_ CHAPTER XII. EXMAN TAKES ORDERS
A strange sight greeted Tom's and Bud's eyes. In the first rays of sunlight, the space robot was moving back and forth about the laboratory in wild zigzag darts and lunges.
As he rolled toward a bench or other object, the brain energy seemed to send out invisible waves that knocked things over! Already the floor was strewn with toppled lab stools, books, and broken test tubes. The heavy thud had apparently been caused by a falling file cabinet.
"Stop him!" Bud yelped.
Exman was heading straight for a plate-glass window! Reaching from floor to ceiling, the glass formed one entire wall of the laboratory.
"Oh, no!" Tom tensed, realizing that it was hopeless to try to stop Exman in time.
But an instant later, the rolling robot stopped of its own accord, as if registering the fact that its energy waves were now striking a fragile surface. The thick pane of glass vibrated in its frame.
"Good grief!" Tom wiped his brow. "Let's corral that thing before he wrecks the whole lab!"
Exman was already rolling off on a new tack. The two boys managed to grab him before more harm was done. The brain energy in its container seemed to calm under their touch.
"What in the name of space science triggered it off?" Bud wondered out loud.
"Time. It must have reacted to the passage of time," Tom conjectured. "I suppose it just decided to explore this place." He added a bit nervously, "The sooner we can communicate with this energy, the better!"
"But how?" Bud asked.
Tom's brow furrowed. "Say, I wonder if Exman might understand a direct order?"
Tom backed a few paces away from the space robot, then said in a loud, clear voice, "Come here!"
Exman remained fixed to its spot.
"Move right!" No response. "Move left!" Still no response.
"Guess you're not getting through, skipper," Bud commented with a grin.
"No," Tom agreed. "I can't predict what kind of energy this brain will respond to. Being only energy, it must respond to other energy and sound is our form of energy. The problem is the same as with radio waves, which are also energy. We must figure out how we can vary the energy, so it can transmit information to Exman."
"What _do_ we try?" Bud asked. "Or is it hopeless?"
"I'll try communicating with it via the electronic brain, which I have adapted to fit this problem."
The boys cleaned up the wreckage caused by Exman in his dawn venturings. Then Tom went by jeep to the computer laboratory, made connections to his electronic brain, and wired it for remote control. Then he returned to the private laboratory. There Bud watched as he hooked up the leads from the computer to a transmitting-receiving decoder with a short-range antenna.
"Speak, O Master!" Bud said, imitating a squeaky robot voice. "Sound off loud and clear!"
Tom grinned and tapped out a command on the keyboard: _Move backward._
Exman rolled backward! Bud gave a whoop of delight.
Tom signaled: _Move forward._ Obediently Exman rolled toward him.
_Stop._ Exman stopped.
"Hey, how about that?" Bud exclaimed happily. "It really savvies those electronic brain impulses!"
"And minds them--which is equally important," Tom added.
A moment later the brain energy seemed to become impatient. It spurted off in its wheeled container toward a laboratory workbench.
_Crash!_ A rack of test tubes went sailing to the floor with an explosion of tinkling glass.
_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 butterfly 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!" _