_Stop!_ Tom signaled frantically. Again Exman obeyed the order.
"It"s like a mischievous kid," Bud said.
Almost as if in defiance, Exman scooted off in another direction. Then it stopped abruptly and swiveled around, one of its antenna arms knocking a Bunsen burner to the floor as it did so.
_Come here!_ Tom signaled. As the culprit approached, he added sternly, _Stop where you are. And stay there until you receive further orders._
This time Exman stood patiently, awaiting the next signal. Bud got a brush and dustpan, and the boys cleaned up the broken test tubes and replaced the burner on its shelf.
Then Tom began feeding more complicated instructions to Exman through the electronic brain. He guided him through a number of dancelike movements and other drills, and got him to send out a wave of heat which the boys could instantly feel. Tom was even able to make the robot aim its wave energy so as to short-circuit a switch on an electrical control panel.
Tom was both pleased and excited. "Bud," he exclaimed, "the brain reacts as quickly as that of a highly intelligent being! Just imagine--without any sort of decoding equipment, it can pick up and _understand_ the radio signals I beam out to it!"
"What we need now," Tom went on, "is a simple language to get our ideas across to Exman without having to use the electronic brain all the time.
That means I must find a way to give Exman senses as we humans have--smell, touch, sight, hearing, taste. Then it could receive the same reactions we do and talk directly to us!"
"Sounds like quite an order," Bud said wryly. "Speaking of which, how about us phoning Chow an order for breakfast?"
He did so, and a short time later Chow wheeled a food cart into the laboratory. As he dished out man-sized helpings of ham and eggs, the cook kept a wary eye on Exman. Tom was putting the robot through a few more lively maneuvers.
"A good meal"d calm down Ole Think Box," Chow observed grumpily. "But what do you feed that there kind o" contraption?"
"Well, not gum, that"s for sure!" Bud teased. After tasting his first forkful of food, he gasped, "And none of this ham!"
Jumping up from his lab stool, Bud began whirling, dancing around, and flapping his arms as if he were burning up.
"Help! Help!" he yelled. "Chow"s poisoned me--just like he did Exman!"
Chow"s leathery old face paled under its desert tan. "Great snakes, Tom!" the Texan gulped. "Have I really pizened him? Maybe we should call Doc Simpson!"
Doc was the medic in charge of the Enterprises infirmary.
Tom was unable to keep a straight face. "Better call someone with a strait jacket--or a b.u.t.terfly net!" he said, quaking with laughter. "I"m afraid he"s just pulling your leg, Chow!"
Chow"s jaw clamped shut like a bear trap and he glared at the pirouetting young flier. Bud collapsed on his stool, doubled over with mirth.
"Sorry, old-timer," he gasped. "I just couldn"t resist!"
"Okay, Buddy boy," Chow said darkly. "And mebbe I won"t be able to resist gettin" even one o" these days!" The cook stumped out of the laboratory in his high-heeled cowboy boots, a picture of outraged dignity.
"Better watch out, pal!" Tom warned with a grin. "Just remember: it"s never smart to bite the hand that feeds you!"
"I guess you"re right," Bud agreed, wiping away the tears of laughter.
"I"ll remember, just as long as Chow promises not to serve us any more armadillo soup or rattlesnake salad!"
Chow"s fondness for experimenting with weird dishes was a standing joke around Enterprises.
The boys ate their meal hungrily. As they were finishing, Tom glanced at the big clock on the wall. It was now well past eight o"clock.
"Wonder why Dad hasn"t come to the lab," he remarked. "I"d better call and find out if he"s all right."
Tom picked up the telephone and asked the operator for the direct line to the Swifts" home. His father answered.
""Morning, Dad!" Tom greeted him. "I thought after your call last night, you"d be over bright and early to see our visitor. He"s already--"
"What are you talking about, son?" Mr. Swift broke in. "I didn"t phone you last night!"
CHAPTER XIII
DISASTER STRIKES
Tom was thunderstruck. "You didn"t phone me? But, Dad, I got the call--I definitely heard your voice!"
"That"s impossible," Mr. Swift insisted. "Believe me, son, I slept soundly from the time I turned in until a little while ago."
There was a moment of stunned silence as both Swifts realized that the telephone call had been faked! Then Tom exclaimed:
"Dad, this is serious!"
"Deadly serious, I agree," his father replied. "Are you calling from your lab?"
"Yes!"
"Stay there. I"ll be right over," the elder scientist said.
When Mr. Swift arrived, Tom related his conversation with the mysterious caller. His father listened with worried eyes and a puzzled frown.
"It"s bad enough that an enemy was able to get the information," Mr.
Swift remarked. "But, potentially at least, it"s even more dangerous that he was able to imitate my voice so well. If he could fool you, Tom, he could fool anyone!"
"Are you thinking the same thing I am, Dad?"
"That it may have been some insider here at Enterprises?" When Tom nodded, his father gravely agreed. "Yes, son, it does look that way. To imitate my voice convincingly, it would almost certainly have to be someone who"s had close contact with us--either at the plant or here in Shopton."
The thought of a traitor at the experimental station was repugnant to the Swifts and to Bud as well. Not only were all employees carefully screened, but there was a close, almost family relationship among those who took part in the exciting scientific ventures at Swift Enterprises.
Tom called Security and asked Harlan Ames to come over to the laboratory at once. The security chief arrived within moments. Quickly Tom filled him in on the details of the puzzling telephone call.
"Think back, skipper," Ames urged. "Was there anything at all you can remember about the voice that might give us a tip-off? I mean, was it deep, or maybe a bit higher-pitched than you expected? Or anything about the way the caller p.r.o.nounced his words?"
Tom shook his head. "Nothing. That"s the trouble. He spoke only a couple of sentences, but so far as I knew, it _was_ my father calling!"
"Hmmm." Ames frowned. "What about background noises?"
Tom thought hard. "None. If I had detected any special sounds during the call, I"m sure they would have stuck in my mind."