car? It's only a few miles away, isn't it?"

"I'll send the plant nurse to him," Simkins said. "As for going to town, take a look at the parking lot." He pointed with a jerk of his thumb. The cars on the lot had been smashed into junk by bricks from a collapsing wall of one of the buildings. "And the only truck we had available was in that burning shed," the superintendent added bitterly.

"Tough break," Tom sympathized. "Anyhow, we want to help. Got a job for us?"

Simkins was only too glad to put Tom's quick mind and keen technical know-how to use. Within minutes, Tom was in charge of clearing away rubble and extricating anyone who might be trapped inside the buildings. Bud organized a fire-fighting crew to keep the blaze in the shed from spreading.

The telephone line was soon repaired and a steady stream of rescue vehicles began arriving from Harkness—fire trucks, three ambulances, and private cars driven by volunteers.

Two hours later there was nothing more Tom and Bud could do at the disaster scene and they hitched a ride into Harkness. The town had suffered some damage, though only slight compared to the destruction at the plant.

"The center of the quake was right under Faber Electronics," Tom remarked.

From a pay telephone, he called Swift Enterprises in Shopton. This was the experimental station where he and his father developed their many amazing inventions. Tom asked the operator to send a helicopter immediately to pick them up. He also called home and spoke to his sister, Sandra.

"What a relief!" Sandy gasped. "We heard a bulletin about the quake over the radio!"

"Don't worry, Sis. Tell Mother and Dad that we're okay," Tom said. "We'll be home in a jiffy—with big appetites!"

The helicopter arrived within twenty minutes at the place Tom had named. After landing at Enterprises, the boys drove to the pleasant, tree-shaded Swift home on the outskirts of town.

Mrs. Swift, a slender, petite woman, tried not to show concern when she saw the boys, bruised and disheveled. "I'm so thankful you're both safe!" she murmured.

Blond, blue-eyed Sandy, who was a year younger than Tom, had invited her friend Phyllis Newton to the house for dinner. Phyl, a pretty, dark-haired girl, was the daughter of Mr. Swift's long-time friend and business associate, "Uncle Ned" Newton. The two girls were as much upset as Tom's mother.

Tom laughed. "We're not stretcher cases," he said. "Why, one of the ambulance doctors checked us out."

Bud groaned. "Why did you have to go and spoil it?" he complained jokingly. "I was all set for Sandy's cool soothing touch on my fevered brow!"

Mr. Swift came into the living room just then and told Tom how worried Mrs. Swift and Sandy had been. "I tried to assure them that you and Bud can take care of yourselves in any crisis." He smiled guiltily as he added, "But I must admit I was more than a little concerned myself."

As Tom grinned, the resemblance between him and his father was very evident. Both had the same clean-cut features and deep-set blue eyes, although Tom Jr. was lankier and taller.

After the two boys had showered and changed their clothes, Mrs. Swift served them a delicious, hot meal. While they ate, Mr. Swift managed after some difficulty to get a call through to the Harkness Hospital. His face was grave as he hung up.

"Mark Faber is not expected to live," the elder inventor reported. "A pity. He's a great scientist."

Tom nodded unhappily. Sandy, to take her brother's mind off the disaster, said, "Dad, tell Tom and Bud about the visitor who's coming."

"A visitor?" Tom looked at his father.

"From another planet," Mr. Swift revealed.

Both boys were amazed and excited. "Wow!" Bud gasped. "Male or female? Human or animal?"

Mr. Swift's eyes twinkled. "None of those," he replied as the boys stared, mystified.

CHAPTER II

THE MYSTERIOUS HITCHHIKER

Tom and Bud were bursting with curiosity. Although the Swifts had been in radio contact with creatures from outer space for many months, this was the most exciting news yet!

On one occasion, the unknown beings had moved a small asteroid—the phantom satellite Nestria—into orbit about the earth. Later they had sent strange samples of the animal life of their planet, aboard orbiting missiles, to be studied by the Swifts. They had also helped Tom, Bud, and Mr. Swift a number of times when their lives were at stake while on daring voyages beyond the earth. What was their latest intention?

The telephone rang and Sandy went to answer it.

"For Pete's sake, Dad," Tom pleaded, "don't keep us in suspense! Who or what is this visitor?"

Mr. Swift smiled at the boys' baffled expressions. "The fact is that a message came through today that—"

He was interrupted by Sandy who had come to the door. "The phone call's for you, Dad. Long distance from Washington."

Bud groaned as Mr. Swift went off to take the call. "It's a conspiracy," Bud said. "Everyone's ganging up to keep us from finding out about that mysterious visitor!"

Tom grinned. "We lasted through an earthquake this afternoon, pal," he said consolingly. "I guess we can last through a phone call."

Inwardly Tom was as impatient as Bud about the exact nature of the message.

Several months ago, the space creatures had sent their first communication in the form of mathematical symbols carved on a black missile which had landed on the grounds of Swift Enterprises.

Tom and his father had decoded the symbols and beamed out a reply over a powerful radio transmitter. Later messages had been picked up by radio telescope and converted to appear as symbols on the oscilloscope screen.

"Sandy must know what it's all about," Bud broke in. "She's the one who first mentioned the visitor."

"Of course I know," Sandy said mysteriously. "So does Mother and so does Phyl. But don't think we're going to give it away!" she added teasingly.

Tom and Bud cajoled the two girls and Mrs. Swift for further information. But Sandy and Phyl only shook their heads, obviously enjoying the situation.

"At last we're getting back at them for the way they've neglected us!" Phyl said, her brown eyes sparkling with laughter.

"Come on, Mother!" Tom said. "Be a sport. You tell us!"

But Mrs. Swift too shook her head. "I'm sorry, Tom," she demurred gently, "but I think the girls are right. I'll say this much, though," she relented, "it will be the biggest challenge that Tom Swift Jr. and Sr. have ever faced!"

"Whew!" Bud remarked as the two boys glanced at each other. "That must mean it's plenty big news! It would have to be, skipper, to top all the other jobs you and your dad have taken on!"

Conquering outer space, probing the ocean's secrets, drilling to the earth's core—these were only a few of Tom Swift's many exciting exploits.

In his first adventure, Tom, in his Flying Lab, had gone to South America to fend off a gang of rebels seeking a valuable radioactive ore deposit. In his most recent challenge, Tom had defied the threats of Oriental killers determined to ferret out the secret of the Swifts' latest space research.

As the two boys silently recalled the exciting events of the past months, Mr. Swift returned to the living room.

Tom and Bud leaned forward in their chairs. "Well, boys,"