CHAPTER XVII
AN URGENT WARNING
Mr. Swift looked on eagerly as Tom explained and demonstrated his touchapparatus. By moving a pantograph control, Tom was able to manipulatethe claws like a hand with fingers. Whenever they touched any material,the brain gauges instantly registered an electrical reaction inside thesphere.
The swing of a voltmeter needle showed how firmly the substance resistedthe claw's touch, thus indicating its hardness or softness.
"With a computer device, such as we planted in Exman," Tom went on, "thebrain would also be able to assimilate the textural pattern of anysubstance."
"Wonderful, son!" Mr. Swift exclaimed. "I hope I can do as well withthis artificial sense of sight I'm working on."
Another hour went by before Mr. Swift was ready to test his ownarrangement.
"You've probably heard of the experiments conducted with blind persons,"he told Tom. "By stimulating the right part of their brain with a leadfrom a cathode-ray-tube device, an awareness of light and dark can berestored."
Tom nodded.
"Well, I'm using the same principle," Mr. Swift went on, "but with asort of television camera scanning setup."
He asked Tom to draw the drapes and shut off the room lights, throwingthe laboratory into complete darkness, except for the weirdly glowing"brain" in the glass sphere. Then Mr. Swift shone a flashlight at thescanner. The brain responded by glowing more brightly itself!
Next, after the drapes were opened again and the overhead fluorescentlights switched on, Mr. Swift painted a pattern of black-and-whitestripes on a large piece of cardboard. He held this up to the scanner.
Visible ripples of brightness and less-brightness passed through theglowing ball of energy inside the sphere. It was reproducing the stripedpattern!
"Dad, that's amazing!" Tom said with real admiration.
Mr. Swift shook his head. "Pretty crude, I'm afraid. The brain energy byitself can't take the place of a picture tube in a TV receiver. What weneed is an analog computer to sum up the scanning pattern picked up bythe camera tube and then pass this information along in code form."
Before Tom could comment, the alarm bell rang on the electronic brain.The Swifts dropped everything and rushed to the machine.
"Wonder if it's Exman?" Tom exclaimed.
The answer was quickly revealed as the keys began punching out theincoming message on tape. At the same time, a flow of strangemathematical symbols flashed, one after another, on the lightedoscilloscope screen mounted above the keyboard.
Tom and his father read the tape as it unreeled.
SPACE BEINGS TO SWIFTS. REQUEST INFORMATION ON PROGRESS AND RESULTS OF ENERGY SENT TO YOUR PLANET.
After a quick consultation with his father, Tom beamed out the reply:
WE ARE PLEASED WITH RESULTS SO FAR. FURTHER EXPERIMENTS NOW GOING ON. REQUEST VISIT TO CONTINUE LONGER THAN TWENTY-ONE DAYS AS PLANNED.
Hopefully the Swifts stood by the machine. Would their space friendsagree? As the minutes went by without a response coming through, fatherand son exchanged anxious glances.
"They've _got_ to let Exman stay, Dad!" Tom said.
Mr. Swift nodded. "I'm afraid, though, the space beings have decidedotherwise. They--"
He was interrupted by the ringing of the alarm bell. "Message, Dad!" Tomsaid tersely.
A moment later they were overjoyed to see three words appear on thetape:
VISIT EXTENSION GRANTED.
Relieved, the two scientists went back to work on their sensingexperiments. Twenty minutes later the signal bell rang again on theelectronic brain.
"This time it _must_ be Exman!" Tom cried.
The unreeling tape quickly bore out his guess.
EXMAN TO SWIFTS. TWENTY-FOUR-HOUR EARTHQUAKE UNDER HIGH LOYALTY.
"What!" Tom stared at the tape, his brow creased in a puzzled frown."That 'twenty-four-hour earthquake' bit must mean he's warning us that aquake will occur in twenty-four hours. But what about the rest of it?"
"Hmm... 'Under high loyalty.'" Mr. Swift was as baffled as Tom. Hestudied the message for several minutes. It seemed highly unlikely thatthe electronic brain had made an error in decoding. Any new oruntranslatable symbol caused a red light to flash on the machine.
"I think the only thing we can do is signal Exman and ask for aclarification, Tom," Mr. Swift decided at last.
Tom agreed. He beamed out a hasty code signal:
EXPLAIN MESSAGE.
Seconds later came Exman's reply. It was identical with the firstmessage:
TWENTY-FOUR-HOUR EARTHQUAKE UNDER HIGH LOYALTY.
Tom and Mr. Swift stared at each other anxiously.
"Good night, Dad! This is horrible!" Tom exclaimed. "Exman sends usample warning of a disaster and we're stymied!"
[Illustration (Tom Jr. and Tom Sr. read a message from Exman)]
"Hi! What's going on, you two?" asked a merry voice. "More heavythinking?"
Sandy Swift stood smiling in the doorway. The smile gave way to a lookof concern as Tom explained the crisis.
"How dreadful!" Sandy gasped. "We _must_ figure out what it means!...Wait a minute!"
Tom looked at her expectantly. "Got an idea, Sis?"
"Well..." The pretty, blond teen-ager hesitated. "You don't supposeExman might have been translating some foreign words with a meaningsimilar to 'high loyalty'? For instance, high loyalty could mean 'goodfaith.' I know that in Latin 'good faith' would be _bona fide_."
"Sandy! You've guessed it!" Tom crossed the room in a single bound, gavehis sister a quick hug, and whirled her around. "Exman must mean theBona Fide Submarine Building Corporation! He didn't dare risk telling usthe exact translation."
"Of course!" Mr. Swift was equally jubilant. But his face was grave ashe added, "The company's located on the West Coast close to the SanAndreas fault. Tom, a quake in that area could be devastating!"
"You're right, Dad," the young inventor replied. "I'll call Dr. Milesand Bernt Ahlgren at once!"
The telephone conversation that followed was grim with tension. Bothgovernment men begged Tom to take personal charge of thequake-deflection measures. Dr. Miles pointed out that tremors along thefault might trigger off a chain of quakes amounting to a nationaldisaster.
After a hasty discussion, Tom agreed that he should station himself atthe Colorado site, rather than at the West Coast Quakelizorinstallation. This would give him broader scope for damping out shockwaves across the continent.
"I'll fly out immediately!" the young inventor promised.
Ahlgren, meanwhile, would flash orders to the Bona Fide Company and tocivilian officials to have the entire area evacuated as soon aspossible.
Hasty preparations were made for Tom's departure. He telephoned theairfield to have a jet plane with lifters readied for take-off. He alsohad Bud paged over the plant intercom. The copilot came on the run. Whenhe heard the news, he was eager to accompany his pal.
"Listen, you two! I insist you have something to eat before you leave!"Sandy declared.
Tom was impatient over any delay. When Sandy proceeded to call Chow, theold Texan solved the problem by volunteering to go along as cook.
A short time later Chow came jouncing out to the airfield astride amotor scooter, hauling a cart loaded with supplies.
"Good grief!" Tom said, unable to suppress a grin. "We'll be backtomorrow, unless something goes wrong!"
"Bring food--that's my motto," Chow retorted, "like any good cook."
Minutes later, after a parting handshake from his father and a worriedkiss from Sandy, Tom sent the sleek jet racing down the runway fortake-off. Soon they were air-borne and heading westward. Chow served atasty meal en route.
It was still daylight when the jet landed vertically in the Coloradocanyon. The government crew manning the installation, and the Swifttechnician who had relieved Art Wiltessa as trouble shooter on thesetup, greeted them eagerly.
"Looks as if we're in for a real test, Tom," said Mi
ke Burrows, theengineer in charge.
"Let's hope we pass!" said Tom, holding up crossed fingers.
He checked every detail of the Quakelizor, power plant, and thecommunications gear. He opened an inspection panel in each of thedual-control spheres and tuned the kinetic-hydraulic units so as tostep up the working pressure of the four powerful drivers.
"Well, all we can do now is wait," the young inventor muttered, wipinghis arm across his forehead.
Tom passed the night in a fitful sleep, half expecting to be wakened atany moment by the stand-by crew on watch. No alarm occurred, however.
Dawn broke, and Chow delighted all hands with a hearty breakfast ofbacon, eggs, and corn fritters. More hours of waiting dragged by.
"What time do you think the attack will occur?" Bud asked.
Tom shrugged. "The 'twenty-four-hour' business may have beenapproximate. But I'd say from two o'clock on is the danger period."
The young inventor checked frequently with Washington and the othercrews stationed around the country. Suddenly the radiotelephone operatorgave a yell.
"Your father is on the line, skipper!"
The scientist was calling from the receiver-computer headquarters atEnterprises. "Exman has reported a quake pulse will be sent in sevenminutes--at 21.36 G.M.T."
"I'm ready, Dad," Tom said, then asked for various technical detailsbefore hanging up.
He passed the word to the crew and glanced at his watch. A hasty,last-moment inspection was carried out, every man checking certaindetails of the setup.
Soon the pulsemakers began ticking inside the dual-control spheres asthey picked up the frequency signal by radio. Tom studied the gaugedials.
Tension mounted rapidly among the waiting group. The same thought wasthrobbing through every mind:
_Was the nation on the brink of a terrible disaster? Or would TomSwift's invention safeguard the threatened area?_
As the deadline approached, Tom pushed a button. The mighty hydraulicdrivers throbbed into action, sending out their pulse waves across thecontinent!