Ames tried another tack. He asked how many people had known about the expected arrival of the brain energy from s.p.a.ce. This was harder to answer, but as Tom and his father enumerated the persons, it did help to narrow the circle of suspects.
Besides the Swifts, Chow, Phyl, Ames, and George Dilling, there were three groups who had had access to the information. One was the radio operators at the s.p.a.ce-communications laboratory. Another consisted of Arv Hanson and Hank Sterling and the workmen who had taken part in building the energy container. The last group, which also included Hank and Arv, were the technicians who had actually gone to the hillside to await the visitor from Planet X.
Tom scowled. "None of those people would pull such a trick, Harlan--any more than the ones like you and Arv and Hank who are above suspicion.
Most of them could have easily obtained the news without going through such a rigmarole."
Mr. Swift nodded. "Tom"s right. Unless, of course, they had some urgent reason for wanting to find out as soon as possible."
"Which makes me think it may have been an outsider after all," Tom argued. "Remember, the Brungarians may have intercepted the code messages to or from our s.p.a.ce friends." After a moment"s silence, he added gloomily, "Whoever the caller was, he knew the energy was arriving. And now he knows it"s here!"
Bud interjected, "Well, if he was a Brungarian agent and he"s hoping to steal the brain energy, one thing"s sure. No earthquake will demolish this place as long as the energy is here at Enterprises."
"A comforting thought, Bud," Mr. Swift commented with a wry smile.
Again Tom frowned. "At any rate, Harlan, see if you can get a line on that impostor."
Ames departed to begin a thorough check of all personnel at the plant who might have been implicated. Bud went on an errand, as Tom began showing his father the accomplishments of the s.p.a.ce robot.
"We"ve christened him Exman," Tom said.
By means of the electronic brain, he made the visitor do a number of maneuvers in response to orders.
"Wonderful!" Mr. Swift exclaimed, greatly impressed. "Let"s see if he can use his caterpillar treads as well as he does the wheels."
Tom brought a small flight of portable aluminum stairs which he used for reaching up on high shelves or tinkering with outsized machines. Tom was uncertain at first how to code the command, having no symbol for steps or stairs. Finally he moved Exman to the bottom of the steps and signaled simply: _Go up!_
Exman paused for a moment, then attempted the ascent. His caterpillar tracks clawed their way up the first step. Then, gingerly, he essayed the next. The robot body tilted, but its gyro kept it from toppling over.
"Bravo!" Mr. Swift applauded encouragingly. But the next instant Exman gave up! He slid back to the floor again with a heavy b.u.mp. Then he began whirling and darting about madly.
"Good night! Exman"s gone berserk!" Tom cried.
Now wafts of smoke could be seen issuing from the robot"s wheels. He was banging wildly about the laboratory, leaving a trail of havoc.
Bud, who had returned, opened the door to come in. Instantly Exman lunged toward him, antennas sparking fiercely and wheels smoking. Bud slammed the door hastily.
The Swifts, too, found it wiser to take cover. They crouched behind a lab workbench until the frenzy was over. Presently Exman subsided and rolled to a complete standstill.
"Good grief!" Tom stood up cautiously and eyed the creature. It made no further move. Bud poked his head through the doorway for a wary look, then re-entered the laboratory.
"What made him blow his top?" Bud asked.
Then Tom heard a quiet chuckle from his father. "Actually, boys," the elder scientist said, "I think we should be encouraged."
"_Encouraged?_" Tom stared at his father.
[Ill.u.s.tration (Tom Jr. and Tom Sr. watch as Exman tries to climb stairs)]
Mr. Swift nodded. "Yes, the whole thing was rather a noteworthy reaction. I believe Exman was displaying a fear complex about navigating up those stairs."
Tom gasped, then broke out laughing. "Dad, you"re right! I"ll bet when its body tilted over, the brain wasn"t sure whether the gyro would keep it from being wrecked. It just shows Ole Think Box is getting more human all the time!"
Bud ventured to pat Exman on its "back." "Relax, kid," he said with a chuckle. "You"re among friends and we wouldn"t dream of letting you get hurt. You"re too valuable!"
Mr. Swift stroked his jaw thoughtfully. "Valuable, yes, if we can only get it to communicate. Tom, I believe the first project we should work on is a way to make Exman talk."
After the debris had been cleaned up, the two scientists pulled up stools to the workbench and began to discuss the problem. Bud, seeing them absorbed, and realizing the discussion would soon be far beyond his depth, snapped a grinning salute at Exman and quietly left the laboratory.
"Dad, the toughest part won"t be the speech mechanism itself," Tom pointed out. "There are several ways we could handle that--by modulating a column of air, for instance, or by some sort of speaker diaphragm. The real stumper will be how to teach him our spoken language."
Mr. Swift nodded. "I"m afraid you"re right. If the inhabitants of Planet X communicate telepathically, or by some sort of wave transfer, they may have long since forgotten any concept of a spoken language."
The Swifts batted several ideas back and forth. Then Tom snapped his fingers.
"Wait, Dad! We have the answer! The electronic brain!"
Mr. Swift"s eyes lighted up. "Of course! The machine already translates the s.p.a.ce code into written English. All we need do is add a device to convert the machine"s impulses into sound!"
In two hours the Swifts had put together a mechanism designed to work through a tape recorder. This was hooked up to the electronic brain.
After recording for several moments, Tom reversed the tape and switched on the playback. A squeaky jumble of noises could be heard. But one word seemed to come through fairly distinctly. "Universe!"
"It"s talking!" Tom cried out.
"Trying to, but not succeeding very well," Mr. Swift said.
Nevertheless, the two scientists were jubilant at this first breakthrough. Eagerly they began making adjustments--both on the electronic-brain hookup and the converter mechanism. Tom was just about to switch on the tape recorder again when the telephone rang.
The young inventor was annoyed at being interrupted at such a crucial moment, but picked up the phone. "Tom Swift Jr. speaking."
"You have an urgent call from Washington," the operator informed him.
"Just a moment, please."
Bernt Ahlgren was calling from the Pentagon. The defense expert"s voice was strained.
"Tom, there"s just been another attempt to cause an earthquake here in Washington!"
Tom gasped. "What happened?"
"It failed, thanks to you. But Intelligence believes an attempt will be made on New York City very soon. We need your help to stop it. How near completion are the other shock deflectors?"
Before Tom could answer, he heard excited voices at the other end of the line. Then Ahlgren broke in again abruptly.
"A news flash, Tom! The Walling range-finder plant has been demolished by an earthquake!"