” he said excitedly. “Hoplin, the one who calls himself Cameron, probably, and somebody else as well.”

The boys followed the footprints for a short distance around a bend. Then the three sets of tracks became only two.

“One of them must have climbed down from the road, across those rocks,” Bud suggested. “But where did the other two start from?”

Tom led the way, his eyes straining for signs of a camp or cabin. A few minutes later he halted abruptly. Just ahead, nestled in a cluster of pine trees, was a small vacation cabin made of prefabricated logs. This could be the spot they sought! Tom gestured to his companion to crouch down.

“That building,” he said, pointing, “must be where Hoplin and one of his cronies have been living. Let’s get as close to it as we can without making any noise.”

The young scientist crawled, Indian fashion, in the direction of the cabin. Bud followed. The two pushed their way quietly to the edge of a clearing which fronted the log structure, and listened. Everything was still and dark.

“Shall we rush the place?” Bud whispered. Then, answering his own question: “We’d get caught if there are guards watching from the woods.”

“Right,” Tom agreed. “Let’s try smoking out anybody who’s watching for us.

“How?” the dark-haired flier asked.

Tom suggested that they each find a small rock and heave it, Bud to the right and Tom straight at the cabin. After locating round, good-sized stones and tossing them, the trio waited alertly, but there was no response to their strategy.

“Guess there’s no one inside,” said Bud. “If there were anyone else, he’d have come out—or at least ruffled those window curtains. Let’s investigate!”

Tom cautiously led the way to the cabin and peered through a window, trying to see through the curtains. But the utter darkness inside defeated him.

“I can’t see a thing,” he muttered to Bud. “But I’m sure no one’s home. Let’s try the door.”

Tom approached the door to the cabin and cautiously twisted the knob.

The next instant the woods thundered to a violent roar!














THE BLAST had come from inside the cabin. It blew the door to kindling and splinters, propelling Tom backwards into Bud. They both lay in a heap on the ground, unconscious.

Meanwhile the interior of the small structure began to flicker with orange light. Fire! Licking the fragments of the shattered door, the flames crept out into the open, igniting the weeds and dried brush.

Tom was the first to revive. He rolled off his pal and struggled to his feet, coughing in the smoke, wincing from the heat.

“Bud!” he choked. “Get up!” Kneeling, he shook Bud vigorously, and the youth’s gray eyes flickered open.

“Tom, is something on fire?”

“Come on, help me!”

The two of them managed to stomp out the fire in the brush before it had spread. The fire in the cabin seemed to be slowly dying away of its own accord.

“The door must’ve been booby-trapped!” Bud exclaimed furiously.

“No,” responded Tom. “Didn’t you hear the glass breaking just before the explosion? Somebody pitched a grenade into the cabin!”

“Hoplin must have circled back,” Bud muttered. “We still could’ve wound up dead!”

That I agree with!” declared the young inventor. Then he groaned—he was beginning to feel the pain of his bruises and burns.

“Let’s call the Fire Department and the Shopton PD from the car,” Tom said, “and then head for home.”

At the Swift home the other searchers were returning from their excursions one by one—first Mr. Swift, then Chow, followed by Tom and Bud with their unsettling tale. They were greeted by Craig Benson, who was restless for action.

“Did anyone hear from Anne and the girls?” asked Mr. Swift.

“I’ve been here all along, and the phone didn’t ring,” Craig replied.

“Guess they took that there ‘radio silence’ idea t’heart, Tom,” was Chow’s suggestion. But Tom and Mr. Swift were worried nonetheless as the minutes crept by. They were about to leave on a search when Bud called out: “Here they are!”

Tom’s sports car pulled to a halt, and Mrs. Swift, Sandy, and Bashalli Prandit, a young and pretty Pakistani who had become a close family friend, rushed inside.

“While you men were lounging around, we were chased!” cried Sandy.

Chased!” exclaimed Damon Swift in alarm.

“Not exactly chased,” Bashalli said. “But followed.”

“Not followed, precisely,” corrected Tom’s mother in calm tones. “But there was something suspicious.”

Chow snorted. “Brand my gopher gizzards! If’n they’d been one more female in that car, it’d turn out they never left in th’ first place!”

“Please, Anne, just tell us what happened,” begged Mr. Swift.

“After we picked up Bashalli, we drove along the lake, all the way to Carlopa Heights,” Tom’s mother began. “We didn’t see anyone who looked like either of those men.”

Added Sandy excitedly, “We did see Jennifer Lee walking along with Billy Houtenloff. He’s much too old for her.”

“Now Sandra, that is simply a prejudice,” interrupted Bashalli. “In Pakistan, we― ”

“But― ”

Anyway,” continued Anne Swift, “we ended up driving around in the Heights for a long time. We theorized that the men might be staying with rich accomplices in one of those big houses. All of a sudden Sandy saw car lights behind us.”

“It was as if they’d been driving along with their lights off, then switched them on,” Sandy explained. “That’s pretty suspicious, wouldn’t you say?”

Tom asked, “Could you make out the car?”

“Alas, not well,” replied Bashalli. “As you know, they do not have anything so mundane as street lamps in that rich part of Shopton. They prefer the illusion of a countrified atmosphere, though not so much that they would move one mile away and actually live in the country.

“It was mostly a silhouette, but it seemed somewhat high, like a truck,” Tom’s mother said. “We made a number of turns, going in a big circle and zig-zagging, but they kept following us one block behind. We were getting nervous.”

“Finally Sandra had a wonderful idea,” said Bashalli.

Sandy gave Tom and Bud an imperious look. “I do have them now and then!”

“She had mother Swift turn a corner very fast, and then pull right up in a driveway and choke off the lights. We waited― ”

“Our hearts were pounding!” Sandy elaborated.

“And in moments what was surely the same truck, our mysterious pursuer, rounded the corner. When he saw that he couldn’t see us—if you see what I mean—he gave guns to his motor and shrieked his tires.”

“He went by very fast, and we heard him screech around the far corner of the block. And that was the last we saw of him—or them,” concluded Mrs. Swift. “But we took the long way back just in case.”

“I’m amazed they were so bold as to try to follow you three on a public street,” declared Mr. Swift.

“Wait’ll you hear what happened to us!” Bud exclaimed. “We just got the blood wiped away!”

Blood!” gasped Tom’s mother.

Before Tom and Bud could repeat their stories for the newcomers, Chow spoke up. “Listen, mebbe what I saw had somethin’ t’do with that car that follered the women!”

“You saw something too?” asked Craig as the others turned to the Texan in surprise.

“Sure did!” Chow declared excitedly. “Y’know, you had me nosin’ around Swift Construction in my pickup, but I didn’t see hide nor hair, so I headed off toward th’ lake. Purty soon, blame if I wasn’t goin’ up an’ down the streets of some ritzy part o’ town—prob’ly the same place you women went to—great big houses and no street lights.

“Didn’t seem t’be a soul out on the streets. But then I saw tail-lights a ways up ahead. They’d sorta go faster and slower, n’then almost stop. Thought it was a mite peculiar, so I took a side street and came out behind ’em. Didn’t want ’em to see me, so I kept a ways behind—but I kept up with ’em, even when they started drivin’ all around like they wanted to lose me!”

Tom nodded. “But they couldn’t lose an old Texas bloodhound like Chow Winkler.”

“Not a bit of it!” said Chow proudly. “Wish I coulda kept my lights off, but they started a-goin’ faster, and I figgered it wasn’t safe—besides which, th’ p’lice might have stopped me. Anyhoo, that dang prairie dog tried to shake me, but I kept on his tail.”

“Tom—Daddy—it must have been the same car!” cried Sandy in growing excitement. “Chow must have started trailing him right after he passed us!”

Mrs. Swift gave the cook a serious look. “Charles, did you trail the car all the way to a house?”

“I’m a-feared not, ma’am,” said Chow with evident regret. “All of a sudden they took a corner at top speed, and by the time I got there and turned after ’em, they’d got themselves hid away someplace. But betcha it’s one of the houses on that there street—Penstellar Lane.”

“Penstellar Lane!” Sandy gasped. “That proves it was the same car! I noticed the street sign—it was Penstellar Drive where we—where we― ”

“—where we turned to escape the car that was following us,” finished Bashalli sourly. “Sandy, my dear― ”

“Oh, Bashi, don’t say it,” whined Sandy, turning red.

“Charles, you did a very good job,” pronounced Mrs. Swift. “You couldn’t know that the car you were following was― ”

Us!” moaned Tom’s sister.

When the ensuing gibes and commentary had died down, Tom and Bud narrated their dangerous experience at the cabin.

“Do you really think they were trying to kill you?” asked Craig.

“Whether they were trying to or not, they almost did,” was Tom’s retort.

Added Bud: “We’d be just as stiff either way!”

“I’ll feel much better when Agent Brenner is on the case,” said Mr. Swift firmly.

Craig Benson appeared deeply troubled. “I’ve brought all this down on you folks,” he murmured. “I never dreamed it would turn so serious and endanger you this way.”

After more excited discussion and a call to Harlan Ames—who reported that he had left a message for Hal Brenner but had not heard back thus far—the groups of searchers drifted off on their separate ways. Tom was left alone in the living room for several minutes, where he sat contemplating the day’s events and considering whether his plans for the expedition to Borukundi needed to be altered. A soft sound broke his concentration.

“Bud! Thought you went home.”

The dark-haired pilot shook his head and held a finger to his lips. “Look at this, Tom.” He approached his friend, holding out his left hand. Something dark was smeared on one of his fingers.

Tom frowned. “What is it?”

“Sure looks to me like mud and grass and pine needles,” he replied softly.

“Okay. Where did it come from?”

Bud hesitated. “From the bottom of Craig’s shoes,” he finally said in a grim voice.

“Sure, but why did you― ” Then Tom broke off his comment and regarded Bud with wide eyes. “You’re thinking Craig was the third person in the woods?”

Bud gulped. “Sorry, Tom, but listen. When we got back I noticed a little dirt on the carpet in the living room. Your Mom is pretty careful about that—it seemed unusual. Then I just happened to notice that Craig had changed his shoes, sometime while we were all out searching. It got me to thinking about how he sort of appeared out of nowhere with that wild story. And now he’s got himself living in your house with you.”

“But that was our idea!” protested Tom.

Bud ignored the interruption. “Just now, when Craig went into the kitchen with your folks, I went by the guest bedroom and saw his other shoes on the floor. Tom, stuff like this was all over them.”

“It was all over our shoes, too. That’s why we had to scrape them off on the porch.”

“That’s the point, genius boy,” Bud pronounced. “We walked through the same soft, damp ground as those three guys who left the footprints. I don’t like it any more than you do, chum, but you just might have the enemy living under your own roof!”








          OFF TRACK





BUD’S conclusions amazed Tom. For a moment he didn’t know what to say. A million thoughts flooded his agile brain.

“Bud, sometimes we have to trust our instincts more than the evidence,” he said at last, laying a hand on his pal’s arm. “You don’t really know Craig as I do. He taught me to fly!”

Bud nodded, his face showing sympathy and understanding.

Tom continued, “In mystery stories people just go from clue to clue and jump at conclusions right and left. But in real life you have to be careful—real people can get hurt, and evidence can have an innocent explanation.” Tom had in mind a recent situation involving Bud himself, which he had never fully described to his friend; nor had Tom ever completely forgiven himself for his unfounded suspicions.

“Okay, Tom,” said Bud. “I won’t make a big deal about it. Maybe I’m off track on this. I just wanted you to know.”

Tom thanked him for his loyal concern. Bud went home, leaving Tom sitting alone with his thoughts—thoughts that he very much did not want to have.

The following day Tom and his father met in their shared office and determined that planning would be resumed for the Africa expedition despite the latest indications of danger.

“We can’t risk losing a single second,” Tom pointed out. “Now that they’ve shown their hand, Hoplin and Cameron are sure to try something else to keep us from heading for Africa. We must get underway before they can create more mischief.”

Damon Swift agreed. “We’ve all faced danger before, and the scientific prize of discovering stable antiproton matter in nature is too great to abandon.”

Later in the morning Tom and the other members of the expedition, including Sterling, Hanson, and two other crew members hired for their scientific expertise, reported to the medical department for special inoculations. When it came time for Chow to be jabbed, he yelled:

“Ow! Brand my cow pony’s sore hoofs, where in tarnation did you rake up a crowbar fer a needle, Doc?”

“Well, I’ll tell you, Chow,” replied Dr. Simpson with a wink at Tom and Bud, “I keep this for Texans with specially tough hides.”

The boys roared with laughter and Chow finally grinned as a patch was put over the prick in his skin. He left the room immediately, however, to attend to supplies for the galley of the Sky Queen. “Gotta earn my pay some way, folks,” he said on the way out. “Cain’t get by on jest bein’ colorful!”

Tom turned to Bud. “I want to give the terrasphere tank section a final road test in a more challenging environment than the grounds here at the plant,” the young inventor said. “But I need to be outside the tank to make observations. How about you taking over?”

“Okay, pal. I’ll put those three-ring wheels of yours through their paces.” Bud had just completed two hours of training on the operation of the tank section and crane controls.

Bud went down to the hangar where Terry was housed. The crane and sphere had been detached. The entire machine sported a new coat of paint.

“Is olive green this season’s hot new color?” joked Bud.

“Protective anti-radiation coating,” Tom explained. “Can’t hurt.”

Bud climbed up into the driver’s dome atop the crane turret and took the vehicle outside the Enterprises gates, into the rocky, brush-covered lot that separated the plant from the paved highway by nearly one mile.

For fifteen minutes Bud exercised the motor—a revolutionary steam-pressure turbine powered by a bank of Tom’s lightweight solar batteries—at various speeds. He tested the strange, circular treads, nested inside one another on independent hubs, at various angles of orientation, and ran them backward, forward, and corner-turning as Tom looked on attentively. The three-sided tank platform seemed able to surmount any obstacle with ease. Bud beamed in satisfaction.

Tom sure knows how to put machinery together to get maximum performance, Bud said to himself. Wish he’d get around to designing a con-vertible for me! He picked up the microphone to the external radio and told his friend, “I’ll run down to the edge of the pond, then put Terry away.”

The futuristic tank zoomed along over the rough terrain at fifty miles an hour. Bud, instead of braking it, decided to let the vehicle coast on low idle the last ten feet. A few feet from the pond it was on the verge of stopping, when, without warning, the terrasphere tank picked up speed and raced forward. Quickly Bud jammed on the brake but he was too late.

As Tom gave a shout of alarm, the tank lurched into the pond, sliding down to its soft, muddy bottom until only the crane turret and control dome were left above water.

Bud shoved back the dome access hatch and leaned out as Tom came racing up, breathlessly.

“Bud! Are you― ”

“Oh, don’t ask!” Bud yelled back, shamefaced. “I guess I can’t blame this on sabotage.”

Tom called out a crew from the plant, who arrived in minutes with a winch to pull the tank from the muddy water. “Golly, I’m sorry, Tom,” Bud said to his friend. “I can’t understand what went wrong. She accelerated by herself and wouldn’t brake.” Despair entered his voice. “Oh man—Terry’s probably ruined and our trip will be delayed.”

Tom threw an arm around Bud’s shoulder. Smiling, he said, “Are you kidding? This is exactly why I had you test her out—to find these flaws in Terry’s design. I can already guess the weak point in the mechanism. I’ll have her fixed up in no time.”

“Nevertheless, when we’re tearin’ around in the jungle, I think I’ll leave the driving to you,” Bud retorted.

It was late in the afternoon when Tom, Bud, and Craig—newly cleared by Doc Simpson—gathered in Tom’s office to talk over plans for leaving.

“How soon will it be?” Craig asked.

“In a couple of days,” Tom replied. “We have to wait for proper clearances for Sterling, Hanson, and Mandy and Ry.”

“Who are they?” Craig inquired. “Mandy and Ry?”

“The rest of our crew,” Tom answered. “Mandelia Akwabo was born in Kenya and is a specialist in the geography of Central Africa. She also speaks the local dialects fluently. And Ryerson Cully is one of this country’s top geophysicists.”

“Specializes in mountains that blow their tops,” Bud commented.

Tom’s office phone buzzed. He picked up the receiver and after a moment said, “Bring it in, please, Trent.”

The secretary opened the door and handed him a faxed cablegram. As Tom quickly scanned the message, his face turned pale.

Bud noticed his friend’s worried expression. “What is it?” he asked.

“This cable,” murmured Tom, “is from the authorities of the principal nation claiming ownership of the Borukundi region.”

“Bad news?” Craig asked quickly.

Tom gave a sigh of puzzled despair. “We’re being refused the right to enter Borukundi!”

Tom and his companions were stunned by the message in the cablegram. The planning, the effort, the time—all seemed hopelessly lost.

“Why didn’t those people in Africa tell us this before?” growled Bud. “It can’t be!”

But Craig Benson shook his head. “I’m afraid it’s all too predictable. Three countries border Borukundi. One is recognized by the United States and most international organizations as having a legitimate historical claim to the area. But Europe recognizes another, and most of Africa prefers the third. So they compete in undercutting one another and react with paranoia when anyone wants to go in officially.” He added that most scientific expeditions into Borukundi now went without having acquired the legal right to do so. “That way the various governments can disclaim all knowledge, and denounce any findings that contradict their propaganda machines.”

“It’s crazy!” cried Bud.

Tom continued to stare at the cablegram. Presently he said, “I’m beginning to wonder if perhaps there isn’t something fishy about this deal. It seems to me that such a message would have been sent to our government first and relayed to me.”

“That makes sense,” said Craig. “On the other hand, the nation in question has been known to do things in odd, erratic ways.”

Frowning, Bud pointedly ignored Craig’s comment. “Then you mean,” Bud put in, speaking to Tom, “that maybe Hoplin or Cameron or the mystery third person are in cahoots with some official over there and sold him the idea of sending this cable?”

“Could be,” Tom replied. “In any case, I want to talk to Dad about this before I make another move.”

The upshot of the conference between father and son was that Mr. Swift agreed the cable should be investigated and set the wheels in motion to do this. Hours later he summoned his son to their private office.

“Tom,” he said, “you can proceed with your trip as planned. That cablegram was a fraud. The officials know of no order, such as you received, being issued by their government.”

“What a relief!” said Tom, grinning with anticipation of carrying out his plans for the African expedition.

“In fact,” Mr. Swift continued, “that government, at least, says they’re eager to have you come. However, they sent a warning about General Boondah and his followers causing trouble in the area where the Maba tribe is.” After a moment he added:

“I have the impression that they don’t mind allowing you to put yourself in harm’s way, as you may be able to give them information they can use—if you manage to make it back.”

Tom smiled. “With luck and a little diplomacy, our group ought to be able to make friends with the natives.”

“You’re right in that regard,” said Tom’s father, “but don’t underestimate the ‘luck’ element. Sometimes it’s difficult to win the friendship of people in the world’s traditional cultures. They instinctively distrust strangers, and often connect them to colonialists and exploiters. Be certain to use every precaution. Supply yourself and your crew with adequate protection against possible attacks.”

“I will,” Tom promised.

He immediately sent word to the other members of the expedition. There was a sigh of relief from all of them and a whoop of excitement from Bud. “I’ve got jungle jitters already,” he joked.

With this unexpected obstacle cleared away, last-minute preparations went forward at a feverish pace and finally the day arrived when the explorers were ready to depart.

“We leave at five tomorrow morning,” Tom announced to his friends.

That evening, at The Glass Cat coffee house where Bashalli Prandit worked, Sandy and Bashalli gave a surprise farewell party for Tom, Bud, and the other expeditioners—though in truth it was hardly a surprise.

“This is a most arresting custom,” Bashalli commented to Tom with a teasing smile. “You seem to have one of these going-away parties every few weeks. You have had so many going-away parties I’m surprised you haven’t gone away for good!”

“It’s a living, Bash,” Tom joked. “Join Swift Enterprises and see the world.”

“Or outer space, or the bottom of the sea. Do you not ever feel the desire to settle down, Tom Swift?”

“Not at the moment,” replied the young inventor carefully. “I’m only eighteen, you know.”

Bashalli rolled her eyes.

“Yes, and as time is counted by the Swifts, no doubt you will be eighteen for many more years to come. I trust that some day, Tom, the hands of the clock will turn even for you.”

Tom gave a wink and said, “When that happens, Bash, I’ll make sure to let you know.”

Twenty young people were there and the main room of the coffee house was alive with excited chatter.

“That’s quite a place you’re going to,” said a youth named Will Brown. “I hear one of the tribal kings weighs two hundred and fifty pounds and has as many wives!”

“Stay away from him, Tom,” ordered blond Jane Denton. “He may try to give you one of them!”

“There’s an old chief in that country who has nothing the matter with him,” said Will, “but he’s too sacred to touch the dirty old ground, so he’s carried everywhere he goes—from bed to bath to table.”

“Wow! What a life!” Bud exclaimed. “I think I’ll hunt up the guy and offer to pinch-hit for a while.”

At the height of the gaiety supper was announced by Sandy and the guests began to file past the tables where refreshments, set out buffet style, were awaiting them. As the young people heaped their plates with food, Bud remarked to Tom with a grin:

“This is swell! We ought to go to Africa every day!”

Suddenly there was a shriek from one of the girls, and the sound of a plate dropping from someone’s startled grasp.

“Tom!” Sandy cried. “Who—what—is it?”














TOM WHIRLED and his expression turned to one of complete astonishment. Then he broke out laughing. Pointing to the swinging doorway to the kitchen, he jokingly exclaimed, “Ugh! Who let that in?”

Standing there was a grotesque figure. Upon second glance everyone recognized him as Chow, who had been asked by Bashalli and her brother Moshan to help with refreshments. Now he was attired in what appeared to be his idea of what a well-dressed African native would wear. He had daubed his forehead with streaks of red make-up. The headdress he wore was adorned with long feathers that drooped in his face like banana peelings. A short, red, sarong-type garment reached almost to his knees. His pudgy bow-legs looked like two pale and battered lawn-sprinkler pipes.

Though howls of laughter issued from the young people, Chow stood tall with a noble and dignified demeanor. He had not meant his entrance to be at all humorous. Muffled grumbling could be heard from behind the cluster of feathers.

Quickly seeking to spare his feelings, Tom rushed up and gave his rotund friend a hug, then led the room in a round of warm applause.

“I congratulate you, Chow Winkler,” said Mandy Akwabo, who was radiant in her traditional African daishiki. “Your costume is perfectly authentic for the Maba culture, including the red scar-marks.”

“I’m glad of that,” said Tom. “We don’t want to seem to be making fun of African traditions.”

Mandy laughed. “And what is wrong with making fun? Many traditions have earned the right to be made fun of—African, and perhaps some of yours as well.” Her eyes twinkled in ironic good humor.

Commented Bashalli, “Now this is someone I could get to like!”

Though Chow appreciated the applause, he was obviously somewhat embarrassed. “It was her idea, Tom,” he whispered, nodding in Mandy’s direction. “Made me do it, if’n I wanted to get any of her authentic recipes.”

“I see,” said Tom. “Er—did you say recipes?”

As the Texan turned grandly and retired to the kitchen, Bud sidled up and remarked, “Tom, if we start running now, we could reach the street before he comes back.” Tom smiled wanly.

Chow returned in a few minutes with a huge tray, on which was a steaming mass of green plants.

“What’s that?” Tom asked. He added quickly, “Looks delicious!”

“I bought these here at one o’ them tropical fish an’ plant places,” the cook replied. “An’ brand my burnin’ sagebrush, it’s good!” The expression on his face showed that anyone who dared disagree would get an argument in reply!

To avoid hurting Chow’s feelings again, everyone took a portion of his tropical concoction. Bud was first to put his fork in the greens and swallow a small mouthful. From his pained expression one would have thought that he had swallowed the fork instead!

“Are you sure it wasn’t the wrappings you cooked,” Bud blurted out, “instead of what came in them?—mm, just kiddin’ ya, cowboy!”

Tom took a deep breath, closed his eyes, and placed some of the unusual food in his mouth. “It tastes like decayed spinach with horse-radish sauce,” he murmured to Bud.

“How do you like it?” Chow asked, grinning broadly. Then, without waiting for an answer, he added, “Miss Akwa-bobo over there says it’s a big favorite where she comes from—bigger’n pizza with th’ teenagers.”

“I provided our chef here with many such recipes,” Mandy said proudly.

Tom made no response to this comment, deciding to deal with the threat when the time came!

The party broke up at midnight in order to give the expeditioners some chance at a night’s sleep. But they all were on hand at the Enterprises’ airstrip for the early-morning take-off, along with the families of Tom and Hank Sterling, and Bashalli.

“Please do be careful, Tom,” Bashalli begged as the giant Flying Lab rose on its elevator from its underground hangar. Her bravado was gone for the moment.

Tom put his arm around her shoulder. “I’ll be back soon,” he assured her. “And not a day older!”

“No, and not glowing in the dark either, I should hope.”

Sandy and Bud, meanwhile, exchanged farewells. Tom kissed his mother and Sandy, and gave his father a firm handshake. Then he climbed into the mammoth plane and went to the pilot’s seat. Bud, as copilot, sat next to him, and Craig just behind.

Checkoffs were made with military precision and soon the giant plane was ready to take off. Tom had been pleased that eleventh-hour clearances had made it possible for Doc Simpson to accompany the expedition. Besides acting as ship’s doctor, the youthful physician also wanted to do some research on cures accomplished by African village shamans—“medicine men,” as they were sometimes called.

As Tom checked his instruments, his thoughts turned to Hoplin and Cameron. There had been no sign of them since the night of the chase in the woods, and Hal Brenner had found no further trace of them in Shopton. It seemed they had been secretly making use of the vacation cabin without permission from the owner, who lived many miles away in Albany. Where were they now? If they had been somehow responsible for the cable which had failed to keep Tom home, were they preparing a trap in Africa?

Putting these thoughts aside, Tom touched a switch and the smooth, thundering drone of the jet lifters responded. Amid waves of farewell from the members of the expedition and the group on the runway, the giant craft rose straight into the air like a freed carnival balloon, slowly at first, then rapidly picking up speed.

Altitude attained, Tom applied forward thrust and pulled back on the yoke. The Sky Queen shot ahead and zoomed off into the blue.

“This is a remarkable ship!” Craig said, still marveling at the facile operation of Tom’s Flying Lab as Chow brought in breakfast.

Soon the East Coast was left far behind, with the green water changing to blue. The craft hummed along at twelve hundred miles an hour while the boys enjoyed their ham and eggs.

“Tell us something about the language of tropical Africa,” Bud asked Mandy. “Is it hard to learn?”

The geographer smiled. “It’s hard to believe but there are thirty-eight basic native languages in this general area,” she said. “There are many common words and expressions, but also many distinctive dialects. The principal Maba dialect—there are three, you know—is related to Bantu.”

“Say there,” asked Chow, “is this one o’ them there languages where you hafta make all those noises, like clicks and whistles and such?”

“Fortunately no,” laughed Mandy. “That is further to the south. Basic Maba is not hard to learn, if you have a good ear.”

Craig commented, “I picked it up pretty easily. It helped that some of the tribe spoke French, which I also know.”

“Me too,” said Doc Simpson. “I can get along in any country that speaks third-year French!”

Tom had been listening to the conversation with a smile as he monitored the instruments. Then suddenly he frowned and leapt forward in his seat.

“What’s wrong?” Craig asked.

“We’re losing power on all engines!” Tom said, and worked the throttles frantically.

Approaching the copilot instrument panel, Bud noticed that the fuel-pump RPM indicator showed an alarming decrease.

Tom commanded, “Cut in the fuel-pump boosters, Bud!”

His friend threw the switch. No change!

Tom scanned the instruments again. “Altitude’s going—fast!” he declared. “If we don’t get power back in a couple of minutes, we’ll have to ditch!”

“Y-you mean in the ocean?” cried Ry Cully fearfully. The slender, gray-haired geophysicist was the eldest member of the crew. Despite his enthusiasm for the overall project, he had confessed a manageable fear of flying.

Hank Sterling made some suggestions as to what might be going wrong. Tom tried various adjustments to the controls, but nothing worked.

“The aeolivanes are still operating, thank goodness,” Tom muttered. “But without jet lifters or the forward jets, we’re just a great big glider. We won’t be able to stay aloft.”

“And—we don’t have either of those little planes on the hangar deck, either,” said Craig.

“We’ll have to ride her down for a water landing,” Bud said.

Arvid Hanson had entered the control cabin behind them. He quickly grasped the situation. “Tom, should you radio our position—while the radio still works?”

Tom stared at him grimly. The Flying Lab was beginning to shudder—a sign of insufficient airspeed.

Frantically, the young inventor scrutinized his instruments for some sign of the cause of the mechanical failure. Nothing new showed up. The Sky Queen continued to sink seaward like a wounded gull.

“We’re down to fifteen thousand feet!” Bud called out, trying to keep his voice steady. “Tom?”

Tom did not reply. He worked the throttles again, but the rate of forward thrust was decreasing more and more rapidly. Suddenly Bud, glancing out the forward viewpane, cried out:

“Tom, look up there! It looks as if we’ve picked up ice in our engine air inlets!”

The pilot peered at the gaping orifices above and ahead of the control cabin, clustered beneath the craft’s snub-nosed prow. “You’re right!” Tom exclaimed. “Ice is choking off the air to our engines! The pumps slow automatically without a sufficient airflow.” The Queen’s futuristic engines made use of a special hydrogen-based fuel which required a constant influx of atmospheric oxygen to maintain combustion.

“Ice!” Craig repeated in surprise. “The sky is clear! Where did all that moisture come from?”

Tom clapped a hand to his forehead. “I must have been daydreaming!” he said. “A little while ago I pulled the Sky Queen up through a layer of cirro-stratus clouds. But the thought of moisture freezing on the inlets never entered my mind!”

“I’ll switch on the inlet de-icers!” Bud offered. He dashed to the flight engineer’s control panel, situated just to the rear of Craig’s seat, and threw a series of switches. Nothing happened!

“Jetz! The ice is so thick,” Bud yelled, “it won’t break off!”

“We’re down to ten thousand feet!” declared Craig, as he caught a glimpse of the altimeter.

Setting his jaw, Tom cut off the sputtering jet lifters completely and shoved the control wheel forward. The Sky Queen pitched into a steep dive. His companions stared out the front viewpane as the deck tilted sharply and they approached the ocean at an alarming rate.

“Good gravy!” Ry Cully gasped. “Are you planning to drown us?”

“Tom knows what he’s doing!” retorted Bud.

Tom held the craft in its diving position. Then, when a crash seemed inevitable, he hauled back carefully on the control wheel, pulling the nose of the plane up. The fast recovery from the dive caused the occupants to feel as if they weighed tons. A veil of gray gauze seemed to drop over their eyes.

Can’t black out now! Tom told himself. A slight forward motion on the wheel decreased the angle of ascent and relieved the threat of unconsciousness.

Craig, gripping his seat, was amazed to discover that they were flying only a few feet above the surface of the ocean! Bud and Craig, though they had guessed the reason for Tom’s maneuver, were uneasy.

A slight shudder passed through the skyship. “Our tail is dipping into the water,” said Hank Sterling quietly. The waves hurtled past beneath the viewpane at bullet speed; it was impossible to watch without becoming dizzy. Tom eased the Flying Lab down, down—until a plume of spray shot up against the plexi-quartz window. The very front of the bottom deck had clipped a swell!

That was the signal Tom had been waiting for. He fed full power to the pumps and gunned the lifters and the forward jets simultaneously. This time they responded! The Queen catapulted skyward with dizzying power, and in less than a minute they had regained the stratosphere.

The intercom crackled to life. “Brand my—my bouncin’ belly! What th’ Sam Hill’s goin’ on?”

The tension broken, laughter rippled through the command deck. Over the ship’s speakers, Tom explained to Chow that he had just dealt with what he termed a transitory technical problem. “The pilot and crew regret any inconvenience,” Tom joked.

“You made me proud to have been your teacher, Sci-Fi,” said Craig.

“I’m glad it’s over,” responded Tom, wiping perspiration from his forehead.

“But what did you do, actually?” asked Ry breathlessly, nervously cleaning his eyeglasses.

Tom explained his unusual action to the passengers. “Hope I didn’t scare you out of ten years’ growth,” he added. “But I was pretty sure we’d be able to shake off the ice that way. At this time of year,” he explained, “water is comparatively warmer than the air over it. Therefore, by conduction, air within about fifty feet of the water is heated. I figured it would help the de-icers flake off the ice. The shock of bouncing on the water helped, too.”

The rest of the trip above the clouds progressed smoothly. Soon the Flying Lab was streaking over the green jungles and sparkling rivers of equatorial Africa. Six hours after take-off—it was now five o’clock in the afternoon, local time—Tom started downward. With their immediate destination, the city of Kinshasa, only minutes away, the occupants of the Sky Queen became excited.

“I see the city up ahead!” Bud exclaimed.

“That is Brazzaville,” said Mandy. “Kinshasa lies a bit further east, just over the Zaire border. Both are very populous cities.”

Reaching Kinshasa airspace at last, everyone gazed in surprise at the sprawling city below them. The modern-looking capital of the former Belgian Congo, called Leopoldville in colonial days, jutted out of the green jungle like a point of light in a dark sky.

Tom banked his huge craft and headed east of the city toward the modern airport. Receiving clearance from the control tower, he guided the Flying Lab down to a skillful landing.

“Good thing you corrected that heat problem with the lifters,” Bud commented to his friend. “Otherwise you’d have to carry your own landing pad with you!”

Several small automobiles came out to greet the Americans. After officials of the local government had welcomed the well-known youthful inventor and his group, they invited them to go into town. All accepted but Hank and Arv, who volunteered to stay aboard the Sky Queen and keep an eye on things—including the terrasphere equipment.

During the drive to the center of Kinshasa, the explorers admired the attractive city. Fine houses and schools had been built along the outlying streets, and the center of the city was filled with modern buildings that speared skyward. The vehicles soon reached the Boulevard Albert Ier. Luxurious, modern cars rolled along the wide ribbon of road that cut through the African metropolis. Well-dressed men and women strolled the streets.

“It’s funny,” Chow remarked to Mandy, “but I figgered this lil’ ole Congo country was jest a lot o’ mud huts an’ people wearin’ only a few duds—no offense, ma’am.”

“Who could be offended by such charming naiveté?” responded the geographer. “But I am much afraid not all parts of this city are bright and modern. It is the same in my native Kenya. But there is progress, however slow in coming.”

“Africa is changing, all right.” Craig smiled. “But it still has its wild regions, Chow. Only a fifteen-minute ride from the center of this city will still take you into a dense jungle.”

When the travelers arrived at their hotel, courteous porters showed Tom and his companions to neat, modern rooms. The escorting officials made certain everything was satisfactory, then left.

Ten minutes later there was a knock on the door of the room Tom was sharing with Bud. “Come in!” he called.

A tall, elegant man in a white uniform entered.

“Mr. Tom Swift?” he inquired.

“That’s correct,” responded Tom, and then introduced Bud.

“My name is Frederick Shopfer Nkata,” the caller announced with great dignity and a slight accent. “I am from the local police headquarters.”

“How do you do, sir,” Tom answered.

“I received a cablegram from one of your security men,” the officer stated. “A Mr. Ames, I believe.”

“Oh, yes.” The young inventor smiled. “I told Harlan that I wanted to make contact with the local authorities.”

“My facilities are at your disposal,” declared the caller.

“Thank you,” replied Tom. “I must say you were very prompt.”

“Indeed so. It is my practice to be prompt. But alas, I am not here because of Mr. Ames. I must inform you of a rather embarrassing matter, of a somewhat delicate nature. Please understand, I am only carrying out my sworn duty.”

Bud glanced at Tom in alarm, then at Nkata. “What’s up? A problem?”

“Rather a large one, yes,” the man replied. “I do apologize, but I must ask you two to accompany me to police headquarters.”

Tom gaped at the officer in bewilderment. “Can you tell us what is the matter, sir?”

“Yes, of course. I am afraid we have reason to believe that your party is engaged in smuggling.”

Tom was aghast. “Smuggling? Smuggling what?”

“Elephant ivory—a serious crime.”









          SIX HOURS LOST





“YOU’RE TALKING to Tom Swift!” Bud exploded. “The accusation is just― ”

Tom placed a hand on his pal’s arm and said to Nkata, “We’ll accompany you as you wish. But can you tell us anything about this charge?” He told the officer of his suspicions concerning Hoplin and Cameron, and produced the sketches Craig had drawn. “One of our party, Mr. Benson, was previously a victim of spurious accusations, probably by one of these men or their accomplices.”

“My men will be alert to any sign of them,” the officer stated. “We do not wish any undesirable characters in this country.” He stood pondering a few moments, then said, “I do not know if there is any significance to this, but an unidentified plane was spotted flying high over a nearby town this morning. It was thought to be of American manufacture and heading northwest across the jungle, in which direction lies the disputed province of Borukundi.” After hesitating, he continued, “Though it is somewhat irregular, I will tell you that the source of the accusation is anonymous. It was transmitted by a third party to the editor of our newspaper, who regarded its provenance as credible.”

“Well, you can ask anyone in the U.S.A.—they don’t come any more honest than Tom Swift and his father!” Bud declared hotly.

“You are no doubt quite right,” said Nkata stiffly. “Still, it is for my superiors to determine. Let us go.”

Tom and Bud were driven to a large building, central police headquarters, where Tom was asked many questions about the purpose of his expedition, which he answered forthrightly.

“I am satisfied,” pronounced their questioner at last, who identified himself as Deputy Chief of Police Ikabo. “In my opinion, the secret accusation was intended only to raise suspicion and detain your party.”

“Then I assume we are free to continue on to Borukundi,” Tom said.

“There is one more step to be taken,” Ikabo responded. “I am responsible to my government, you see, and I must demonstrate the thoroughness of my investigation. Have you any objection to our officials inspecting your aircraft?”

“No,” replied Tom, “provided that I or one of my employees is allowed to accompany whomever does the inspecting. You see, the Sky Queen is full of delicate scientific instruments, and― ”

“I do understand,” said Ikabo with a crisp nod. “Will eight o’clock be convenient?”

Tom checked his watch. “But, sir, it’s after eight now.”

“I mean eight tomorrow morning, of course.”

Tom groaned inwardly. He had hoped to have departed by that time. But he had no choice but to agree.

The morning inspection of the Flying Lab began on time, but stretched on and on. Crates and lockers were opened, their contents sifted through with great care. Even the terrasphere descent cabin was poked through. It was nearly two in the afternoon when Ikabo pronounced himself satisfied and signed the papers allowing the Flying Lab to go on its way.

“Six hours lost!” Tom muttered to Bud in disgust.

“Whoever gave the police that phony tip got just what he wanted,” Bud replied; and Tom knew the young pilot had Craig Benson in mind.

Soon the midday bustle of Kinshasa was broken by the roar of the Sky Queen’s powerful jets as Tom took off for the final stage of their journey—the mysterious mountain near the Maba village. Below them the gleaming green forest, much of it containing rubber-producing trees, was occasionally broken by grassy plains. These immense veldts served as grazing lands for buffalo and antelope.

“To this day, some of this jungle is almost inaccessible by surface travel,” Craig pointed out. “It can still take days to go a short distance.” He kept watching the terrain keenly and finally said excitedly. “Quick, Tom! Bank sharp to starboard!”

The young inventor maneuvered the craft into a turn. Craig searched the ground below.

“That’s where I crashed!” he declared suddenly. “And look over there! It’s misty, but you can make out the lines of that magic mountain we’re headed for.”

Tom and Bud gazed in awe at the wilderness of tangled trees. “Craig,” said Tom, “you sure were lucky to come out of this place alive!”

“I know it,” the cargo pilot agreed, then said, “The Maba village is approximately three miles northeast of here.”

The Sky Queen covered the distance in a matter of seconds and Craig pointed to a cluster of small buildings almost hidden by towering trees.

“That’s the village! They call it Ogaphabu.”

Chow turned to Mandy Akwabo. “I kin almost pernounce that,” he commented proudly. “What’s it mean, ma’am?”

“Why, it means ‘the place where we live’,” she replied with a smile. “A very good name, don’t you think?”

“Reckon so,” said the cook doubtfully. “But I don’t think it’d get too far back in Texas!”

Village men, women, and children rushed outside and stared upward at the silver behemoth floating high above them among the clouds.

“We’ll set down in that clearing to the west of the village,” Tom announced. “Looks like it’s a rock outcropping and free of vegetation.”

He circled, then brought the Flying Lab down to the chosen landing spot. The huge ship settled with a roar.

The members of the expedition stepped out of the plane and gazed at their surroundings. How still and sweet-smelling the jungle was! But how hot! Fascinated, the party stood for a minute taking in the strange exotic beauty around them. Vines, bearing orchids of every hue and shape, trailed from the trees. Masses of tremendous ferns, with leaves twelve feet long, bordered the tropical forest.

Craig pointed to the birds of numerous breeds and varicolored plumage. Startled by the Sky Queen’s descent, they were crying shrilly as they flitted among the trees. Many of these, he said, belonged to the parrot family.

“And those flowers are a source of some of the herbal medicines used in this part of Africa,” noted Dr. Simpson. “They won’t grow in North America. I’m anxious to study them.”

He had barely spoken when about twenty native men emerged from the trees. They all wore bluejeans or pants of khaki sailcloth but were mostly bare-chested, except for one older man who was evidently their leader, who wore a colorful, poncho-like garment. Every man carried a formidable-looking spear. The men to one side of the leader carried their spears in their left hands, the ones on the other in the right.

“Don’t let those spears worry you,” advised Craig. “It’s just part of their ritual ceremony in greeting important visitors.”

“A great relief!” piped Ry Cully.

The natives stopped before Tom’s party, and the leader began to speak slowly in the language of the Maba.

“He says he greets you as brother-friends, and extends his hospitality,” Craig said. “He asks why you have come, and what are your intentions?”

Chow edged forward next to Tom and said softly, “Tell him we’re relatives o’ the sky-gods, an’ we’ve come to visit in our shining canoe to see the sights.”

Meanwhile the leader had resumed speaking, and Craig translated again. “He asks if there are any television cameras on your jet, as he wishes to document the abuses they have suffered from the guerrillas.” He glanced reprovingly at Chow, who reddened and backed away.

“Please thank him, and tell him that we are here for scientific purposes and will not interfere with their village,” Tom said to Craig.

“That’s a little advanced for me,” said Craig.

“I will translate,” Mandy offered.

A moment after Mandy had concluded, the Swift team was amazed to see the villagers drop to one knee and bow their heads to the visitors in great humility.

Tom, walking toward the group, said happily, “It looks as if they’re going to be friendly.”

But suddenly the natives, at a signal from their leader, stopped bowing. As one, they arose and hurled their spears at the Americans!

Caught off guard, the visitors flattened themselves to the ground and the first volley of spears miraculously missed them.

“Into the plane!” Tom yelled.

His companions needed no urging. They made a dash for the Sky Queen, but as they reached it, the wildly yelling natives launched a second volley of spears. Some of the weapons crashed against the fuselage of the craft, but the shaft of one struck Hank Sterling a glancing blow on the shoulder. He slumped to the ground. Then Hanson let out a yell of pain and fell, clutching his right leg.

With the others already inside the plane, Bud helped Sterling up the ladder and through the hatch. Tom had run to Hanson, who was wincing with pain but trying to stand up.

“Quick! I’ll help you,” Tom offered. “Lean on me!”

Assisted by the young inventor, Hanson managed to make his way up the boarding ladder and through the belly hatch of the skyship. His face was gray with pain.

“Friendly little greeting ceremony, huh?” Bud said angrily to Craig.

Craig shook his head. “I don’t understand it.”

“Are you certain they were from the Maba village?” asked Mandy.

“Yes,” Craig replied. “The man leading the delegation is their chief, Dothokan.”

“He didn’t seem to recognize you,” objected Bud suspiciously.

“It would be a violation of the ceremony to single me out for a greeting,” explained Craig.

“That’s true,” Mandelia confirmed. “It would be an insult to the visiting chief, Tom Swift.”

Tom helped Arvid Hanson to the infirmary compartment, which was on the upper deck. Hank Sterling was already there, being attended to by Dr. Simpson. Sterling’s shoulder was only bruised, but Hanson’s injury was diagnosed to be more serious.

“The spear point went through to the bone,” said Doc Simpson. “Fortunately it seems not to have severed any muscles, but you’re going to be pretty sore for a while, Arv, and we’ll have to watch for signs of infection.”

“Should we fly him to a hospital?” asked Tom.

Before Simpson could respond, Arv groaned out: “Absolutely not! You’ve lost enough time, Skipper!”

Doc Simpson smiled and said, “I suppose I’ll concur with my learned colleague, ‘Doctor’ Hanson. I should have no difficulty treating him with what we have here on the Queen.”

Meanwhile the group of villagers had been banging futilely on the hull of the Flying Lab with their spears. As Tom arrived in the control cabin to observe what was happening, they stopped at a signal from their chief.

“Now what?” asked Tom.

The old chief seemed to be awaiting something. When Craig Benson entered the cabin and became visible through the downward-slanting viewpane, Chief Dothokan began making gestures.

“He wants me to come out to talk to him,” Craig murmured.

“You’re not going to do it?” demanded Tom. “They may capture you, or worse!”

Craig said slowly. “I am going out. I’m sure Dothokan will not harm me. In sign language he is offering me protection in the name of his tribal gods—I have never known a Maba to violate a sacred oath like that.”

Tom nodded his consent, but said, “We’ll be watching.”

Craig went outside and spent several minutes talking animatedly to Dothokan, who stood some distance away. The spear-carriers withdrew to a further distance, watching impassively. Finally the chief turned away, and the others followed.

Reentering the ship, Craig gave an account of the conversation to Tom and the others.

“The Maba are furious. Dothokan says an aircraft flew over the village last night and dropped incendiary canisters that nearly set Ogaphabu on fire and injured dozens of people. They couldn’t see the plane and at first thought it was the work of General Boondah, whose followers periodically attack them to try to drive them across the border. But when the Sky Queen appeared, they assumed we were behind the incident. They have no modern weaponry here—the guerrillas confiscated them years ago—so they had to use trickery to repel us.”

“Did you explain that we had nothing to do with it?” Ry inquired.

“Yes, and I think Dothokan finally believed me. He said he was greatly ashamed. But he warns us that if we approach the taboo mountain—they call the mountain Goaba—we will not be allowed to enter the village.”

Tom expressed surprise. “These people seem too advanced to believe in old superstitions like that.”

Mandelia Akwabo spoke up. “Tom, it is not so much that they literally believe that our operation will anger the ancient spirits; it’s just that violating their customs is a sign of great disrespect. They cannot ignore it. Their children would not look up to them if they allowed us to ‘dis’ them like that!”

As Tom and the others nodded their understanding, the intercom buzzed. “Tom, you’d better come up to the infirmary right away,” came the worried voice of Doc Simpson. “Arv Hanson has suddenly taken a turn for the worse. I’m afraid he may have been poisoned!














TOM, Bud at his heels, clattered up the metal stairs to the deck above and burst into the infirmary. Arv lay on a small cot which swung down from a bulkhead, and Tom could see at a glance that he was very ill. His skin had turned pale and splotchy, and perspiration rolled off his brow.

“How do you feel, Arv?” Tom asked gently.

“N-not so good,” the big Scandinavian replied. “I’m s-sorry, Tom.” His voice was weak, his breathing labored.

“It came on over a matter of minutes,” explained Simpson. “I believe the spear-head was dipped in something, a poison or drug that I can’t identify. It seems to be affecting his ability to breathe.”

“Now we’ll have to fly him to a hospital,” Bud declared in a low voice.

Arv began to protest but Tom cut him off. “Save your breath, Arv. We lift off immediately.”

Tom and Bud ran back to the control deck. After making an announcement of Arv’s situation and their imminent departure over the ship’s public address speakers, the young inventor revved the jet lifters and began to slowly increase their thrust. The Sky Queen began to rise from the clearing—one foot, two feet…

Suddenly the whole ship seemed to quiver and list over to one side.

“Something’s wrong!” Tom cried, hands darting over the controls in an attempt to compensate. But things only worsened: the lifters began to sputter, and Tom had to set the ship down again.

“Not more ice, I hope!” wheezed Ry Cully.

“No sign of that,” Tom responded distractedly. “But—look at the instrument panel, Bud!”

The needles and indicators of the various instruments were wiggling wildly back and forth!

“Something must be wrong with the electrical system,” suggested Bud. “Maybe the reciprocating capacitors have gotten out of phase.”

“Can’t tell,” was Tom’s brusque comment. He scooped up the microphone from the control board. “We’ll have to have a medevac chopper fly here from the nearest city.” But when Tom attempted radio contact, red warning lights flickered to life on the board and static roared from the loudspeaker. “No go!” proclaimed the blond youth in disgust.

“You surely must have radio equipment with an independent power supply,” protested Mandy.

Tom nodded. “Yes—we do—the radio in Terry!”

“But is that strong enough for real distance?” asked Craig.

“I think we’ll be able to find someone in range,” Tom responded. “They can relay the message for us.”

The group trooped down to the hangar hold, and Tom climbed up into the tank’s control dome. He reappeared a moment later shaking his head in puzzled discouragement.

“The terrasphere’s radiophone is blitzed-out as well,” he said. “So it’s not just a problem with the ship’s electrical system.”

“But what else could it be?” Craig exclaimed.

Now a foghorn voice spoke up from behind them. “I know what it is, folks,” said Chow Winkler. “It’s them mountain spirits! Looks like we got ’em mighty riled up, and they’s workin’ their black magic on us!”

“Charles Winkler!” reproved Mandy. “Tell me you don’t believe in spirits and black magic!”

“Naw, ma’am, I don’t believe in it at all,” Chow replied defensively. “But I hear tell it works even if you don’t believe!”

Tom rubbed a hand through his ragged crewcut, frantic with worry over his friend. “I know what I’m going to do,” he said at last. “If the villagers are familiar with this poison, then they may know of an antidote. I’m going over there on foot to get it.”

“We’ll all go together,” said Mandy; “those of us who can walk, at least.”

Tom shook his head. “No. I don’t want to alarm the villagers, or make them think we’re attacking. Just me, and Craig to translate, since he knows the chief.”

“I’m going too!” Bud declared with a veiled glance at Craig. “And if you don’t approve, Tom—save your breath!”

The three immediately set off through the underbrush in the direction of Ogaphabu, which lay about one mile to the east. The sun was now low on the horizon, and the shadows were reaching out hungrily on all sides.

“Tom, you must have at least a theory about what’s gone wrong with our equipment,” Bud urged.

“I always have plenty of theories,” the young inventor retorted. “It could be some kind of sabotage, of course—perhaps one of those inspectors in Kinshasa planted some kind of device on board, which he activated by remote control. But I’m more inclined to think that our proximity to the taboo mountain is involved—rampaging antiprotons is essentially an electrical phenomenon, you know.”

“The puzzle is, why didn’t we experience the effect earlier, when we first arrived?” wondered Craig Benson. “I mean, the mountain hasn’t moved!”

“Beats me,” said Tom. “And look at this!” He and the others were carrying Swift impulse rifles, which could discharge pulses of electricity to stun or disable antagonists. Tom aimed his rifle at a broad leaf and pulled the trigger-button. Normally the invisible discharge would have produced a char-mark on the leaf. But now, a few weak sparks fell from the barrel, and there was no other effect.

“So even your electric rifles are out of whack!” Craig said in discouragement.

“Which leaves us defenseless,” Bud added grimly. “We’d better get ready to fight with out hands!”

“I’m hoping we won’t have to fight,” said Tom.

Through a gap in the foliage they could now see, far ahead, a few of the outlying buildings of the village. Even as they did so, ominous figures seemed to rise out of the brush and shadows around them.

“Well, genius boy, we’re about to test one of your theories,” Bud commented tensely. “These guys look friendly to you?”

On the Sky Queen the minutes crept by with agonizing slowness. Arv was worse; he had lapsed into a state of semiconscious delirium, breathing with the help of a pressurized oxygen mask as Doc Simpson mopped his brow.

“Has he stabilized?” asked Hank Sterling, his shoulder swathed in bandages.

“No,” Simpson replied in a soft voice. “If we can’t break this thing within the hour, I don’t think he’ll make it.”

Sterling looked him in the eye. “Will I be next?”

The doctor shook his head. “The spear-head didn’t penetrate your skin, fortunately. In Arv’s case it went right into muscle, like a hypodermic needle.”

The others on board—Chow, Mandelia Akwabo, and Ryerson Cully—periodically looked in, trying not to be a distraction. In the lounge, forward of the infirmary, they sat and talked nervously.

“Great gallopin’ longhorns, I hate feelin’ helpless,” muttered Chow. “We got Hanson in there fadin’ away, an’ who knows what’s happenin’ to Tom out there!”

“I know what you mean,” said Ry. “All my life people have kidded me, and bullied me, because I have a sensitive disposition. It’s not as if I asked to be born with it! One tries to do the best one can.”

Chow asked Mandy, “Ma’am, you think that village chief is gonna help us?”

“It’s possible, if Craig convinced him that his people’s earlier hostility was based on a mistake,” she responded, standing next to the big curving window. “But it isn’t easy where pride is involved. These people have been effectively at war for a generation, and― ” She broke off suddenly. “Someone’s coming out there!”

It was now twilight and difficult to see, but the watchers could make out several shadowy figures approaching the ship.

“Four of ’em,” Chow murmured, squinting. He trotted back and informed Hank, who raced to switch on the craft’s exterior lights.

“It’s them—Tom, Bud, and Craig!” Hank cried. “And somebody from the village.”

Hank admitted his fellow crew members, who were followed by a villager decked out in a multicolored tunic and a feathered headdress, his cheeks, forehead, and chest bearing ceremonial scars. Tom introduced him as Tbokua, the head medicine man of the Maba settlement.

“Good grief!” exclaimed Hank to Tom as Craig led the visitor up the stairs. “You’re not going to allow that hocus-pocus character to work on Hanson!”

“Now jest a second there,” Chow retorted. “I seen plenty o’ these types in my day out west, and I seen ’em fix up more’n one feller when the docs had given up on him!”

“Also, it turns out he has a medical degree,” added Tom dryly. “And he’s completely familiar with the drug the Maba use on their spears.”

Sterling fell silent and followed the group up to the top deck, where Tbokua was shown to the infirmary.

Doc Simpson stood outside the door, watching. “These native African doctors understand more about jungle illnesses than we appreciate.”

“Did they give you any trouble?” Mandy asked Tom in a whisper.

“Not when they recognized us,” replied the young inventor. “But they made us wait outside the city limits while they fetched the doctor.”

Ikumu!” the tall native exclaimed and Craig said this meant “spear.” Tbokua walked over to Hanson’s cot. After a brief examination, the medicine man said a few words to Craig, then left the infirmary.

“What happens now?” Tom asked.

“He’ll be back shortly,” Craig replied. “He’s going to pick up a certain herb. Doc was right about the poison on the spear.”

“Did he explain the nature of the poison?” Doc Simpson questioned.

“No,” the flier answered. “The only one I know of is a kind used by the Pygmies. They extract a juice from the white flowers of the Madura plant. Dipping their arrows into this liquid makes them deadly.”

The shaman soon returned with a handful of herbs, which he crushed in a wooden mortar. Presently he had a small amount of green liquid. Nervously the explorers stood aside while the native mixed a few drops of it with water and forced it down Hanson’s throat.

“I hope we’re doing the right thing,” Tom murmured.

“It’s a chance we’ll have to take,” replied Doc Simpson. “Hanson is sinking fast.”

The medicine man sat on the edge of the cot, muttering certain phrases over and over, as if they were incantations. In a few minutes Hanson started to writhe on his cot. Unintelligible sounds came from his lips. The medicine man, however, seemed unmoved and merely continued to chant.

Tom and his companions watched fearfully, wondering if this strange combination of magic and medicine would cure—or kill!














THE EVENING had now become night. In the infirmary the medicine man continued his muttering and at intervals gave Hanson more of the potion.

“How is Arv?” Tom asked Doc Simpson at midnight. The doctor reported little change and Tom was heartsick. “If anything happens to Arv I’ll never forgive myself. I feel responsible for his condition. If it hadn’t been for my expedition, he’d be safe in Shopton.”

By two in the morning the tension was lifted somewhat when Doc Simpson reported that Hanson was no longer delirious, but was sleeping soundly. “That’s a good sign,” he said.

From the Maba village came the steady beat of ceremonial drums accompanied by chanting. Craig explained that the Maba believed Hanson’s illness had been instigated by the ancestral spirits in the mountain who wanted no interference. They were trying to appease them with their prayers.

Tom felt a lump in his throat at this show of camaraderie. No matter what religious beliefs a citified person might have, he could not show more sincerity or faith than these simple tribesmen.

Outside the Sky Queen groups of awed Maba villagers stood, waiting patiently for news of Hanson. Finally at six AM Doc Simpson suddenly stood up and leaned over his patient. “I think Arv’s coming out of it!” he whispered hopefully.

Word spread through the ship. Everyone on board rushed to Hanson’s bedside. The stricken man moved, lifting one hand to his face. A moment later he rubbed opened his eyelids part way, then closed them again.

“Arv!” Simpson called softly. “Glad you’re awake.”

“Doc? Doc Simpson? Wh-what happened?” Hanson asked, opening his eyes wide.

“You were poisoned by that spear you took, but you’re all right now. How do you feel?”

Hanson managed a wry smile. “Like I just swam the Atlantic Ocean underwater,” he said weakly.

“You’ll be as good as new in a few days, thanks to this man here,” said the doctor.

For the first time Hanson noticed the native shaman who had risen from the side of the cot and was edging silently toward the door. When Doc Simpson announced that he had saved Arv’s life, Tom wrung the medicine man’s hand fervently and Craig thanked him profusely in the Maba dialect.

“Wait!” Hanson called as the healer started out the door. “I want to thank him myself!”

Mandelia spoke to the visitor, who gave a few words in reply. Then Tbokua moved off without another word, a solemn expression on his face as if he were in a trance. When he reached the ground, he stalked off, his tribesmen following.

“I told him that you were grateful,” Mandelia said to Arv.

“And what did he say?”

“That you should pray regularly to the spirit-gods, and take a non-aspirin painkiller as needed.”

With the tension gone, everyone relaxed. Chow’s jovial spirits returned. “I’ll rustle up one o’ my specialty breakfasts fer Hanson,” he declared.

Bud grinned. “Give the poor guy a chance to recover first. We don’t want him to have a relapse!”

Chow gave Bud a dark look and stamped out of the infirmary so vigorously that the giant plane seemed to rattle. “And how d’you like your caterpillars, buddy boy?” he asked threateningly as he left.

Bud gulped. “Scrambled, please.”

But when mealtime arrived, Chow served orange juice, bacon, waffles, and tall glasses of iced cocoa in preparation for Tom’s first journey with Bud and Craig to the mysterious mountain. He also packed a kit of food to last for a couple of days if they should decide to stay away.

“Thanks, Chow,” said Tom, and grinned. “In return I’ll bring you back some containers of gas.”

“Some of that stuff what blows things up?” the cook gasped. Then, seeing the twinkle in Tom’s eyes, he added, “Brand my rusty spurs, if you ain’t as bad as that Barclay feller!”

Dr. Simpson plopped down at the table, rubbing his eyes wearily. “I’m glad I had a chance to witness that bit of native magic,” he said. “But I’m worried as to what we’ll do if the cure isn’t permanent. I wish the equipment failure hadn’t cut us off from the world so totally.”

“Haven’t you noticed that the lights are working, and steady?” said Tom happily. It developed that the mysterious electrical problem had completely disappeared hours before, and all equipment was working again.

“Like magic!” Bud muttered.

After hours of much-needed sleep the terrasphere tank section was driven down the ramp from the Flying Lab’s hangar and out into the clearing, leaving the sphere section behind. The boys climbed in and checked the equipment.

“Let’s go!” Tom urged, and a few moments later the great hoop-like treads began to eat their way through the bush. Tom and the rest took turns in the elevated turret-dome driving the tank, while those not driving occupied the larger quonset-hut-shaped compartment further back on the mobile platform.

“There’s a lot of rough terrain between us and the mountain,” Craig warned. “This could be quite a long trip.”

The vehicle surged ahead. Ravines, rocky surfaces, deep mud, forest, bush failed to halt their advance. By swiveling the ring-tracks parallel to the body of the tank, the entire vehicle was narrow enough to drive between the great tree trunks of the forest—and powerful enough to drive over the smaller brush. After a while the explorers came to a region of denser jungle. Tom shifted to a lower gear. Small trees and thick vines snapped out of their path or fell beneath the treads.

Eventually they came to what appeared to be a difficult upward slope. Its real steepness was obscured by heavy vegetation. Tom brought the tank to a stop.

“I don’t know whether to try that incline or not,” he said over the intercom, peering out the dome. “I’m going up it a little ways on foot.”

Tom climbed from the vehicle. “Watch out for snakes and wild animals!” Craig warned.

“Okay.” Tom’s eyes quickly swept the area in every direction and he kept his right hand on the holster of the small impulse pistol, or i-gun, he carried for protection, which was now operational again.

After forcing his way through the dense brush, he reached the incline. Making a careful survey of it, Tom felt that the tank could negotiate the ascent.

The young scientist turned to rejoin his friends, then froze in his tracks. Two yellow gleaming eyes glared at him from a tree ahead. Crouched on a low limb was a black female leopard! Anger—or hunger—in its eyes, the large cat was ready to spring!

There was no chance for him to escape and Tom’s first impulse was to raise his gun. But instead he remained motionless, thinking, I hate to shoot that beautiful specimen if I can avoid it. Though the weapon had a stun setting, its effect on animals was never entirely certain and might prove injurious..

The leopard was as immobile as an ebony statue, yet poised for the kill. Tom’s position was the same, but his heartbeat was fast. Would he regret having waited to make the first move?

The two continued to glare at each other. Tom almost felt as if he were being hypnotized. I mustn’t let that happen! he cautioned himself grimly.

Suddenly he realized that the situation had changed. It seemed that he had hypnotized the leopard! A moment later the big cat turned her back on him, jumped down from the tree, and loped off through the bush!

“Whew!” said Tom, not only relieved but amazed. He hurried back to the tank.

When the young inventor told what had happened, Craig rebuked him. “Man, you took an awful chance!”

“Oh no he didn’t,” Bud countered. “Tom is an old hand at hypnotizing the girls—even lady leopards!” Tom picked up an extra radiation helmet and pitched it playfully at his pal.

The explorers resumed their journey. The slope was ascended with remarkable ease and the tank negotiated the downgrade equally well. Tom was pleased with their progress.

Occasionally they caught fleeting glimpses of chattering monkeys and once they stared in wary fascination at a huge python coiled about a low-hanging limb. At one point an elephant came crashing through the jungle, and Tom remembered the tale of how his great-grandfather and namesake had used the original electric rifle to stop an elephant.

Shortly after eleven that morning the brush thinned out, then the vegetation vanished completely. A short distance beyond towered their destination—the mysterious “mountain of the spirit-gods,” Goaba. Its snow-capped peak soared up through a ring of cumulus clouds.

“What a sight!” Tom exclaimed.

“Snow above, fire below,” said Bud. “By the way, where is the crevice?”

“About a mile from here,” answered Craig. “I see a rock formation I recognize.”

Tom recommended that they put on their antiradiation suits before driving closer. The three climbed into them and adjusted the helmets. Then Tom drove forward.

“There’s the crevice!” Craig pointed to the right. A black, narrow gash cut between two big upthrusting rocks.

Tom brought the vehicle to a halt. The various types of self-sealing containers to collect the gas were unpacked. He divided the supply among himself and his two companions.

The three climbed out of the tank and Craig led the way to the narrow opening.

“So this is the crack we traveled halfway around the world to see,” Bud remarked, unimpressed. “It sure doesn’t look important.”

“Maybe not,” Craig responded. “But what’s going on underneath is mighty important.”

“Let’s get started with our job so we can find out,” Tom urged impatiently.

One by one the various bottles were positioned over the crevice. The vacuum-sealed containers had automatic valves. At the first sign of the gas a release would open them. The higher air pressure outside the containers would force samples of the gas inside, then the automatic device would reseal the vessels.

When the task was completed, Tom gazed at the row of glass, lead, and Tomasite-covered containers that bordered the crevice, all securely anchored down into the rock. “That should do it!” he declared. “I wonder how long we’ll have to wait.”

The group returned to the tank and removed the headpieces of their antiradiation suits.

“You don’t know how often the gas appears?” Bud queried Craig, gazing at the mountain.

“No,” he replied. “I was never able to establish a definite timetable.”

“It’s possible we’ll have to wait for days,” said Tom.

Morning merged into afternoon. Then the sun began to sink. Nothing had happened at the mountain.

“We’d better return to the Sky Queen,” said Tom. “I’m a little anxious about Hanson. I want to make sure the medicine man’s cure was permanent. We’ll come back in the morning.”

The containers were left in position while the three travelers backtracked along the swath they had cut through the bush and jungle.

Sterling ran from the plane to meet them. At the same instant Tom asked, “How’s Hanson?” and Sterling said, “How did you make out?”

“Arv’s fine.”

“No luck yet on our side.”

The following morning Tom, Bud, and Craig returned to the mountain, arriving about ten. “It really isn’t far when you don’t have to hack your way through,” Bud remarked.

They crossed the clear section of ground at the base of the mountain, deserted as a moonscape, and veered around a rocky outcropping, bringing their destination in sight. As the tank approached the crevice, Bud gave an involuntary gasp of surprise.

“Tom, the containers! They’ve disappeared!”













THE mysterious mountain had played her strange trick again! The containers for capturing the gas had vanished!

“This is the same crevice where we left those bottles, isn’t it?” Bud asked.

“It has to be,” Craig declared. “Don’t you guys remember those big rocks we just went around? And over there’s where we sat in the shade for a few minutes.”

Tom, disappointed, put on his antiradiation suit and got out of the tank. The others, similarly garbed, followed and they all walked closer to the narrow opening.

“This certainly is an enigma,” murmured the young inventor. “You’re absolutely sure, Craig, that the locals wouldn’t steal the containers?”

“Out of the question!” Craig replied. “As I told you, the mountain is strictly taboo and no Maba would dare come this close or he’d be banished from the tribe.”

“But maybe whoever took the containers isn’t a Maba,” Bud remarked ominously. “Boondah’s men are supposed to be hiding all through this jungle. And let’s not forget Hoplin and company!”

As Tom pondered the strange phenomenon of the mountain, Craig asked, “Do you think something could have caused the bottles to shatter or explode?”

“If they had,” Tom replied, “we’d see fragments lying around. But there’s not a scrap.” He stepped closer to the edge of the crevice and peered down into the black abyss. “My guess is that when the gas was released during the night not one of my containers was proof against it.”

“Good night!” Bud exclaimed. “Then nothing will store that stuff!”

“I have another idea I’d like to try,” said Tom, frowning. “But I’ll need some things from the Flying Lab.”

As the trio walked back to the tank, a massive shadow swept across their path as a low sound reached their ears. They looked up to see a small twin-engine prop-plane swooping low. The craft then turned steeply and flew out of sight without dipping its wings in salute.

“Who could that have been?” Craig asked. “The pilot acted as if he was spying on us!”

“Who could it have been? I’ll tell you who it was!—our enemies!” Bud snorted. “The plane looked like an American-built one. I’ll bet it’s the same one the policeman told us about.”

“And the same one that dropped those incendiary bombs on the village,” said Craig in agreement.

“There certainly was something fishy about that flier’s maneuvers,” murmured Tom. “Why would he fly so low over this particular spot? I’m going to notify the authorities when we get back to the Queen.”

They entered the terrasphere tank and Tom flicked the ignition. Nothing happened—the engine was silent!

“Oh no,” the young inventor groaned. “The taboo mountain gremlin has struck again. Everything’s dead.” Then a horrifying thought struck him. “And we can’t stay here, or we might end up the same way!”

“What? How so?” demanded Craig.

“I think this anti-electrical phenomenon is connected to the release of the antiproton gas,” Tom explained. “If it’s occurring now, that may mean the gas is on its way—it may even be issuing from the crevice right now.”

“Sure,” Bud agreed nervously. “Maybe we can’t see it in the bright sunlight. But if it gobbled up those containers, it’ll do the same to our antirad suits—and us!”

“Then what do we do, Tom?” Craig asked. “Abandon the tank?”

“We’ll have to, at least temporarily,” was the answer. “Hopefully the gas will be diluted enough in the air that it won’t hurt the tank—but we can’t be sure.”

The three expeditioners trotted across the barren stretch of dirt and rock toward the edge of the green jungle beyond. There they stopped amid the trees and vines and turned to look back.

“The tank’s still there, at least,” Tom said with relief.

Craig pointed out that they could not be sure that Tom’s theory was correct. “Maybe there’s no gas coming up right now after all.”

“Then it’s time for an experiment!” Bud declared. Bending down, he picked up a bit of a broken wooden branch, with some leaves still attached to it. Then he forcefully hurled it toward the crevice like the ex-footballer he was. The branch segment arced through the air, hit the ground, and bounced toward the crevice. For a moment, all was still. Suddenly the watchers jerked back as the branch burst into flame!

“What sort of fire is that?” asked Craig in awe. The flames had a weird, unearthly tinge and seemed to radiate from the wood as if under pressure. In seconds the leaves had turned to ash, the wood had blackened, and the branch had fallen to pieces. Then the pieces themselves seemed to shrivel and evaporate into thin air!

“It’s just like what happened in your lab the other day,” Bud said to his friend.

“Now we know,” said Tom. “But if we’re dealing with antiproton matter, everything should be affected—even rocks.”

“I see,” Craig said. “You’re wondering why the whole mountain hasn’t disintegrated long ago.”


At intervals Bud hurled more of his “test probes” at the crevice. For more than an hour, all were promptly incinerated. But finally one bit of wood smoked slightly but failed to burst into flame, and the next one was completely unaffected. “Guess this gas attack is over,” Bud said. “So maybe the equipment will work now.”

The three trooped back to the tank and clambered inside. Sure enough, the steam turbines turned over on the first try without hesitation.

Craig volunteered to drive, leaving Tom and Bud alone in the passenger cabin.

“You have that ‘genius at work’ look on your face, Tom,” Bud remarked. “Thinking about the gas, or our enemy?”

“Both, I suppose,” he responded. “I wish I’d brought along my electronic camera and taken a picture of that plane. I’d like to know if it was Hoplin or his pal.”

“Or the third guy. But maybe he has a special assignment.”

Tom shot his friend a teasing look. “Still suspicious of Craig? So far he hasn’t tried to poison us, or blow us up—as far as I know!”

Bud winced. “Fine. But I’m suspending judgment until the Hoplin gang gets itself caught.”

Tom gazed out one of the long slit-like windows at the passing foliage. “We’ll be defeated even without our enemy’s help if we can’t figure out how to protect the terrasphere from the disintegration effect.”

“Bet you have some ideas.”

Tom grinned. “A few. And this should help.” He pulled a small metal vial from his pack. “I scraped a sample from the rocks near where we left the containers, by the crevice. Did you notice how the ground seemed to be covered with a hard crust of bluish-white mineral?”

Bud nodded. “I guess so. It looked like some kind of calcium deposit—almost like chalk, but baked into a hard shell.”

“I’m hoping Ry can help me determine what it is,” Tom said. “I have a hunch it’s similar to the substance the tube from space is made from, which was able to contain the gas inside without reacting to it. I can’t even imagine what sort of atomic structure such a substance could have, but if we can crack its secrets we may be able to use it to coat Terry.”

Taking turns in the control turret, Tom and his companions drove back to the Sky Queen as fast as possible—which was fairly fast, as it was becoming almost a routine commute through the jungle! When they arrived, Hanson was strolling beneath a giant baobab tree. In one hand was Tom’s electronic telephoto camera.

As the three explorers descended from the tank, Hanson flashed them a wide smile. “I hope you don’t mind my using your camera, Tom, but when a queer-acting plane buzzed us I decided to snap a few pictures. I suppose the pilot wanted to find out what we’re doing here.”

Tom was overjoyed. “You’ve done us a big favor, Arv. I suspect that plane was doing some snooping.”

“I haven’t brought the pictures up on the screen yet,” said Arv.

“Let’s take a look.”

Tom took the digital camera and began to examine the images as they appeared on the camera’s monitor panel. The others crowded around him, looking over his shoulder.

“Here’s a good view of the cockpit,” Tom said. “Let’s enlarge and enhance.”

The result was electrifying! “Great Scott!” exclaimed Craig. “The man in the cockpit is Hoplin—the guy I knew as Karl Taylor!”

“Right!” said Tom grimly. “So our enemies are here!”

“I can’t make out the face of the fellow next to Hoplin,” Bud said, “but I’m willing to bet it’s his partner, Cameron! Or whatever his real name is.”

“This is serious,” Hanson commented.

“They certainly didn’t follow us for the fun of it,” Tom agreed, “and I’m sure they’ll try to make trouble.”

“If their plane is the mysterious one the police officer told us about,” Bud spoke up, “it may be hidden in this wild country. Too bad we don’t have the Kub or the good ol’ Skeeter to scout around in.”

Tom gave Bud a surprised look. “We do have the Sky Queen, you know!”

Bud laughed. “True!”

After greeting the other members of the party, Tom lifted off in the Flying Lab and flew around for an hour in an expanding-spiral pattern. But the expeditioners, all gazing down alertly, saw no sign of the mystery craft or any encampment that indicated Hoplin had a hide-out in the bush.

“What’s that group of buildings over there?” asked Ry Cully, pointing. “I thought the native village was off in the other direction.”

Mandy Akwabo replied. “That, my dear man, is the village of Hyaddongo. It belongs to the Onaris—enemies of the Maba, relatives of General Boondah. Lift up a few of those palm branches and you’ll find a nice stock of jeeps, guns, and bombs.”

“And maybe a hidden plane or two,” added Hank Sterling.

Landing again, Tom got in touch with his father, giving him all this information and asking him to notify the authorities.

“I’ll do so, Tom,” replied Damon Swift. “But as you know, no one but the Supreme Commander seems to hold much sway over Borukundi.”

Tom also told about his disappointing lack of progress so far on the capture of any of the gas. Then he asked for detailed news from home, finally signing off with a touch of homesickness.

Tom spent the balance of the day and evening in the laboratory sector of the Sky Queen with Ry and Hank, studying the rock scrapings he had brought back.

“This obstinate stuff defeats our every attempt at analysis,” huffed Ry. “I’ve never in my life seen this sort of interlaced crystalline structure. I can’t guess what keeps it from falling apart.”

“It reflects light,” observed Hank Sterling. “I mean, we see it. But the spectrometer readings look more like something from a kaleidoscope!”

Tom rubbed his chain thoughtfully. “In the stolen file, Dad and I quoted some speculation about entrained space-knots that might be― ”

“Now wait, Tom,” Hank interrupted. “What did you say? Space knots?”

The young inventor grinned. “Sounds funny, doesn’t it? And it’s just a theory—but it works out mathematically. The idea is that there could exist atom-sized ‘twists’ in the fabric of space itself, stable warps that would be resilient and self-sustaining, and would tend to braid or loop together.”

“Like chain mail in a suit of armor,” Ry put in. “I recall the article in question. One could conceive of a lump of such material—not matter as we know it, but literally woven space. It would be an entirely novel mode of physical substance, composed neither of bosons nor fermions, but with certain characteristics of each. A fantastic notion.”

Hank looked sheepish. “I’m afraid my background in particle physics is a little skimpy.”

The professor smiled, for one moment appearing almost suave. “Photons are bosons—packets of energy that do not interact with one another, or with anything else. Like angels, any number of them can dance on the head of a pin! Fermions are the particles of which matter is composed, filling space to the exclusion of other such particles. They are quite different, you see. Of course, so-called ‘fermionic condensates,’ with mixed properties, have been created in the laboratory; but stable, enduring particles of that nature is the stuff of dreams, as it were.”

“Well, we may have it right here!” Tom said excitedly. “And because it isn’t made of matter at all, it wouldn’t be affected by antimatter.”

Hank agreed that the strange idea deserved to be thoroughly explored.

Eventually the others left for supper, and then for sleep, but Tom soldiered on in the metallurgical laboratory of the giant craft. Isolating himself, he worked feverishly to determine the bizarre properties of the material.

With barely time out for a snack, Tom worked far into the night. Finally, near dawn, Bud and Craig insisted that he rest for a few hours.

Smiling, he said, “Just to keep peace with you guys I’ll go to my bunk awhile for some shut-eye.”

At daylight Tom resumed work. For him the day passed quickly, as he tried experiment after experiment. Again when night came, there was another intrusion by Bud and Craig.

“You two are like a couple of mother hens,” Tom remarked, laughing. “But I suppose I owe you an explanation. The space-knot idea has held up well so far. I’ve been trying to concoct a paint for covering containers. So far, I’ve had no success.

“Do you think you’ll solve it?” Craig asked.

“I will!” Tom declared in a defiant tone. “Next, I’m going to try a paint using a gelatin base. To the gelatin I’ll add a portion of the finely ground rock. The combination will be a colloid. With luck, it might work!”

A long day became a restless night. At eight o’clock the following morning Tom continued his work. During the course of the day, various other members of the expedition traveled via the terrasphere tank to the taboo mountain, always taking great care to determine whether the antiproton gas had erupted. They returned with large quantities of the bluish-white rock substance. Hours went by but Tom knew now that he had the right consistency of paint, although the problem of drying still confronted him. At last, however, with the addition of some Tomasite he found the answer.

Excitedly he called in all the members of the expedition. “I think I have it!” he said. “Now I’ll put new containers to the test. Hank and Arv, will you help me make half a dozen of them and I’ll paint the containers inside and out, then bake them to get a smooth surface. In the morning we’ll go back to the mountain.”

“Well, brand my empty bean cans!” exclaimed Chow. “Tom Swift, you’re smarter’n a pack o’ prairie wolves—and that’s mighty smart!”

The others added their congratulations, but Tom held up a hand. “Save your praise until the experiment has been completed,” he urged.

“Your dad will be thrilled to learn this,” Arv Hanson remarked.

“I’ll talk to him as soon as I learn a little more about the nature of the gas itself,” Tom said.

As night fell, Tom enjoyed a hearty supper with his fellow expeditioners for the first time in days. Chow only smiled when asked what had gone into the odd-colored casserole that he had prepared, but it proved to be delicious nonetheless.

At the table Doc Simpson discussed some of his own experimental work, in which he had been engaged as circumstances permitted since the arrival.

“There’s quite an unusual selection of rare herbs and plantlife in this little corner of Borukundi,” he explained. “Tom, do you suppose the radiation from Goaba might be producing mutations in this area?”

“The radiation level is completely normal around here,” was Tom’s reply. “At least that’s the way it is now. But it may be that the levels were much higher in the past. What we’re seeing may not be new mutations, but the descendants of old ones.”

Simpson nodded his agreement. “Yes, that makes perfect― ”

His comment was masked by a loud crash rolling down the central corridor from further aft in the ship.

Chow groaned. “That better not be comin’ from my kitchen!”

“More likely the infirmary,” muttered Doc Simpson, rising to his feet with the others.

A figure appeared striding briskly down the corridor toward them. “Professor Cully!” cried Mandelia Akwabo. “Is something wrong?”

Ry Cully paused, blinking in the light. “Tom Swift!” he thundered. “What about the banana?”

Tom’s jaw dropped. “Did you say― ”

The gray-haired geophysicist broke out in raucous laughter! “No, my love is like a red, red… “

The last words were choked off. Cully’s legs gave way and he collapsed to the deck!








          BIG GAME





IN THE infirmary of the Sky Queen, Doc Simpson frantically examined the unconscious geophysicist.

“His vital signs are all right,” the medical man said to the onlookers crowding the door. “I’ll be darned if I can figure out what’s causing this.” He looked up, frowning, and caught Tom’s eye. “You know, I’d almost diagnose Cully as falling-down drunk. Could that be possible?”

“We have no alcoholic beverages aboard the ship,” Tom stated.

“Not even cookin’ sherry,” Chow added.

“Besides,” said Hank, “I’ve gotten to know Ry fairly well over the last week—he’s hardly the drinking type. Doesn’t even drink coffee or soft drinks.”

“I don’t smell any alcohol on him… ” Simpson passed a hand over his eyes. “You know—I’m starting to feel… “ He paused, then looked at the others blankly. “What was I saying?”

“Better set yerself down, Doc,” urged Chow. Suddenly he chuckled. “Now thet’s a fool thing fer me t’say—he’s already settin’. That bell, though… s’makin’ me a mite… “ The big cook sagged against the doorframe, trying to hold himself up.

“The air!” gasped Tom.

“What about her?” asked Bud waveringly.

Tom struggled to speak coherently. “She—I mean, it—something—everybody run! Go!”

Leaving Cully in the infirmary, the others staggered a wobbly path back to the dining area, where Tom switched on powerful fans to draw out and replace the air. They began to feel better almost instantly.

“What in the world happened to us?” mumbled Mandy. “My head is throbbing… and that smell!”

Bud wrinkled up his nose. “I didn’t notice it before, but I sure do now! Man, it’s like somebody emptied a whole bottle of cologne on the carpet—Tropical Nightmare!”

Yet Arvid Hanson was mystified. “I don’t smell a thing!” he protested.

“You weren’t affected mentally, either,” commented Tom. “Whatever this is that we’re reacting to, you’re immune to it, somehow.”

“Could someone be pumping a gas or drug into the Queen from outside?” asked Craig.

Tom shook his head. “The instruments are sampling the air constantly for outside impurities, and it’s well filtered. This must originate inside the plane.”

Bud mentioned the crash they had heard. As he seemed unaffected, Arv walked back down the corridor, first to the galley, then through the infirmary. He returned holding a small glass flash with a stopper in its neck. The flask was cracked on one side.

“This was lying on its side under one of the shelves in the infirmary,” Arv reported.

Simpson took the flask from Arv’s hand to examine it closely. Immediately he winced. “Phew! You don’t smell that, Arv?”

“Not a bit!”

“This flask contains one of the samples I took earlier today. I must’ve carelessly set it on the edge of the shelf.” He glanced at some black markings written on the flask. “Now I recall—it came from some bright pink flowers that the insects seemed to be avoiding, though they looked the same as all the others. I didn’t notice any particular odor then, but― ”

“Now’s a different story!” choked Craig Benson. “It’s awful!”

“Guess we’ve found the culprit,” Tom said.

“This may be one of the ingredients the people of the Maba village use on the tips of their spears,” mused Doc Simpson. “It must generate a vapor that affects the central nervous system. Say, that could be why Arv is immune—the shaman’s treatment must provide a degree of protection.”

“Wa-al, get rid o’ that skunk juice!” begged Chow, holding a gaudy bandana to his generously sized nose.

“Not on your life,” responded the doctor. “This could be a great discovery. But I’ll bag the flask so the vapor will be isolated.”

Meanwhile Ry Cully had regained his feet and stuck a woozy head into the corridor. “What’s the excitement out there?” he demanded. “What am I doing in the infirmary?”

“What’s the last thing you remember, Ry?” Tom inquired.

“I heard a sound in the infirmary, and went in to take a look. I seem to recall… something on the floor, and― ” He frowned in perplexity. “Something about a banana.”

“That there’s powerful stuff!” muttered Chow to Tom.

The next morning Tom, Bud, and Craig prepared for their trip back to the mystery mountain. They worked steadily in the clearing next to the Sky Queen, stocking the terrasphere tank for the next phase of the project.

“This time,” Tom declared, “we’ll stay at the mountain until the phenomenon takes place.” He had packed away a number of the new containers he had fabricated, coated with the antiproton-resistant material, before breakfast. Then, in the light of a pale sunrise, he had carefully sprayed a coating of the protective stuff over every inch of the terrasphere tank, as well as the descent sphere itself, which had been unloaded into the clearing but was not yet emplaced on the tank platform, as it would not yet be used. In honor of its peculiar immunity to matter-antimatter reactions, the young inventor had conferred the name Inertite upon the coating substance.

“What if the magic gas shows up in the middle of night?” Bud asked. “Should we go on guard duty?”

“None of us need lose any sleep on that score,” the young inventor replied, smiling. “I’m attaching a miniature radio transmitter to the automatic valve of each container. When the valves open a signal will be sent out. It’ll set off an alarm inside our vehicle.”

“Very ingenious, Ingenious Boy!” Bud commented. “So if the alarm goes off, we’ll get some kind of answer to this mystery. I don’t suppose there’s a ‘snooze button’ for the alarm—in case we want to catch a few more winks?”

“Sorry!” Tom laughed. “By the way, we’ll take the earth blaster along. I may do a little digging to see what the mountain is made of further down.” In response to an expression of curiosity by Craig, Tom described the earth-borer machine he had invented. This special small model would not drill by vaporizing the material in front of it, but would use diamond-hard hypersonic vanes capable of reducing solid rock to dust. Specimens would accumulate in a small container at the rear of the device.

“All the vittles are loaded,” Chow announced presently. “Enough fer a week, five meals a day. Mebbe you all won’t have nothin’ else to do but eat fer a while.”

“Thanks,” said Tom. “I’ll radio if we decide to spend more than one night at the mountain, though.” Then he turned and yelled out, “All aboard!”

At that moment a terrifying ragged roar came ripping through the nearby trees. “A lion!” Bud cried.

“I thought I heard someone’s voice too!” said Tom. “Maybe he’s in trouble!”

Tom ran to the edge of the clearing and peered off into the dense jungle bush. A second roar was followed by the crack of a rifle and the whine of a bullet. The missile tore through the sleeve of Tom’s jacket! As he looked down at the hole in stunned surprise, Bud’s muscled arms closed around him, pulling him aside to safety. As the youths dodged behind the trunk of a tree, another shot ricocheted off the bark.

A third bullet came whistling past Tom, this time from behind. The tree trunk was no longer a shield! Tom and Bud threw themselves to the ground. Still more shots rang out. Chunks of bark exploded from a tree just behind the young inventor. Then at last all was quiet.

Tom heard worried shouts from the Sky Queen, and from Craig Benson, who had sought cover behind the terrasphere tank. But Tom and Bud remained in their prone positions, listening. They could detect the faint sound of snapping twigs. As the noise grew louder, Tom watched intently. He thought he could hear the deep, heavy breathing of a lion—or was it imagination? Some of the brush began to swish violently. Someone, or something, was approaching their camp!

A few seconds later a husky figure, wearing the traditional tan-and-khaki clothes of a big-game hunter and holding a rifle in readiness, stepped from the brush into the clearing. To Tom’s surprise, the hunter proved to be a woman.

Tom cautiously rose to his feet, ignoring Bud’s hissed protest. “What’s the idea of shooting at me?” he yelled angrily.

“Oh, hello there! Do you mean one of my shots nearly hit you?” the hunter gasped.

“More than one. What were you trying to do?” Tom pointed to the holes in his shirt sleeve and the shattered bark of the trees.

“I must apologize!” the stranger replied. “I wasn’t aware there was a camp here. When that lion came toward me, I just kept shooting! Whuff! Guess I scared him off. But this settles it! From now on I’ll leave big-game hunting to the experts. Why, goodness, I might have killed you!”

Bud, unable to remain quiet any longer, retorted, “You sure might have! You’d better leave that rifle here, lady.”

The woman, tanned and somewhat burly, glared at Bud. “The name, young man, is Ophelia Wootenscarp.” Bud took a half-step backward—the woman still held her gun, after all!

“I’m Tom Swift,” said the young inventor coolly, then introduced his friends. “Are you in Africa for sport?” he asked the hunter.

“No, no,” she replied. “I accepted a position with a small company here that transported cacao down the Congo River for export. After a year, the firm went bankrupt. I decided to stay for a few months, experiencing the real Africa, before returning to my tame and dreary life in England.”

Miss Wootenscarp scanned the explorers’ camp. She marveled at the Sky Queen and at Terry. “You have quite an operation here. My word! I don’t suppose I might catch a ride with you?—to America would be quite satisfactory.”

“I’m afraid not,” Tom answered.

“Yes, well, very good then. In that case I’ll be shoving off,” she said. She slung her rifle over her shoulder and was soon lost among the trees.

Tom went to change his shirt. When he returned, Bud said, “Maybe the heat has got me, Tom, and I know you already think I’m too suspicious, but― ”

“Frankly,” admitted Tom, “I feel the same way. Her story sounded fishy to me. I can’t imagine anybody going on an African hunt without a guide.”

Craig concurred. “And her rifle! It was an old Model 270. That’s a poor choice of caliber for brush country.”

“Seems like t’me she ’as jest play-acting,” was Chow’s comment. He had come out of the Flying Lab after the shooting had ceased. “That there phony ‘pip-pip’ accent o’ hers—brand my silver spurs, ain’t nobody who really talks like that!”

The young scientist instructed Sterling and the other men not to give out any information concerning their expedition if the stranger should return. Then the journey in the terrasphere tank to Goaba, the sacred mountain, was finally begun.

With the route flattened, Tom made the trip in record time, arriving well before noon. Craig and Bud aided him in placing a few of the containers he had brought next to the crevice. Then they returned to the air-conditioned passenger cabin.

“Make yourselves comfortable,” Tom advised, picking up a science magazine. “It might be a long wait. But we’d better keep on our antiradiation gear, except the helmets.”

“You’re pretty sure the Inertite coating you sprayed on Terry will do the trick,” remarked Craig.

Pretty sure,” Tom grinned. “But you’ll notice I’ve parked well away from the crevice!”

They lunched comfortably, waiting for the signal from the containers to announce the presence of the gas. Tom glanced at his elaborate wristwatch, a gift from Bud. “One eighteen,” Tom announced. “I’m predicting we’ll get the signal in about six minutes.”

“How’d you figure that, Sci-Fi?” asked Craig.

“Let’s see if it happens,” Tom answered. “Then I’ll tell you.”

The six minutes passed—seven—and the buzzer in the cabin remained silent. “Oh well, it was just a guess,” commented Tom, disappointed. “I’ll explain what I― ”

The buzzer buzzed loudly!

“Thar she blows!” cheered Bud.

Three pairs of binoculars were trained on the crevice, which was about 200 feet distant. The small containers could be seen resting placidly in the bright midday sunshine.

“Keep your eye on the one marked in red,” Tom advised. “I gave it only a thin coat of the Inertite paint.”

Even as he spoke, the container indicated began to glow with a strange fire, visible even in the glare of the sun. A weird yellowish steam seemed to rise from it. Then, in an instant, it began to melt down in a shower of sparks, until only a shapeless lump of blackened metal was left.

“But it didn’t disappear completely!” exulted Tom. “So even a thin layer of paint provides a degree of protection.”

“And the other containers aren’t affected at all,” noted Craig. “Looks like we’re in business!”

“But how did you know when the gas would be released, Skipper?” Bud inquired.

Tom leaned back happily in his padded chair. “I looked at the data we had on the times of the eruptions, and realized a pattern was starting to emerge. The eruptions were taking place twice a day, at equal intervals. So what is it that happens twice a day like that, rain or shine?”

“What?” asked Bud.

“The tides!”

“But Tom, we’re nowhere near a body of water out here,” Craig objected.

Tom explained his theory that the underground source of the antiproton gas was linked to a subterranean channel, or series of channels, that ultimately led to the Atlantic Ocean hundreds of miles distant. “At high tide, a wash of water floods into the channels and eventually reaches the mountain—about forty minutes later, it arrives. The seawater starts a chain reaction that leads to the production of the gas.”

“Then that crack in the side of the mountain must lead down into the ground, maybe to some big cave or pit,” Bud mused, looking out the window.

“Probably a system of interlinked caves,” Tom declared. “Like a volcano—but instead of molten rock, these are caves of nuclear fire!” He rose to his feet excitedly. “And I’m determined to explore them!”















THE AUTOMATIC stopper mechanisms on the specimen containers also allowed Tom to remotely monitor the presence of the deadly gas. After the better part of an hour, the young inventor pronounced it safe to leave the tank, though all three were to wear Inertite-coated suits and helmets.

They slowly approached the crevice and found that all the protected canisters were unharmed and sealed. “Finally!” Tom exclaimed. “Now I can study the gas with the Flying Lab’s equipment.”

After stowing the containers in a special shielded locker, the travelers removed the small mechanical earth blaster from the terrasphere cradle, where it had been lashed down for the trip. Though the torpedo-shaped device was only four feet in length, it was quite heavy. Even though Tom had driven the tank to the very base of the slope containing the crevice, lugging the blaster up the incline had all of them perspiring freely.

“Man!” Bud complained. “These labor-saving devices sure require a lot of labor!”

Finally the three withdrew to a safe distance and Tom activated the machine. A deep roar soared in pitch to a shrill whine, and then became inaudible. Feeding power to the blaster’s wheels, Tom watched excitedly as it tipped nose-down and bored into the rock immediately next to the lip of the crevice, heading downward at a sharp angle.

Minutes passed. Suddenly the rock beneath their feet began to vibrate! Tom immediately shut off the blaster’s rock-pulverizing mechanism and reversed the traction-wheels, backing the machine up and out of the clean hole it had created.

“Look at that!” Craig exclaimed. The digging vanes had dissolved away, leaving only a nub behind!

“Didn’t you coat them with Inertite, Tom?” Bud inquired.

The young inventor ruefully slapped his forehead—a symbolic move, as his transparent helmet was in the way—and groaned, “Sure I did, but I forgot that the thrusting action would rub the coating right off!”

Bud asked his friend if there was a way around the problem.

“Eventually, of course, we can bring the big atomic model here and melt our way through,” Tom replied. “As for now …” He thought deeply for a moment, then walked over to the hole the blaster had dug, peering down.

“See anything?” asked Craig.

“I think the blaster might have broken through to something. I’ll bet it’s an underground pocket of the gas, which is what disintegrated the vanes.” He looked up, suddenly enthused. “Guys, we could use explosives to widen the hole enough to lower the descent sphere into it!”

Bud boggled. “Hey, it’s not like I don’t like blowing things up, but do we even have explosives?”

Tom mimed snapping his fingers. “I can make some.”

“I should have known!” said Bud.

They carried the ruined earth blaster back to Terry, where Tom labored in the shade of the big vehicle to disassemble the blaster and remove the set of solar batteries that fed it power. He drained several different chemicals from the battery cells into some extra specimen containers, then carefully measured some of the fluids into a transparent flask.

As Bud and Craig looked on nervously, the liquid mixtures began to bubble and fizz violently, and the fluid turned milky white. After two minutes most of the liquid had boiled away, leaving only a small mound of yellowish crystals at the bottom of the flask, which Tom sealed firmly.

“How long before it blows up, chief?” asked Craig with a worried frown.

“Oh, it’s perfectly stable by itself,” the young inventor replied. “But listen to my plan, guys. We know the rock below must be densely laced with veins of Inertite—or it wouldn’t be here in the first place. Now these acidic crystals will react with Inertite, in effect dissolving it. And it’s my scientific guess that reducing or adulterating the Inertite will cause the solid rock to crumble under its own weight, creating an opening into the caves beneath!”

“Okay, pal, but you’re surely not planning to sprinkle that stuff around by hand, are you?” cautioned Bud.

Tom smiled and said: “Watch!” Using some adjustable clamps and rods from Terry’s tool locker, Tom constructed a simple tripod framework which he positioned very precisely over the hole dug by the earth blaster. Then he hung the flask of crystals from the peak of the tripod at the end of a smooth, slim cord, leaving the flask suspended neatly over the center of the hole. He then slowly played out the cord, walking backwards, until he reach the terrasphere tank, where he tied it to part of the locking mechanism on the cradle for the descent sphere.

“Man, I get it!” said Craig admiringly. “When you flip open that locking clamp, the cord will slip free― ”

“—and the flask will drop down into the hole,” Bud finished.

“That’s the idea,” Tom confirmed. “The fall looks like a good fifty feet. I’m sure the flask will shatter and spread the powder into the air. That should be sufficient to get the reaction going.”

The expeditioners withdrew into the safety of the tank. Tom climbed into the control turret, watching intently through the observation dome as he flicked the switch that would release the cord.

“There goes the flask!” Tom intercommed excitedly. “Shouldn’t take more than a few seconds for― 

But Tom’s prediction was shown to be wrong before it had even escaped his lips, for at that moment twin tongues of blinding white flame came roaring up through the blaster’s tunnel and the mountainside crevice. A walloping thunderclap accompanied the eruption.

Oops!” murmured Bud. “I don’t think this is what genius boy had in mind!”

The ground beneath the tank vibrated like a struck bell—vibrations which increased rapidly to earthquake scale!

“Hang on!” Tom intercommed from the control dome. “We’ve got to get out of here!” He gunned the engines and the tread-rings began to rotate. But even as the vehicle began to crawl forward, Tom, Bud, and Craig gasped in shock as the entire side of the taboo mountain fell away, collapsing into the bowels of the earth all around the crevice!

The edge of the black opening rolled toward them like a hungry thing as more and more rock fell away. One second more and the hard ground beneath the struggling tank also collapsed, and Terry began to slide helplessly down a steep, rocky incline.

In the turret Tom tried to steady himself with his left hand while his right hand leapt over the controls. He knew that Terry’s powerful supergyro would keep the platform from flipping over. But if the sides of the chasm were to fall in on them, there would be no chance of survival.

Suddenly they were swept into darkness. The broadening gouge had become a steep-slanting tunnel carrying them helplessly forward into the earth.

The metal shell of the tank rang with the impact of rocks of all sizes and shapes, from pebbles to car-sized rolling boulders, and the air was thick with black dust.

The wild slide seemed to last a long time. But at last Terry clanged to an abrupt stop, wedged sideways between the rock walls of the channel.

“How’s everyone doing?” came Tom’s panting voice over the intercom.

“A few bruises,” replied Craig. “Otherwise, not so bad.”

“Skipper, what happened?” Bud asked in a weak voice.

There was a long pause. Then Tom slowly replied, “I guess we can call it an unexpected experimental result. The crystals I made didn’t just interact with the Inertite in the rock, but with residual traces of the antiproton gas itself. And when proton meets antiproton—!”

“Yeah,” said Craig. “And here we are.”

After a few minutes, Tom decided it was safe to exit the control turret and cross the platform into the passenger cabin.

“How badly are we damaged?” Bud asked fearfully.

“Not badly at all,” said Tom, “according to the instruments and what I was able to see. Remember, this spelunker-clunker is designed for dealing with rocks and rough spots.”

“Then she must feel right at home,” commented Craig sourly. “Can we climb back up the slope to the surface?—with or without the tank!”

“I’m fairly sure we can turn Terry around and work our way back up,” responded the young inventor.

Bud saw the gleam in his pal’s eyes and said, “But that’s not what we’re gonna do, is it.”

“Oh, we will.”

“But not now?”

Tom shook his head, and his voice was alive with excitement. “Nope! Not just yet. Haven’t you two taken a look outside? There’s a whole new phenomenon for us to look into—and we’ve got hours to do it!”














“HOURS TO do it, huh,” said Craig Benson skeptically. “You mean, hours before the antiproton gas comes rolling up the shaft and disintegrates us.”

“Relax,” Tom said calmly. “We’ve already proven that the Inertite coating is enough to protect us from the gas. I’d prefer to be above ground before the next eruption, but it isn’t essential.”

“You’re the man in charge, Tom,” said Bud pointedly, and Craig nodded in compliance. “But what’s the ‘whole new phenomenon’ you mentioned?”

“Phosphorescence,” replied the young inventor. “The rock walls are glowing! It’s very faint, but you can see it—and I want to know what’s causing it.”

After the three circled the vehicle with flashlamps, Tom was satisfied that he could free the tank from the mound of displaced rock that had jammed it against the jutting cave wall. Returning to the turret he threw the treads into reverse, simultaneously shifting the axis orientation of the inner rings so that the treads would bite into the walls. The mechanism proved its worth. In minutes the mobile platform was free to move.

They were in a narrow, high-sided cave of whitish rock, which had apparently linked the crevice to the mysterious source of the gas further below. By occasionally riding the tread-rings up onto the curving walls, it looked as though Terry would be able—barely—to proceed onward and downward.

“Let’s get going!” urged Tom. “The whole secret of the mysterious gas might be at the end of this cave.”

Craig objected. “What if Hoplin and his partner are hiding near here?” he warned. “They could seal the cave entrance with a few sticks of dynamite!”

“Why not post one of us as a guard?” Bud suggested. “I can climb back up to the surface if you want, Tom,” he offered.

“One man wouldn’t be enough against Hoplin’s gang,” Tom reminded his friend. “Look, while we’re down here discussing the question, we could be doing some scouting that will help us later. Let’s just go a bit further and see what we can see. Then I’ll back Terry all the way up to the top, if we don’t find a place to turn around in.”

Craig laughed. “Sci-Fi, I’d be a lunatic to try to stop you when you’ve got a whiff of scientific discovery in that nose of yours.”

As the tank eased forward into the cave, Tom, Bud, and Craig tingled with anticipation. The last faint traces of bright sunlight were left far behind. The vehicle’s searchlight stabbed the inky darkness.

“The floor of this cave is reasonably level,” Tom remarked over the intercom. “I think the uprushing gases must have a scouring, smoothing effect on it, like sandpaper.”

“Let’s hope it stays that way,” said Craig, “and that the tunnel stays big enough for us to get through.”

“Even if we have to wiggle now and then like a worm!” Bud added.

Minutes passed as the terrasphere tank penetrated deeper and deeper into the mysterious corridor. Eventually the explorers arrived at a sharp bend. Tom, about to make the turn, brought the vehicle to a stop so abrupt that it slid several feet.

“What’s up?” Bud intercommed.

For answer, Tom snapped off the spotlight. A ghostly light, much brighter than before, was shining from around the bend.

“Jumping jets!” Bud cried breathlessly. “That glow! It must be from the gas!”

Tom did not agree. “High tide isn’t due for several hours!” he said.

As the explorers stared at the weird glow ahead, Craig suggested fearfully that there might be other people in the cave.

“Not Hoplin and Cameron,” remarked Tom. “They’d greet us in darkness and pull a fast one.”

Tom still was inclined to think that the ghostly light was a natural phenomenon of the taboo mountain. With this thought in mind, he sent the vehicle forward and rounded the turn.

“Wow!” gasped Bud. “What a sight!”

The cavern walls were glowing with a strange, shimmering phosphorescence. Every bit of rock surface seemed to be aflame with a cold, green-white light. Tom and Bud were instantly reminded of the luminescence they had observed in Tom’s laboratory in Shopton.

“Remarkable!” said Craig, “But it’s sure eerie. What do you think is causing the cave to glow, Tom? Atomic radiation?”

“It must be a secondary reaction to the antiproton gas,” the young scientist theorized, “perhaps an effect of the Inertite particles in the rocks.” He explained that if the atomic structure of the rock were being excited—pumped full of energy—the release of the energy overload could produce such an emission. “And the walls are definitely radioactive,” he said after checking the instruments. “You wouldn’t want to stay down here for too long without antirad protection.”

Greatly intrigued by the phenomenon, Tom continued ahead. The corridor of glowing rock stretched for a considerable distance, then stopped abruptly, ending at a solid barrier of rock.

“End of the trail,” Bud muttered somberly.

“Maybe not,” Tom retorted optimistically. “I’m convinced we’re getting near the source of the mysterious gas. Perhaps it’s originating from a subterranean pit on the other side of that wall. It looks to me that this barrier is new—another effect of my little explosive experiment.”

“Pal, you don’t intend trying to dig through this wall?” Bud asked in amazement.

“Not yet,” Tom replied. “First, I want to make some careful measurements. It may help me pinpoint the source of the gas. Next time we can come back with real digging equipment and punch our way through.”

“Then let’s go!” said Bud. He had gradually become as nervous as Craig about the possibility of danger.

“Just a minute,” Tom replied. He checked his suit and helmet. “I want to collect some specimens of this rock to study back in the Sky Queen tonight.”

“You couldn’t just read a magazine?” Craig gibed wryly.

Tom climbed out of the tank, carrying a pick. Soon the cave was filled with the sound of digging as he cut deep into one wall. Each stroke tore out big chunks of the rock.

“This should be enough,” Tom said as he handed up half a dozen pieces to Bud and Craig. “Load these into the cargo bins, will you?”

Tom studied the rock wall for a few minutes more, then climbed back inside the tank, heaving a reluctant sigh. Glancing at the clock on the dashboard, he noted, “High tide is still hours away, but we don’t want to play it too close.”

Along the way the terrasphere tank had passed through a wider section of the tunnel. They backed up to this point, and by skillful maneuvering Tom found space to turn the tank completely around. The explorers started their journey out of the cave. Piloting Terry, the young inventor sat in deep thought, wondering if the rock specimens would furnish him with some answers to the scientific puzzle of this cave of the spirit-gods.

“We’re almost out of the cave!” Bud announced at last, seeing a disk of sunlight ahead. In moments Terry surmounted the last pile of rocky rubble and tumbled out into the blinding afternoon sunshine.

“Don’t know about you, Bud,” Craig murmured, “but I’m mighty glad to see the sun again.” The younger pilot agreed.

They gathered up what was left of the equipment that went with the atomic drill, which had been stacked in the clearing and appeared undisturbed, then drove to the Sky Queen camp at impatient speed.

Hank Sterling came ambling up as they piled out of the tank. “Decided not to spend the night, eh?”

“Where we went, they’ve got nothing but night!” joked Bud. In the lounge aboard the mighty ship Tom and his friends narrated the story of their unexpected adventure.

“Young man, you are quite a taker of risks,” Ry Cully said in a stern voice. “Do give thought to the fact that if anything happens to you, the rest of us will be in serious difficulty.”

“Oh, don’t worry, Professor,” said Doc Simpson with a wink at Tom. “If anything knocked Tom, Bud, and Craig here out of the picture, commanding the Sky Queen would fall to a man of considerable maturity and travel experience.”

“Who?” demanded Ry. “Sterling?”

“Chow Winkler!”

Chow played along with the joke. “Sure enough! And I’ve had many a year o’ experience with vehicles ten times more rambunctious than this here Flyin’ Lab! An’ they kin buck, too!”

Professor Cully gave a sheepish look and joined in the laughter.

The blunted earth blaster was carried into the Queen’s engineering workshop, which adjoined the hangar hold on the bottom deck. Tom at once took inventory of his supply of spare parts for the earth blaster, and was relieved to find that he had enough to construct another drill-head.

“This is how we’ll be getting through that wall,” he told Craig, who was helping him.

“Won’t those penetrator vanes just dissolve again?”

“I hope not. On the drive back I thought up a better way to anchor the Inertite coating to the metal of the blades.”

Bud, together with Hanson and Sterling, worked in the Sky Queen’s machine shop to clean and recondition the damaged earth blaster. Another heavy coating of Inertite served as the finishing touch. When joined to the new drill-head and tested on some boulders at the edge of the clearing, the new unit functioned as well as the original one.

“We’re all set now,” Tom announced wearily, wiping his brow. He felt eyes on him and turned. Chow was standing by the hatch ladder, a disapproving expression on his face.

“Something wrong, Chow?” asked Tom.

“Boss, if’n you’ll pry open them eyelids o’ yours, you’ll see that it’s night out—them lights up there is stars.”


“So when’d you plan to eat? Or t’ let Bud an’ Hanson and all the rest feed themselves?”

Surprised, Tom turned to Arv Hanson, who was helping Craig pack away the earth blaster near the test boulder. “Arv, Chow says it’s night. You’re not hungry, are you?”

Hanson laughed. “Tom, I could use a Hippo sandwich right about now!”

“We can’t all draw on scientific curiosity as a power source, Sci-Fi,” admonished Craig sympathetically.

Much embarrassed, Tom agreed to take a break for a late evening supper.

“I know’d you’d say that,” remarked Chow. “So I got it all prepared an’ ready on t’ other side o’ the ship.”

“You mean outside, in the open?”

Chow snorted humorously. “Yew cain’t have a good barbecue on th’ inside, now kin you?” It developed that the talented range cook, with the help of Mandelia Akwabo, had worked out trade relations with some of the less conservative Ogaphabu villagers. “We been tradin’ cooking secrets,” Chow declared. “An’ they gave me some fresh meat and fruits and all kinds o’ vegetables, so’s everything in my recipe is the gen-yoo-ine article.”

Bud pretended to flinch back in fear. “Did you run the ingredients past Doc Simpson? I want to live to see another sunrise!”

“Buddy boy, one of these days I’m gonna take you serious and head back to Texas,” responded Chow. “’N then you’d miss me fer sure!”

Bud chuckled. “Pard, without you, I’d be down to skin and bones in no time.”

Chow’s barbecue supper under the stars was indescribable—yet completely delicious. The expeditioners sat comfortably on a big tarp spread out over the ground beneath the forward curve of the great fuselage, where they could look out through the trees and see a purple-black sky glimmering with a million crystalline stars.

“This is wonderful,” Doc Simpson murmured. “Even in the twenty-first century, there’s still at least one spot on earth with air that’s fresh and pure.”

“Don’t mention it to Tom,” Bud joked. “He’ll try to squeeze it into a tank and ship it back home.”

As the others relaxed in the warm night air, Tom and Ry Cully boarded the Sky Queen to make a preliminary study of the gas that had been caught in the shielded containers. It was released with great care into an Inertite-coated test chamber which was studded with various sophisticated electronic instruments and sensor devices. The results of the initial test revealed some startling facts. The gas proved to give off antiprotons, as Tom had suspected, but he was amazed to learn that it contained traces of a substance with an atomic weight of 286. This value was unknown to the atomic table!

“The properties of this gas are different from anything yet known to science,” Tom told his older colleague.

After a further hour of work, Cully said, “Tom, permit me to withdraw any doubt I ever uttered or implied about the value of this expedition. This gas is basically a carbon-fluorine compound, but composed of isotopes never observed in a natural setting. And that new silicon isotope, the one you’ve named Silicoidium—a magnificent paradox!

“Though my field is geophysics, not chemistry, I know enough to say that what you have here is absolutely revolutionary in its implications.”

“But we still have to determine the exact sequence of its chain reaction,” Tom commented, modestly setting the superlatives aside. “These samples of gas are ‘spent’—barely sputtering with antiproton generation. The real deal is still down underneath Goaba, on the other side of that barrier of rock.”

They continued talking as they exited the physics cubicle. Noticing that it was nearing midnight, Tom decided it was time to bring everyone back on board for the night and lock-up the ship. He and Ry proceeded to the bottom deck and paused at the open hatchway.

“Odd,” commented Ry. “I don’t hear anyone. But they don’t seem to have entered the ship.”

Tom called out a couple of times and tried the intercom. There was no response.

“You don’t suppose they’ve taken ill from one of Chow’s concoctions—do you?” the Professor speculated nervously.

But a more frightful possibility had occurred to Tom. While they had been working obliviously aboard the Flying Lab, their ruthless enemies might have struck—and eliminated the rest of the expedition!















TOM AND RY frantically searched through the ship for their companions, then went out into the clearing.

“If we’ve been attacked as you suspect, they may still be out there waiting for us!” protested Ryerson Cully.

“I’ve just swept the area with a special kind of radar device,” Tom responded crisply. “It can analyze patterns of motion within a range of about half a mile, even among the trees. There’s no sign of any human-like movements. So, Professor, please focus on finding out what happened to our friends!”

“I’ll do my best,” he said. “I apologize for my nervousness.”

They walked throughout the stony clearing, the radius of which was about twice the length of the Sky Queen, looking for clues. It appeared that the residue of supper had been neatly cleared away.

“I think they were all just taking it easy before turning in for the night,” murmured Tom. “Look at the folds and indentations on the tarp—it looks like they were sitting in a circle. But then― ” Tom pointed to another spot. “It looks like people were dragged across the tarp and out into the clearing, like dead weights.”

“P-perhaps they were rendered unconscious in some manner,” said Ry softly. The more likely alternative was too terrible to mention.

Inside the ship Tom rushed to the control compartment to establish contact with Swift Enterprises, where it was midday.

“The possibilities are horrible, son, but you’ll only make the situation worse by speculating,” Mr. Swift advised his son soberly. “In fact, you simply don’t know what happened.”

“But I can’t just sit and wait!” Tom protested.

“No,” his father agreed. “Of course not. What is your plan of action?”

“For one thing, I’m going to lift off in the ship and search for miles around with the big searchlight and the motion-analyzing radarscope. If I haven’t found them by dawn, I’ll have to contact the authorities. But I won’t let them drive us away from here, Dad!”

“I can’t…” There was a crackle of static, and Mr. Swift’s voice resumed in midsentence. “… could be affecting your signal. Is it…” Again the voice faded out.

“Dad, it’s the anti-electronic effect I described. It’s that time. I’d better take off and search while the Queen is still operational—I don’t want to wait.” Tom switched off the transmitter. I hope Dad got the message, he thought.

Tom activated the flight controls. The dials were already beginning to waver. “At least I ought to be able to search in the direction away from the mountain,” he muttered. He fed power into the jet lifters, and the Flying Lab thundered somewhat woozily into the night sky.

The weary young inventor criss-crossed the local terrain from above for hours, illuminating small sections of it by the Swift Searchlight, as if by clear daylight. Once, near the Onari village, Tom thought he had detected a human movement pattern down in the brush, but closer examination by searchlight revealed only a magnificent lion hunting its prey under cover of darkness. Both the local settlements—of the Maba as well as the Onari—were quiet, with a few patrolling perimeter guards the only sign of life.

Tom also circled twice around Mount Goaba in the Sky Queen toward the end of his search, as the anti-electronic effect was beginning to dissipate. Again, there was no sign of life or motion.

His options having run out, Tom headed back toward the base camp clearing. He was relieved to see the terrasphere tank and its descent sphere lying unmolested in the brilliant moonlight.

“I know I should have packed them away,” Tom murmured to Ry, “but under the circumstances, I― ”

“No one could fault you, Tom,” said Professor Cully gently.

Suddenly both passengers jumped as the skyship’s radio beeped with an incoming message on an unfamiliar frequency.

“This is Tom Swift in the Sky Queen,” Tom responded cautiously. “Please identify yourself.”

The radio hissed, whined, and buzzed, but finally a quavering message could be faintly discerned. “We have your people here with us,” said a voice, heavily accented.

“Who are you?” Tom cried. “I demand to be allowed to speak with the other members of my party.”

The reply was lost in the crackle of static.

“Tell me where you are,” resumed Tom.

… village… you flew over… set free if you agree to… “ sputtered the radio speaker.

“This is quite useless!” snipped the Professor.

“Please repeat,” Tom said. “I can barely make you out. What is it you want?”

The answer was clear and immediate. “We say, you must come here, Tom Swift. We will release your people to you personally. They are unharmed, but in our control.”

What do you want me to do?”

Come alone to the Onari village, Hyaddongo. You must walk there from your camp. We do not wish your aircraft to approach. Arrive by noon tomorrow, without weapons. And we insist that you not contact others, or we will not cooperate and it will not go well for your people.”

All right, I’ll do as you have asked,” declared Tom. “To whom am I speaking?” But there was no reply to this, or to further questions.

Tom switched off the radio and sat as if dazed, staring off into the distance.

“You intend to comply?” asked Cully.

Tom nodded.

“They will surely make you a prisoner—and that is being optimistic.”

“I have no choice, Ry,” said Tom. “You’ll remain here with the Queen; and if you haven’t heard from me within 48 hours, contact my father.”

Dawn was breaking. Unable to snatch even an hour of sleep in his tense state, Tom showered and picked at a small breakfast, then left the skyship, directing Cully to seal the hatch behind him. Bearing a detailed map, he trudged off into the wilderness.

The trek through the jungle took most of the morning, but by ten minutes after eleven, he saw buildings and people ahead, and in a few minutes he stood at the perimeter of the Onari village. The villagers, obviously very poor and deprived, regarded him without emotion as a half-dozen Africans in military fatigues—worn and faded—swarmed over him searching for weapons or communications devices. Finally one soldier, who curtly introduced himself as Sergeant Uthabu, led him through the run-down settlement, stopping before a large wooden building, the only two-story building in Hyaddongo. Tom was ushered inside, into a sparsely furnished room—furnishings consisted of a single wheeled desk chair and a florid ornamental lamp that sat on the floor—where he was commanded to wait.

“Do not sit down!” said the soldier, who turned and left.

Bone-tired and full of fear, Tom waited, hands at his sides.

Tom!” came a voice from behind him, and he whirled about.

“Mandy!” Tom cried happily. “And Craig!” They came rushing into the room, none the worse for wear. Another figure, a massive one, followed behind them, pulling the door shut.

“I would say ‘we meet again, Tom Swift,’” said the man with forced joviality. “But the truth is, we have never met in the first place.”

“But I know who you are, General Boondah,” said Tom coldly as the man took a seat in the cushioned, rolling desk chair—which lacked only a desk.

“Already you are wrong,” said the big man. “I am to be addressed as His Excellency and Supreme Commander, President Osa Kotto Boondah. You see, I am President of this sovereign republic of Borukundi, and you must recognize that, lest you insult my countrymen with your colonialist attitude.”

Tom gazed at the grinning man stone-faced, then half-turned and spoke to Craig. “Are you all right?”

“They are all right,” said Boondah. “And you will speak to me alone, young Tom.”

“What do you want of me?” Tom asked.

Boondah was silent for a moment, staring at the youthful American. Then he gestured at the raft of gleaming medals and colorful ribbons that bedecked his broad chest. “What do you think? A nice display. And they are all quite genuine, my friend. This I know, for I conferred them on myself!” He laughed loudly. “I have decorated myself for many instances of courage, and for humanitarian work, and for making the lions quiver in their dens. No doubt you are impressed. Ah, but this little one here is my favorite. I truly earned this one.” He patted the medal proudly with his forefinger. “For tying knots as a Youth Scout.”

There was silence, and Tom asked if the other members of his party would be released as promised.

“Of course. Did I not say so?” He thought. “Ah me, perhaps I failed to say so; yet it is in my heart to do it.”

“Pardon me, sir,” said Tom calmly. “I fail to understand why you have had my expedition taken prisoner, or why I am here.”

“Your people were arrested by my Agrarian-Reform Policemen. You are in Borukundi without proper papers. Do you deny it?”

Tom noted that he had secured clearances from the country recognized by the United States as the owners of the region.

“And you see, that is just what I do not like about the United States,” said the Supreme Commander in response. “Nor do I care for Mount Rushmore, or fried foods in little paper sacks. Your people will not accord my people respect for their democratic choice to function as an independent state.”

“Democratic choice? You took power in a military coup!” grunted Craig Benson.

“No comments from the peanut-gallery, if you please,” said Boondah with a mocking smile. “As the saying goes, if I want your opinion I will beat it out of you.” He laughed heartily. He said to Tom, “You must realize, in Africa democracy is not by votes, but by consensus. The people who live in Borukundi, the Onari, are crazy about me! It would be undemocratic to refuse to lead them.”

“Are the Maba crazy about you also?” asked Tom.

“Bah!” cried Boondah with passionate contempt. “I will tell you a fact: they are offspring of a donkey and a snake. It is true. I read it in the biology textbook I wrote. ‘Maba’ means ‘I crawl on my belly and soil the earth.’ That is the definition.”

Tom smiled. “You wrote a dictionary too?”

The General laughed again. “I am enjoying my time with you. But manners, manners!—it is time for lunch. Do you care for cucumber sandwiches?”

“I’m not hungry.”

“Nor are they big enough to feed a hungry man. But I shall not eat in front of you—it is rude.”

“All right, sir,” said Tom with an edge to his voice. “Have you had enough entertainment? I would much like to know the purpose to all this.”

Gripping the arms of the office chair, the President leaned forward, his bulging eyes suddenly as fierce as a hawk’s. “You have been engaged in mining operations at the mountain erroneously called Goaba by the Maba traitors. Its true name is Yossaffo. I have named it after one of my descendants, who shall be born in about 70 years.”

“We have been to the mountain,” Tom conceded, “but only for purposes of scientific study, not mining.”

“So you say. Your very presence there is illegal, an interference in my agrarian-reform program.”

“Do you plan to put farms on the side of the mountain, Mr. President?”

“Surely not. That would be daffy, eh? But there is a principle of respect to be observed. Respect matters. I respect, you respect, we respect—that is what our children are taught. What are children taught in America, eh? How to program their VCRs?” The Supreme Commander did not seem to expect an answer.

“Then I take it you are ordering us out of the region.”

Boondah waved a hand dismissively. “Nonsense! Who said such a thing? I am only reminding you that you are probing the sovereign soil of Borukundi. Whatever you find there belongs to the people, the Onari.”

“Not the Maba?”

“They are not ‘people’.”

Tom nodded slowly. “All right, sir, you’ve made your point and I understand it. Our expedition will proceed with that in mind. We intend no disrespect.”

“Of course not,” said Boondah. “If I thought you had intended it, I would have taken a gun and shot you myself.” He stood. “And so this diplomacy is ended, and I am off to cucumber-land.”

“Then my friends are free to return with me to our camp?” asked Tom eagerly.

“They are awaiting you in front of this very building—all but one.” The General emphasized the ominous sound of his last remark with a frown.

Tom paled. “What do you mean?”

“One of your party shall remain here, as our guest. I don’t recall his name—you figure it out. He will be—well, I do hate to use the word ‘hostage.’ But that is what he is, eh? When your big beautiful ship has left this country, we will escort him to the border for you to pick up. It is an incentive, so you will continue to show respect and good behavior.” Tom began a bitter protest, but Boondah raised a warning finger. “No no, young Tom. Everyone loves a winner, but no one likes a whiner. That is one of our national slogans. I am most glad I wrote it!” He straightened his military-style jacket and swaggered out the door.

Sergeant Uthabu reentered and motioned for Tom, Craig, and Mandy to head outside. There, in the hot sun, stood Bud Barclay, Hank Sterling, Chow Winkler, and Dr. Simpson.

“Great gushin’ Rio Grande!” cheered Chow in hushed tones, with a nervous glance at Uthabu. “Are you ever a welcome sight!”

“How is everyone?” Tom asked.

“They snuck up on us!” hissed Bud. “We were singing after we finished our meal, and suddenly these guys came charging out of the brush slinging gas grenades.”

“We all blacked out,” continued Hank. “When we came to, we were in some kind of big dug-out in the jungle, camouflaged by branches. It couldn’t have been more than a mile from base camp—we heard the Queen take off pretty well, and now and then we saw the searchlight beam between the branches.”

“Arv Hanson is missing,” put in Doc Simpson. “He wasn’t in the dug-out, and he wasn’t in the building they drove us to earlier today. We don’t know what’s going on.”

“Hanson is being held as a hostage until we leave the country,” Tom explained grimly.

“Held by who?” Bud asked.

“We have just been in the august presence of the Supreme Commander,” said Mandelia with dripping sarcasm. “He is concerned about disrespectful mining operations at Goaba.”

Chow shook his head. “What in tarnation does that mean?”

“It means there’s something in or around the taboo mountain that General Boondah doesn’t want discovered,” said Tom Swift. “That’s my guess.”

Hank Sterling approached Tom and said in a low voice, “If it’s the antiproton matter, that’s not good news for the world.”

Tom nodded silently.

“Come!” commanded Uthabu. He herded the party to the edge of the village as other armed men looked on, ready for trouble.

Tom had hoped they would be driven back to camp in some manner, but hopes were dashed. Uthabu merely pointed and said, “Now go!”

The group trudged dejectedly through the jungle pathways, discussing their experiences.

“I don’t think it’s the antiproton stuff they’re after,” pronounced Craig. “Mandy knows the Onari lingo and listened to our guards talking.”

“They mentioned ‘ootna mu’achingi’,” she said, “which means—approximately, as we are in mixed company—little green acorns.”

“Don’t sound like that there gas,” Chow commented. “But mebbe it’s jewels, or nuggets.”

Tom did not respond. He was pondering the situation of Arv’s captivity, and wondering what to do next.

The trek back was much longer than Tom’s morning journey. It was baking hot even in the shade, and everyone had to sip frequently from Tom’s water canteen. But at last, as twilight was falling, they came in sight of the Flying Lab and the terrasphere paraphernalia.

“There’s Ry in the window,” Tom said, as he and the professor exchanged waves.

Suddenly Bud lay a hand on his pal’s arm.

“Tom!” he whispered. “Someone’s hiding out there!—I just caught a glimpse of movement in the brush.”

Before Tom could react to this warning, a dark silhouette rose into view!














“I CAN’T believe it!” Tom cried in amazement. “Arv!”

Hanson stumbled toward the warm greetings and round of back-slapping that awaited him. He was dirty, scratched, bruised, and bleeding, but for a moment didn’t seem to care.

Hanson said only a few words until they had all piled into the ship, and the doctor had applied antiseptic to his wounds. Then, in the lounge, he commenced his story.

“I was sitting around with the others when the men attacked,” Arv said in a hoarse voice. “Everybody seemed to keel over all at once—except me. I was unaffected. But I thought it best to pretend to be knocked out, and to observe what was going to happen.

“A dozen men in uniforms came swarming in and dragged us off into the jungle, where they piled us into these rickety wooden carts with big wheels, which they pulled along by hand. After a little while they stopped—I suppose it was at that dug-out you guys mentioned—and they all went forward to pull open the camouflaged door, or something. When their backs were turned I was able to squirm out of my cart and hike off into the jungle. Nobody followed me—though from what you say, Tom, they must have eventually realized that they were one body short.”

“I suppose they hoped you’d not make it back through the jungle, or that they’d eventually recapture you, so Boondah pretended to have you in custody,” Tom said.

“From a hiding spot some distance away, I saw them all go into the dug-out and pull the door shut. Then everything was quiet—just me and the trees and the lions! I had no idea of what direction the Queen was in. So finally I just rolled up under some fallen branches to wait out the night.”

“When you heard the ship flying around, you could have come out and waved your arms,” Tom pointed out. “The radar would have detected a human presence down below.”

“I know,” said Arv sheepishly. “But as a matter of fact I fell asleep—and I’m a mighty sound sleeper!”

“Snores like a sawmill,” Chow commented.

Arv concluded by saying, “I spent most of today just trying to get my bearings. Finally I caught sight of the camp.”

“But why were you not affected by those grenades, I wonder?” murmured Ry Cully.

“The explanation is obvious,” said Doc Simpson. “The gas must be based on the same flower extract that put Ry in a state the other evening.”

“Sure!” exclaimed Bud. “Arv is still immune.”

“From now on, Arv, you get lead position on our caravan,” Tom joked.

After making a report of the day’s dramatic events to his father by radio, Tom joined the others in a full night of welcome sleep.

The next day a team of explorers embarked for the mountain. In the passenger cabin of the terrasphere tank were Tom, Bud, Craig, Hanson, Chow, and Mandy Akwabo. Hank Sterling piloted the tank from the turret, and Ry Cully volunteered to travel inside the descent sphere, which had been lowered into its cradle on the mobile platform and locked in place. Only Doc Simpson remained behind on the Sky Queen.

Do you really expect to use the sphere itself this time around?” asked Mandy.

“Perhaps not,” Tom replied, “but there’s no harm in bringing it along. Eventually I’m sure we’ll need it to descend into the cave system.”

“You think the source of the gas is pretty far down?” Arv inquired.

“I have it figured out,” replied the young inventor, “though that doesn’t mean I’m right! I assume the ultimate source of the reaction is at sea level, because of the effect of the rising tide. Now in this area― ”

Mandy interrupted. “Please, allow me to show off my expertise. For miles around, this whole region of Borukundi is somewhat elevated, a slight rise or ‘dome,’ if you will. The land rises further, in steps, as we approach Goaba; and of course the base of the mountain provides further elevation. At the taboo mountain we are really on a very shallow extension of the Massif du Chaillu, a volcanic feature of this continent, which plunges down into the Congo basin as one travels eastward.”

“This is jest like bein’ in school,” said Chow, fascinated. “Except I’m awake!”

“At any rate, I have estimated the distance down from the crevice to sea level to be about 2000 feet,” concluded the geographer.

2000!” Bud exclaimed in surprise. “Tom, the cables aren’t nearly long enough!”

Tom chuckled. “Don’t worry, flyboy. We’re not lowering the sphere from the crevice, but from the end of that cave, which is already many hundreds of feet below the surface.”

With a promise from Tom that they would all be able to take a turn in the descent sphere before the Sky Queen departed for Shopton, Chow and Craig had agreed to serve as guards while Tom and the others ventured into the cave.

“Remember,” Tom instructed, as they reached the entrance—now a broad fissure with sides like a bowl—and the two men stood up to get out, “keep your radiation-proof suits on at all times. And if we’re not back in four hours, get away from here. We may have drilled through the wall by that time. According to my tide table, the gas should appear about then. Despite the Inertite coating on your suits, this place won’t be fit for man or beast.”

“But what about you?” Craig asked soberly. “You’ll be much closer to the source.”

“I don’t expect anything to happen, of course,” Tom replied. “But if we are delayed, we have our own antirad gear, and the terrasphere tank with its fresh coat of Inertite will provide double protection.”

Wishing the explorers luck, Chow and Craig climbed down to the ground and Ry joined the rest in the passenger cabin. Those outside waved goodbye and Tom, trading places with Hank Sterling, drove the terrasphere into the cave. He switched on the spotlight and the vehicle moved ahead slowly.

The tank had gone only a hundred feet when Bud made a discovery. “Look! On the left-hand wall! Someone’s been digging in the rock since we were here!” He immediately intercommed the control dome.

Tom stopped. Bud and Hank climbed out and searched the spot. The evidence was unmistakable. Large chunks of rock had been dug from the wall. The two young men stepped back into the cabin and informed Tom of their findings.

“We have to be on extra alert if there are others in this cave,” Tom said. He threw the tank into gear, and Terry resumed her rumbling downward journey. But they had proceeded onward less than a minute when a huge shock nearly swept the vehicle onto its side!

Dynamite,” intercommed Tom when the supergyros had steadied the platform and the echoes had faded away. “I’m sure of it!”

“Hoplin and pals have boobytrapped the cave!” Bud cried heatedly. “They must be planning a cave-in to stop us!”

“Why that’s murder!” gasped Ry.

“They don’t realize a few things, though,” said Tom over the speaker. “First, we’ve found that the antiproton effect has somehow made the molecular structure of the rock extremely rigid—a phenomenon I’d like to study. It won’t be easy for a few dynamite sticks to set off a cave-in. Second, Terry is built to withstand bad shocks.”

“And third, they haven’t reckoned with Swift stubbornness!” chortled Bud.

There were no further explosions, and presently the tank arrived at the terminus of the glowing cave, the rock wall that had stopped them before. The crew unstrapped and unloaded the refurbished earth blaster, positioning it to bore into the barrier. Then, backing several score feet up the tunnel, Tom sent the signal to activate the machine. This time, the earth blaster functioned without interference!

“Your new coating technique is quite a success, Tom,” congratulated Hank.

An hour passed with all the team watching the monitoring instruments. All were working perfectly.

Stopping the machine periodically, Tom carefully examined the soil and each type of mineral as it spewed back from the drill-head, discussing it with Ry Cully. Eventually the blaster unearthed a layer of white, glazed rock. According to the instruments, the original cave at this point narrowed to only a fraction of an inch in width.

Intrigued by the sudden change in rock formation, Tom drilled more rapidly. The glazed layer proved to be only two feet thick. “But it’s taking forever to drill through,” Tom pronounced over his radsuit communicator, as he stood outside the tank with the others. “The hardness effect is especially strong here.”

“You must be very near your goal,” commented Mandy.

Seconds later the cables trailing behind the blaster jerked forward in a series of staccato moves. “We’ve broken through!” he called out happily.

But then as the blaster bored ahead, an overpowering force suddenly gripped it. The cables, control housing, and instruments were yanked forward into the narrow hole made by the machine. Every instrument was smashed against the rocks and shattered.

With a shout of alarm Tom rushed forward and began pulling on the cables, helped by the others. The cables came up far too easily—finally revealing ends that were broken off and hanging empty.

“The earth blaster is gone!” Tom cried. Then, as a panicky thought struck him, he bellowed, “Everyone—run for your lives!”














THE EXPEDITIONERS turned as one and raced for the shelter of the tank. Once inside, they gazed toward the opening in the rock barrier that the earth blaster had made. The inside of the tubelike passage reflected a flickering reddish-gold light.

“Guess my fears were unfounded,” said Tom a little sheepishly after checking some detector instruments. “I thought I might have released a pocket of the gas powerful enough to disintegrate the blaster.”

Nevertheless, the crew waited for half an hour before venturing outside again. As they waited, Bud asked Tom what he thought had happened.

“I believe the earth blaster was sucked through past that layer of glazed rock,” the young inventor replied.

“Sucked into the ground?” Mandelia asked in astonishment. “But how could that happen?”

“There’s only one logical explanation,” said Tom. “I must have bored into a large semi-vacuum area. The crevice tunnel probably opens into a great underground pit, with the tidal river at the bottom which sucks out the air. When we broke through the wall, the outside air rushed through the opening and the earth blaster went with it.” He added that the abrupt stresses on the flex-points of the cables and feed tubes had probably cracked the Inertite layer, exposing the material underneath to disintegration from residual antiprotons.

“If there is such a central chamber,” said Hank, “do you figure it adjoins the cave?”

“Yes,” Tom replied. “Tomorrow we’ll go all the way to the end of this cave with the terrasphere tank. If we do find a pit beyond that barrier, I want to take a ride down into it in the sphere.” But first, he added, they had hours of work before them as they labored to enlarge the opening made by the earth blaster.

“With the blaster gone, I don’t see how it can be done,” said Arv, discouraged. “Especially with that white glaze being as hard as it seems to be.”

“Actually, it may not be as difficult as you think,” said Tom mysteriously. “Nature may give us a hand.”

They worked for another hour with picks and shovels and handheld drilling equipment. But as they piled back into the tank, Tom admitted that they had made scant progress.

“I’ve left an Inertite-coated sensor in the opening, which will send us a signal when the gas appears,” Tom noted.

The tank was turned about and Terry made her way back up the great underground ramp to the surface. As they finally emerged into the open, the explorers were surprised to find that a dark gray sky awaited them.

“A storm coming in,” said Mandy with concern in her voice. “They can be quite fierce.”

“I’m more concerned about our guards,” Tom said. There was no sign of Chow or Craig at the entrance.

A panic seized Tom and the others. There was no reason for the men to have left there posts, unless there had been foul play!

Tom switched on Terry’s external loudspeaker and called out Chow’s and Craig’s names. Detecting no response, Tom cautiously made a half-turn in the tank, gazing about among the rocks.

“Hoplin must have managed to surprise them,” Bud declared tensely. “That, or― ”

“Or what?” asked Professor Cully.

“Let’s just say it might have been an inside job,” Bud finished.

Tom frowned at Bud, but did not comment. The two climbed out into the mottled sunlight.

Immediately they were assailed by shouts from two different directions. For a fleeting second the travelers tensed for a raid. Then smiles of relief spread over their faces. From behind a massive rock on the slope above emerged the plump figure of Chow in his antirad suit, and Craig came out from behind an outcropping down below them.

“You had us worried!” Tom cried out. “Thought you’d been kidnapped!”

“Naw, boss,” said Chow. “Jest a little bit o’ strategy.” He and Benson explained that not long after the tank had entered the tunnel, the enemy plane had flown low over them, circling twice before moving on northward.

“When we first heard the buzz of the engine, we got out of sight,” Craig explained. “Even after the plane left, we figured staying in hiding might be a good idea.”

Tom then described the underground boobytrap and the loss of the earth blaster.

“Genius boy here thinks we won’t need it after all,” said Bud skeptically. “Guess the trolls and gnomes are going to finish the dig for us.”

“Are trolls and gnomes native to this part of the world?” asked Arv jokingly.

“Africa has everything!” Mandy answered.

The team all returned to the comfort of the terrasphere tank. They drove a quarter-mile away into the brush, then pitched camp for the night, inflating a pair of balloon-like plastic tents to sleep in. Working inside Terry’s passenger cabin Tom jotted down notes and made a list of figures. Only when the last streaks of a blood-red sunset had faded from the angry, overcast sky did he interrupt his work. The young inventor lay down on the cushions in the cabin and fell asleep almost instantly, to the sound of the restless wind.

A loud buzzing awoke Tom. “What is it?” he murmured, then suddenly snapped awake. The alarm from the gas detector in the cave!

He checked his wristwatch. Right on schedule, he said to himself.

When the group breakfasted in the morning they found the gray sky growing formidably dark. Strong winds began to raise huge whirlpools of dust across the open spaces, and the boughs of the taller trees began to claw one another like animals.

Menacing black clouds boiled overhead in the savage churning of the turbulent air. Drops of rain spattered against the tents.

“Maybe we ought to get out of this area completely!” Bud suggested. “No telling what may happen when rain gets into that crevice.”

Agreeing, Tom drove the tank a good distance from the mountain but felt it best not to travel among the trees in the tropical storm. Within seconds, visibility outside the cabin was reduced to zero as a drapery of torrential rain descended. The wind exceeded gale force.

“Look at that lightning!” Bud cried out.

Suddenly, like a sinking ship, the vehicle began to list heavily to one side.

“Good freakin’ grief!” Craig cried. “We’re going to turn over!”

The occupants clung to their seats. The angle of the tilt became increasingly great.

“There must be a soft spot under our right tread-rings,” said Tom.

“Start up this contraption!” Bud demanded. “Let’s pull out of here!”

“Trying to move her now,” declared Tom, “might mire us deeper.”

The words were hardly out of his mouth when the entire vehicle shuddered and the cabin glowed lividly with an eerie light.

“We’ve been struck!” yelled Bud. “We’re on fire!”

In a moment Bud’s fears were allayed. Though the bolt of lightning had struck very close to the terrasphere, the vehicle was not on fire. A nearby tree, however, had been seared from top to bottom.

“Whew!” Bud exclaimed. “I don’t want any more of those!”

Tom gave his friend a quizzical look. “Have you forgotten, chum, that this bus is impervious to fire—even lightning?”

Bud looked sheepish. “I sure had.”

Despite the soft spot, the tank was slowly leveling itself again, and presently Tom was able to use the tread-rings safely.

“Ah, bless those gyro-supes of yours, Tom!” breathed Mandy Akwabo.

“What does Greek soup have t’ do with anything?” demanded Chow.

“I believe our colleague is referring to the tank’s supergyros,” Ry corrected the westerner. “Say, I wonder what the lightning and wind are doing to the tunnel opening?”

The young scientist wondered too. He hoped any accumulating or streaming rainwater would be absorbed or dispersed before reaching the subterranean pit.

To the relief of the occupants of the terrasphere tank, the storm showed signs of subsiding. The wind dwindled in velocity and the rain frittered away into scattered droplets. Suddenly the black thunderheads seemed to open up like a door, admitting slanting rays of yellow sunlight.

“Beautiful!” exclaimed Tom.

Craig commented wryly, “So’s a leopard, Sci-Fi—and these sudden storms can be just as deadly.”

After contacting the Sky Queen by radio and verifying with Doc Simpson that the storm had done no damage in that area, Tom returned to the great opening in the mountainside and prepared to reenter the earth.

This time Hank Sterling and Bud were left behind to keep watch, and Chow and Craig were included in the tank cabin.

“Brand my lightnin’ bugs, this place is lit up like Abilene on the fourth o’ July!” remarked Chow as he gazed out the cabin window at the passing tunnel wall.

“I believe the excess moisture in the air has increased the phosphorescence of the rock,” was the Professor’s explanation.

As they arrived at their former stopping place and disembarked, Mandy commented to Tom, “Now we shall see how well the trolls and gnomes did their work.”

“Take a look,” Tom urged.

The group approached the point where the rock wall had stopped them before.

“What in the world happened here?” boggled Arv Hanson.

The rock barrier had vanished! The tunnel was now yawning wide before them!

Ah, yes, I see,” said Ry Cully with a glance at Tom. “Your hypothesis was correct.”

“Explain it, boss!” Chow demanded.

“No black magic involved this time,” replied Tom with a broad grin of triumph. “You see, the entire ‘plug’ filling the corridor was fresh rock that had fallen from the ceiling, and most of it had never been exposed to the antiproton gas. Unlike the rock in the walls, which is laced with Inertite—the gas disintegrated the unprotected parts aeons ago—the new rock was still vulnerable. The rush of gas through the hole made by the blaster was enough to dissolve it away.” He pointed to the floor of the new passageway. “See that layer of powder? Inertite that was left behind.”

Inner tight?” sputtered the Chow. “Oh, you mean that new paint you cooked up!”

“Yes, pard. It’s like Tomasite. The only difference is that Inertite is immune to antiprotons, whereas Tomasite is inert to gamma rays and alpha and beta particles.”

Chow, completely bewildered by Tom’s explanation, scratched his head. “Don’t you bother runnin’ through the alphabet, Tom. I don’t savvy nothin’ ’bout them rays an’ things!” he snorted. “I’d ruther take my chances ridin’ one o’ them convict cow ponies.”

“Convict cow ponies?” Tom asked. It was his turn to be puzzled.

“Sure!” Chow answered. “Them poor black an’ white critters with all the fancy stripes!”

“Oh, you mean a zebra!” Tom grinned and gave Chow an affectionate look.

“That antiproton gas is pretty dangerous!” commented Hanson, regarding the tunnel in awe. “Will it ever have any practical uses?”

“It’s only a matter of learning how to harness the gas,” Tom declared. “Already I see the possibility of using it to form completely new isotopes. In fact, with it, I’ll be able to imitate the isotopes found in the rocket from space—the capsule we recovered from the Atlantic.”

“Brand my pot covers!” cried out Chow. “What you talkin’ about—icy topes from Mars?”

The others laughed and Tom informed the Texan that he had already made some amazing discoveries about the gas. “It’s out of this world,” he said with a wink at the others.

“What are you going to call this new gas?” Craig asked.

“Exploron,” Tom replied.

Dressed in their antiradiation suits, the crew now hiked through the newly-open corridor, noting any spots that might be a tight squeeze for Terry. In a minute they had reached the far end, where the walls of the corridor funneled together, leaving only an opening the diameter of the lost earth blaster.

“This is it!” Tom announced. He tossed some of the white powder into the air, and it was immediately whisked through the opening.

“Can you widen the hole enough for Terry to get through?” asked Craig.

Tom shook his head. “She doesn’t have to—just her nose.” He explained that he would widen the opening just enough for the crane boom and descent sphere to be able to pass through. “We’ll lower the cabin from there, while the tank section stays on this side.”

As expected, this last layer of rock proved the toughest of all, requiring the use of special diamond-tipped tools from the tool locker. But after much slow and strenuous work, there was a sudden loud sound and several broad sections of rock suddenly cracked and tumbled forward out of sight with a whoosh of wind. “This time I’m glad to eat my words,” said Tom, puzzled. “Looks like there’ll be plenty of room for the whole platform to enter after all!”

“A gift of Mother Nature!” said Mandy. She stepped closer to the opening, the edges of which were alive with trembling colors reflected from somewhere ahead and below. Suddenly she cried out in alarm as a segment of the floor, broad as a doorstep, suddenly cracked and tilted forward.

“Just back up slowly,” directed Tom. “Don’t make any sudden moves. We’ll toss you a rope.”

Suddenly Mandy shrieked as the fragment beneath her feet broke loose completely and slid toward the opening! In an instant she had pitched over the edge and into empty space!

“No!” cried Ry Cully.

But then a weak and wavering voice came to their ears by way of the inter-suit communicators. “I’m—I’m okay!” gasped Mandy. “I just slid a few yards down a slope, onto a ledge. But I don’t think I can climb up! And I’m not directly below—I slid at an angle, and I’m a dozen feet off to your left.”

“We’ll lower a rope to you,” said Tom. “We can put a weight on it and swing it to the side.” But the project proved more difficult than expected. Putting any weight on the cable caused it to gouge into the lip of the opening, which in turn caused more rock to crack and crumble away; nor could anyone stand at the edge to guide it.

“You’ll have to drive the tank into the passage, then lower one of the cables from the crane arm!” Cully urged in frantic tones.

“We have to test the strength and composition of the rock,” Tom replied, an expression of anguish in his eyes. “Otherwise the weight might cause the whole floor to shatter and collapse into the pit.”

A change seemed to pass over Ry Cully’s face. Fear and dread were replaced by resolve. “Young man, this is absurd! Unreel one of the crane cables and hand me the end. I shall pass it through these loops on my suit and lower myself down to the ledge.”

“Professor, I can’t allow― ”

Cully cut him off. “There is no use arguing—I am quite intent! I weigh a good deal less than any of you other gentlemen, and I am the most logical choice for this task. Now snap to it!”

Tom complied, and in less than a minute Ry Cully was lowering himself down the steep slope on the other side of the opening. Though the edge of rock above him was crumbling under his weight, he was able to nimbly step aside as pillow-sized boulders came bouncing down the slope. Pushing with his legs he swung his way over to Mandy and tied the free end of the cable to her suit; now both of them were strongly tethered.

“But what will you do now, Ryerson?” she asked. “If we put our combined weights on the cable, it will pull down the whole― ”

“You will have to move in a very athletic manner, madam,” said Cully. “You appear fit enough. And our ascent will be brief.” He radioed Tom to back the tank away from the opening as rapidly as possible. Tom started the engines, then, giving Ry and Mandy a warning, threw Terry into reverse.

As the long cable yanked the two upward violently, they bounced twice against the slope, then cried out in pain as they were dragged over the edge of the opening, which was falling apart under the bite of the sliding cable. When Tom screeched Terry to a halt the two were a good twenty feet up the corridor away from the chasm—yet the floor had cracked and tumbled away almost to that very point.

“You are as brave as a warrior, Ry,” breathed Mandy.

Ry seemed to like receiving the praise as much as Mandy liked giving it. “Why yes, I suppose so. And now I believe I’m going to—to faint!” He sat down but managed to retain consciousness.

Having ascertained that neither Mandy nor Ry had suffered any serious injury in their ordeal, Tom turned his attention to the walls and floor of the cave-end, trying to determine how far it would support the weight of the tank and sphere combination. He took a variety of samples and readings, proceeding methodically for more than two hours and studying the results in the passenger compartment.

“What’s the verdict?” asked Arv. “Did something counteract the hardening effect?”

“At the very end of the tunnel, the floor extends out onto a sort of overhang that is riddled with tiny holes—it looks like coral, in fact. The white Inertite-rich rock is just a thin crust over it, though it’s much thicker on the sides and above. With the gyros to stabilize the platform, we should be able to drive to within about eight feet of the edge without difficulty.” He glanced at his wristwatch. “We’re within two hours of the next eruption, and I’d rather avoid that risk. Let’s go topside and return in the afternoon.”

When they exited the mountain, Bud and Hank reported that all had been relatively quiet. “Not a creature was stirring, not even a wild boar,” Bud quipped.

The expedition drove several miles away from the mountain, then lunched in the open without the antirad suits.

“Whoa, look’t that!” exclaimed Chow suddenly. A large zebra had stepped out of the bushes about twenty yards away.

“One of your convict cow ponies,” said Craig.

“Wa-al, let’s jest see if’n he’s the friendly sort,” said Chow with determination. He approached the beast, which backed away skittishly and then slowly approached again. Suddenly, to the surprise of his audience, Chow produced a length of stout cord from inside his suit pack.

“What’s he doing?” asked Arv.

“Don’t tell me he’s going to― ” Tom murmured.

But he was! Chow made a loop and swung it like a lariat. In a moment he had lassoed the zebra by its vividly striped neck, and the animal was bucking violently in an attempt to escape.

“Charles, what you are doing is dangerous!” cried Mandelia. But if Chow heard the warning he ignored it. In another astonishing moment he had bounded up to the creature and thrown one plump leg over its drooping back.

Yee-hah!” cried Chow, waving an arm like a bronco buster.

“He’s nuts!” cried Bud. But the old cowpoke made such a droll sight on top of the struggling zebra—which was a few sizes smaller than a rodeo horse—that the watchers couldn’t help laughing and applauding as Chow was carried, violently jiggling, back and forth, in and out of the jungle.

“When you’ve had enough fun,” Tom shouted, “we’ll get back to science!”

Oh—I—I had me more’n enough fun—boss,” Chow yelled in response. “B-but this dang thing don’t s-seem to want t’ let me off!” But finally he was able to make it back to the ground, though at some injury to both his dignity and his posterior anatomy. After working the rope noose off the zebra, Chow let the animal gallop way. It was obviously glad to be free of the antics of Chow’s peculiar species.

As the period of the latest eruption had passed by that time, the expedition returned to the mouth of the cave in the terrasphere tank.

“Now the real expedition begins,” Tom declared. He paused, gazing off toward the broad, shadowed opening in the mountainside. “I’m taking the terrasphere right into the heart of the caves of nuclear fire!”












“TOM, is there room in that thing for two?” asked Bud quietly with a nod toward the descent sphere.

“Not for two Chow Winklers,” Tom replied with a grin. “But for you or I—sure.”

“Then let me go with you,” Bud said simply. And Tom agreed.

“I was going to ask you anyway, pal,” Tom remarked. He added jokingly: “It just wouldn’t be a trip down into an antimatter volcano without you!”

This time Arvid Hanson and Mandelia Akwabo remained at the entrance to serve as guards. With the descent sphere snug in its cradle, the tank platform again rumbled down the luminous tunnel with Bud at the controls.

“More signs of digging,” Tom noted. “They must have someone playing lookout at the opening. When they see or hear Terry in the distance, the signal is given and they run off to some prepared hiding place.”

“A terrible idea just came to me,” said Hank. “The members of this gang may not fully understand the implications of the antiproton phenomenon, even with that report they stole from your safe. If they haven’t been wearing sufficient protective gear, Nature will mete out a horrible fate to all of them!”

“I don’t want to feel sorry for these jokers,” muttered Craig; “but radiation poisoning is a pretty lousy way to die!”

“I’ll leave a written warning at the mouth of the cave when we leave,” Tom resolved. “But I doubt they’ll take it seriously.”

At the end of the main tunnel, just before the narrower section that the gases had hollowed out, Bud stopped the tank and the radsuited explorers got out to stretch. Tom had Bud raise the descent sphere a few feet out of its cradle so he could give it a final lookover.

“What is that fastened to the underside?” asked Ry, indicating a flat thick disk with several cuplike hollows in it that was fastened securely to the very bottom of the detachable cabin.

“Inside that instrument package are a number of narrow tubes that can be extended out through those openings,” explained Tom. “At the end of each one is a small scoop, along with a stiff wire that can vibrate at a hypersonic rate, just like the earth blaster’s penetrator vanes.” He described how the mechanism would allow him to obtain pulverized rock specimens from the walls of the cave as the sphere was lowered. The fine dust would be suctioned up through the tubes into accumulation canisters.

“Excellent!” pronounced the professor. “As a geophysicist I’m most anxious to begin analyzing the bizarre properties of this place. One might say that I am quite beside myself with scientific anticipation.”

Chow sidled up to Tom, speaking low. “Say, boss?”


“That perfesser feller seems right nice. But he sure does talk funny!”

Tom smiled. “You know, you’re right!”

The crew now reentered the vehicle. Tom skillfully maneuvered it through the opening and halted close to the gouged-out edge. At once another large section of the floor cracked and fell away under the forward tread-rings. But the supergyros did their job and kept the long platform level and steady, throwing most of its weight toward the rear, which was on a strong surface.

The group held a brief consultation. Then Sterling assumed his appointed post in the control turret. Cully, Chow, and Craig—Bud had nicknamed them the three C’s—would monitor the progress of the descent by means of a television feed from sets of Inertite-shielded cameras mounted on both the tip of the crane boom and the sphere itself.

“It’s a lucky break that the coating you were able to formulate is transparent,” remarked Craig.

“I’ll say,” Tom responded. “Otherwise we would have had to do this without windows.” He explained that the strange “nonmatter” structure of Inertite formed a sort of hyper-fine mesh of subatomic dimensions that allowed photons of light to pass through unimpeded while blocking the massive, destructive antiprotons.

Hank lowered the descent cabin to the flat top of the mobile platform, and Tom and Bud climbed a set of rungs on the side and eased themselves inside through the narrow hatchway in the top of the sphere.

“Man, this is going to be a tight fit!” exclaimed Bud. “Looks like we’ll have to lean against the walls all the way down.”

Tom chuckled but said soberly, “There’s still time to bail out, Bud. Once we get going, we’ll really be at nature’s mercy. No one knows what is going to happen down there!”

“I know, Tom,” said Bud, looking his best friend square in the eye. Then he broke into a grin. “Who will keep you out of trouble if I don’t go?” Bud jested, trying to hide the fact that he felt far from calm.

Tom seated himself behind an array of levers and switches. Temporarily taking control of the platform’s winch motors from Hank, he raised the sphere off the platform. Then he set the crane in motion. As the boom telescoped out foot after foot the cabin rocked gently. In seconds it had cleared the front of the platform.

“Ready, Hank,” Tom intercommed. “Control back to you.”

“Roger,” came the word from the control turret. Continuing to slowly extend the crane boom, Hank swiveled it slightly to center it in the shaft, and the descent cabin swung gently out over the mysterious pit.

“Ohh!” gasped Bud. “What a sight!”

And indeed it was, a sight like nothing else on the face of the earth—or beneath it; a sight no mortal man had ever seen.

The terrasphere was suspended over a great, round chasm, perhaps a hundred feet broad and many times that in depth. Great fingers of dark stone, like icicles in reverse, thrust upward from the sloping sides and bottom. At intervals up and down the walls of the pit were broad, ragged gashes—the ends of other caves that wormed their ways to unknown destinations in the earth’s crust.

The whole pit was alive with light. The walls were phosphorescent with a luminance like that in the cave from the surface, but here and there could be seen jets of red-gold flame seemingly fed by escaping gases—eternal torches memorializing in advance any who were foolish enough to enter. Like the bleachers at an athletic event, the walls flickered constantly with small, intense flashes, which Tom explained were caused by the collision of residual Exploron particles in the air with grains of stone not protected by Inertite.

But the most fantastic sight was hidden from view until the boys craned their necks next to the curving windows and gazed down straight beneath them.

“There it is, Bud!” Tom breathed. “Nuclear fire!”

The pit narrowed toward the bottom, then abruptly broadened into a wider gallery that opened on opposite sides into an underground channel. The gallery was half-full of rushing, churning, boiling water—a subterranean river that Tom and Bud knew reached all the way to the far-off ocean. The roiling waters were covered by a sheet of eerie fire, flames that were greenish-white near the water’s surface, lightening to tones of molten gold at their tips. Above the fire, an endless lightning storm raged, jagged blue-white bolts stabbing out at the rock walls without pause, bathing the scene in a harsh, throbbing radiance that hurt the eye.

“It’s like some kind of dream!” murmured Tom. “The surface of the river is acting like a liquid matter-antimatter reactor, constantly building up and discharging excess energy!”

Awestruck, Bud asked what happened at high tide.

“You can see that the rocks just above the water line are of a different color from the rest,” Tom responded. “The water, or something in it—perhaps even the salt content—produces a nuclear reaction in those rocks, releasing Exploron into the air.”

“Do you think all this just started fairly recently, Tom?” Bud inquired, rubbing his dazzled eyes. “I mean, why hasn’t the fuel been used up by now?”

Tom gazed thoughtfully at his friend. “The energy released from the collision of just one antiproton with just one nucleus of ordinary material is immense. If it weren’t for the Inertite, which must be generated as a byproduct of the basic reaction, the energy would be released all at once, in a blast that would crack the planet in two.” He turned to look down again. “This process has been going on since Day One on Earth!”

Tom now directed Hank to begin to slowly pay out the cables. Tom Swift’s descent into the fiery underworld had begun!

As the cabin slowly traveled downward, the adventurers gazed in awe at the unscalable walls of the phosphorescent pit. What beauty of color! The lower they went, the brighter the weird combination of radiant hues became.

“It’s magnificent!” Professor Cully exclaimed over the intercom from the passenger cabin above.

“Brand my radioactive peacocks, an’ thet’s jest on the TV!” added Chow.

Presently Tom checked his depth indicator. “We’re about three hundred feet down.’’

“How deep are we going?” Bud asked.

“I want to stop approximately one hundred feet above the bottom and try to retrieve samples of the reactive rock,” Tom replied.

Several minutes later he had Hank check their descent and peered at the flowing river below. It raged and crackled with the brilliance of a fierce fire.

“Sci-Fi, I’d never guess anything like this existed in the world,” commed Craig from above. “Utterly fantastic.”

“Nothing would stand a chance in that racing water, though,” Bud remarked to Tom. “See where it disappears under the mountain—not even headroom!”

“Guess it’ll be quite a while before we see tourists going whitewater-rafting on that river!” muttered Tom. Tom now worked his way sideways around the cabin, then put his hands on a special control panel Bud had not noticed before.

“Your rock-scooper control?”

Tom nodded and activated the tube-extender mechanism. After a moment a tube, thick as a garden hose, became visible through the window, stretching out bit by bit from beneath the capsule. It approached to within about two feet of the side of the pit—and then the boys shouted in surprise as a blinding flare of blue-white light burst forth from the rock and enveloped the tube’s scoop-end and hypersonic vane.

“I should have guessed,” Tom groaned softly. “Even though we’re not grounded, the metal tubes have too much current capacity. They de-stabilize the field balance near the wall when they come too close, provoking a discharge.”

Bud gulped, gazing at the end of the tube—now just a smoking knot of melted metal. “Tom, if Terry had gotten that close to the side― ”

“Right, pal,” Tom said, his face white. “That could have been us!”

Tom had Sterling draw the sphere upward in twenty-foot increments, trying the other tubes one by one. There were two more meltdowns. Finally, though, there was only a shower of sparks that seemed not to affect the scoop. Tom fed power into the hypersonic pulverizer, and in a moment reported that he had acquired his first sample of the mysterious Exploron-generating rock.

In the process, a stone about the size of a baseball had become dislodged from the wall. Bud watched as it dropped down to the river and plopped in at one edge, splashing a bit of water up on the bank. “Tom, look at that!” Bud cried. A plume of greenish, luminous vapor rose from the splash-mark. “It’s the gas!” yelled Bud excitedly and fearfully. “The glowing gas!”

Elated, Tom descended lower into the pit, hovering less than forty feet above the river.

“I’m going to obtain some samples of that gas!” he told Bud excitedly. “It may have a different composition from the Exploron we trapped before.”

The young scientist had just sucked a sample of the gas through the extended tube when the spherical cabin echoed with a loud, sharp sound, and tilted abruptly. The occupants almost lost their footing, and several lights on the monitoring panel turned an angry red—the color of trouble.

“Bud,” commanded Tom, “look through the pane in the overhead hatch and check the cables! This much Exploron in the air may be too much for the Inertite coating to handle!”

Bud scrambled up the small ladder and peered outside. “Good night!” he choked. “One of the cables is broken where it joins the sphere! Another is giving way!”

Frantically Tom clicked on the microphone which connected the cabin with the vehicle above. “Hank!” he shouted. “We’ve lost a cable! Start reeling us in!”

Hank acknowledged and the terrasphere started to rise. They were more than halfway back to the corridor opening when, without warning, the ascent ceased.

“Hank?” Tom intercommed. “What’s wrong? We need to go up to the top!” Almost immediately the descent cabin began to move again. But it did not move upward.

“We’re going down!” Bud cried.

Sterling!” Tom shouted into the mike.

There was no response!

He switched com channels in order to raise the passenger compartment. “Can anybody hear me?” Tom cried. “Acknowledge!” There was a burst of static, and Tom suddenly said, “The reaction that released the gas—it’s the anti-electronic effect.”

“But why is Hank lowering the sphere?” demanded Bud. “Could it be an electronic malfunction?”

Tom! Bud!” crackled a voice from the speaker.

“We hear you, Professor,” Tom responded. “We have to be brought up, but Hank isn’t― ”

“We’ve just been attacked!” interrupted Cully. “Men with rifles stormed the platform, broke through the dome on the turret—I can see Sterling lying outside on the ground in his radsuit. He’s not moving!”

Cully was abruptly cut off as a new voice broke through. “Swift, you’re ten times more trouble than you’re worth! Man, I wish that car had laid you out flat!”

Hoplin?” Tom demanded.

Pleased to meet you. Now drop dead!”

What are you― 

Save it, kid—I don’t have time to talk. The next voice you hear’ll be your own!”

The man growled out a laugh, then broke the connection.

“What’s he going to do to us?” asked Bud with terror in his eyes.

As if in answer, the terrasphere suddenly accelerated downward.

“He’s put the winch on maximum speed!” Tom cried. “He plans to drop us into the water!”

“Can the sphere survive?”

“The sphere?” Tom responded wide-eyed. “Bud, the splash we’ll make will blow the top off the whole mountain!”













AS THE DEADLY descent accelerated, the cabin tilted a bit more. The explorers looked at one another in sheer silent terror. A second cable had parted!

“We won’t have to wait for the cables to lower us,” whispered Bud. “Can’t you, somehow—take back the controls?”

Tom flicked a series of switches back and forth helplessly. “The controls on the turret override the ones here in the cabin,” he said. His brain worked feverishly. Suddenly he exclaimed: “Bud! We’ve got to eject the instrument package!”

Huh?” boggled Bud Barclay. “How will that help? The splash will just make more of the gas!”

Not taking a moment to answer, Tom swung over to the control panel that connected to the round module beneath the sphere. He flipped several switches, initiating a countdown. At the end, all the lights on the board flashed red, and the sphere resounded with a loud bang!

“Explosive coupler bolts,” Tom muttered to Bud. “For emergencies!”

“I suppose this counts as an emergency!” gasped the young flier.

The disk-shaped module fell to the river of fire and lightning, now close below. It plunged in, creating a broad splash that flung itself upon the nearby rocks, which instantly erupted into a sizzling shower of sparks. The entire pit echoed and reechoed with an explosive roar.

The terrasphere shuddered violently, bobbing like a cork caught in a powerful surf. The boys were thrown about bruisingly. As the shock abated, Bud glanced down through the viewport. “The gas—a thick cloud!” The highest wisps were only yards beneath the sphere! “Skipper, if that little puff of gas was enough to eat two cables, this will—!”

But Tom was already at work, fingers darting over the descent control board. Suddenly the sphere halted its descent. It hung lifelessly for a moment just above the cloud of gas, rocking slightly from side to side—and then began to rise!

Bud cheered. “How did you do that?—but please don’t stop while you’re telling me!”

Tom was in no mood to joke. “The anti-electronic effect. Dropping the module set off a strong pulse that threw the turret system above into reset mode—a window of opportunity to acquire control.”

The cabin listed at a sickening angle. A third cable had broken under the shock of the gas eruption.

“How few will hold up the sphere?” asked Bud.

“If one more breaks, we’re goners.”

The terrasphere continued to rise steadily as the winch reeled it in. Five feet, ten feet, one hundred feet. Like an accident spectator, unable not to look, Bud gazed through the porthole in the roof hatch, watching the cables. One was beginning to spread open like a flower, strand by strand—seconds from breaking.

Faster, Tom! Bud pleaded in his mind. Faster!

Then he gasped as the cable snapped in two. The cabin lunged and twisted—and steadied. The remaining cluster of cables still held!

“Okay,” Tom breathed. “Now one more and we’re goners!”

Bud was very quiet. We aren’t out of trouble yet, he thought. We still have two hundred feet to go and half the cables are gone!

The occupants of the sphere waited nervously, pulses thudding with fear. Finally, the cabin made the remaining climb and hung opposite the rim of the pit. Slowly, under Tom’s control, the hoist was swung around and in a few moments the cabin was resting securely on the chassis of the tank platform.

Tom and Bud hugged one another in relief and thankfulness. Then, as they climbed out, they stiffened. Nearby on the floor of the cave stood three figures in radsuits—Hank Sterling, Ry Cully, and Chow. Facing them was another small group, three men and a woman, none of them in protective gear, and one more radsuited figure.

Craig Benson!” Bud hissed. “I knew it!”

Benson turned. “Well hello!” he called over his suit com.

Bud tensed, ready for an angry retort and a bold forward charge, when he felt Tom clamp a firm hand on his wrist.

Startled, Bud paused for another look at the scene. Now he realized that the woman—revealed to be big game hunter Ophelia Wootenscarp—was standing next to Craig with her rifle aimed casually at the other three men: Hoplin, the man known as Cameron, and an African that neither Tom nor Bud had seen before.

Sterling, Chow, and Cully came running toward Tom and Bud.

“You’re safe! Both of you made it!” Hank cried in relief.

“Never doubted it!” Chow exclaimed. “But brand my green gas, whether you doubt it er not, sometimes things kin go bad on ya!”

In fits and starts the story was told. Three attackers had come thundering down the cave-corridor in a jeep, shotguns blazing. The fusillade had no effect on most of the tank, but part of the turret dome had shattered, and Hank had been winged by a bit of flying plastic, knocking him out. With the others helplessly pinned down in the passenger cabin, Hoplin had commandeered the turret, tossing Hank out into the dirt, where he had just regained consciousness—badly bruised but not in too bad a shape.

“We heard over the speakers what Hoplin said to you, Tom,” Ry Cully related. “We were absolutely distraught, but Benson here worked out a rather daring, if desperate, plan of action. Following his lead, the three of us had just made our break through the hatch, when― ”

“When Ophelia arrived on foot, rifle and all,” said Craig.

“Left my jeep a ways back up the tunnel,” said Miss Wootenscarp. “Strategy, element of surprise—you understand.”

“We assumed you were working with them,” Tom said.

“Oh yes, an entirely defensible assumption,” she said. “I didn’t mind leaving you with that impression—though I suppose my prerecorded lion-roars were a bit much.”

“So who are you really?” Bud asked.

“Who am I? Ophelia Wootenscarp!” She laughed. “But as to my occupation, it seems I am employed by the same government that gave you permission to travel here in Borukundi.” She gestured at Hoplin, who glared back evilly. “Ah, Mr. Hoplin—one should say poor Mr. Hoplin—he made a rather unfortunate career choice. A glance at history reveals that no one who works for General Boondah manages to live to a ripe old age.”

She dug down deep in her pocket, keeping an eye on her three prisoners. “Would you care to see a few little green acorns?” She withdrew her hand and opened it.

“Good lord!” exclaimed Ry. “Diamonds! Green diamonds!”

“Found only around and about this mountain,” said Wootenscarp. “The Supreme Commander can’t get enough of them, and has employed nasty persons like Mr. Hoplin—and Leopold Mkeesa over there—to discourage any competitive mining.”

“Mkeesa sought out the gang after I blabbed to him about the mountain phenomenon,” Craig Benson explained. “He already knew that Boondah was doing something here, and figured the information he had might be worth a nice reward.”

“The same fallacious logic that led Mr. Hoplin to steal your scientific study,” Wootenscarp remarked. “Mr. Mkeesa knows just enough science to have grasped the possibility of what I believe you term antiprotons rampaging under Mount Goaba. Yet he and Hoplin only saw it as an impediment to their incipient mining operation—they wanted to learn if there was a way to protect their digging equipment.”

“Then it was Mkeesa who left the third set of footprints,” muttered Bud, “not Craig.”

Craig’s intercom picked up Bud’s comment. “What! You mean you thought I was a backstabber?”

Tom asked Bud to explain his suspicions to finally clear the air. Craig burst out laughing.

“Well, I do have a confession to make, guys,” he said. “While you were all out searching the town, I felt restless, so I went out and walked down the road a hundred yards both ways, looking around in the grass and bushes. When I came back, I saw that I’d tracked mud on the carpet, so I changed my shoes. Since I’d disobeyed ‘doctor’s orders,’ I didn’t say anything.”

“What about that one?” asked Tom, indicating the man Craig had sketched as Cameron.

“A mineralogist from Brussels,” said Miss Wootenscarp. “Perhaps the only truly wicked mineralogist you will ever meet! His name is Gerhard van Hoondt—hides the accent very well, don’t you think, Mr. Benson?”

“I have many more questions,” said Tom; “but there’s something you should know, ma’am. This tunnel produces a great deal of ambient radioactivity. You must shield yourself right away.”

She nodded. “I’ve absorbed rather a lot,” she said; “but not a critical amount, by my reckoning. Obviously I’ve been nowhere near when that awful green gas has been spilling out.”

“Then you know about that?”

“Only that it is quite dangerous, yet scientifically interesting.”

After more discussion, Hoplin, van Hoondt, and Mkeesa were securely bound and delivered to the Sky Queen in the two jeeps, driven by Miss Wootenscarp and Arv Hanson, who explained how the marauders had driven him and Mandelia away from the cave entrance by grenade-blasts.

Reaching the Sky Queen himself, Tom immediately contacted his father and asked him to notify the proper authorities about the Hoplin gang, the green diamonds, and General Boondah’s role in the drama. He then accompanied the prisoners and their captors to the infirmary, where Doc Simpson examined them with the radioactivity-assessment device.

Miss Wootenscarp was well within the safe range. Mkeesa’s tissues showed a much higher level of radiation, but Simpson felt that he would probably pull through with an extended period of treatment.

Leopold Mkeesa smiled at Craig bitterly. “Perhaps they will allow me to take my treatments in the very same hospital in which we met,” he commented. “And then, to prison!”

The news for Hoplin and his crony was grim. “You have exposed yourself to radiation on and off for months,” Simpson told them; “and lately you spent hours searching for traces of the diamonds inside the cave—even shortly after the emission of the antiproton gas. I take no pleasure in telling you that there is nothing to be done for you.”

The Belgian began to protest in terror, but Hoplin only growled at him, “Shut up!”

After the prisoners had been removed to three of the ship’s lockable cabins, Doc Simpson said to Tom, “Skipper, Mkeesa’s physical reaction to his dose of radiation is rather unusual. He was exposed to almost as much radioactive material as the others, yet his body seems to have sloughed it off somehow. It’s a medical mystery worth looking into.”

“No big mystery,” said Chow. “I know how he did it—he told me while he ’as waitin’ t’go in fer that test.”

“What did he say?” asked Mandelia and Tom, speaking almost with one breath.

Chow beamed at having the upper hand for one fleeting moment. “Hold your horses an’ I’ll tell you! It’s herbs! This here jungle’s full o’ all kinds o’ queer plants, an’ they gets more extra-strange the closer you go to that taboo mountain. The man told me how he tried t’ keep up a real African diet even out here, chewin’ on a lot o’ those things an’ usin’ ’em to cook with.”

Doc Simpson’s face lit up in pleasure. “Chow, I believe you may have stumbled on a marvelous discovery!”

“Shore did!” Chow snorted. “Folks fergit I got more uses around here than just t’ make people laugh an’ eat their dinner!”

“And yet, Chow, you do have a well-developed ‘talent to amuse’,” commented Ry Cully with a smile.

“Naw—jest a little extra snootch of Texas charm!” Chow retorted.

In the days that followed, Tom was in close contact with his father, who in turn had briefed the United States government on the behavior of General Boondah and the perilous promise of the mountain of the spirit-gods. Ultimately Mr. Swift reported that the danger of allowing antiproton matter to get into the hands of a man like the Supreme Commander had finally inspired the international community to settle the ambiguous status of Borukundi.

“Last night Boondah fled the country,” said Damon Swift. “An international force will be arriving soon to rid the countryside of Boondah’s guerrillas, and establish something like a civil government that includes both the Maba and the Onari tribes.”

“Is Borukundi to be an independent state?” Tom inquired.

“Perhaps in time,” replied Mr. Swift. “For now the three countries that border it have decided to co-administer it in the name of the United Nations.” He added that an international presence around Mount Goaba would allow its thorough scientific investigation—and carefully monitor the whereabouts of its deadly antiproton matter.

After signing off with his father, Tom turned to Bud and said thoughtfully, “Someday I imagine a large research facility will be located here, to study the chemical magic going on under that mountain.”

“Maybe doping out how Inertite and Exploron work will keep you busy for a while, genius boy,” Bud said. But in this case he was a poor prophet, for events in the far depths of space were already conspiring to lead Tom and Bud on an astonishing new journey—Tom Swift on The Phantom Satellite.

Too bad, though, about having to drop that instrument package inside the mountain,” continued Bud. “I know how badly you wanted those rock specimens.”

“Don’t worry about that,” Tom replied, throwing an arm around Bud’s athletic shoulders. “Who says we can’t go back for more?”