Alexander Key
Sprockets: A Little Robot

    To My Son, who naturally knows much more about robots than I, and keeps me properly informed.
    To Dr. Isaac Asimov, the father of modern robotics who conceived the positronic brain, I offer no apologies, but much respect and many thanks.

    Chapter 1: He Escapes
    Chapter 2: He Is Adopted Temporarily
    Chapter 3: He Becomes Partially Educated
    Chapter 4: He Has Trouble in Mexico
    Chapter 5: He Meets Professor Katz
    Chapter 6: He Finds the Saucer
    Chapter 7: He Goes Space Traveling
    Chapter 8: He Visits the Dark Side
    Chapter 9: He Encounters Moon Bats
    Chapter 10: He Uses His Buttons

Chapter 1: He Escapes
    Sprockets was born on the assembly line at the robot factory owned by the Consolidated Mechanical Men Corporation. His birth, or rather his putting together, was entirely an accident, and was the last thing anyone wanted. Here is how it happened:
    The assembly line at the robot factory was a mile long and possibly longer, for it had to handle a million different parts – rods and wires, nuts and bolts, bulbs and sockets, springs, sprockets, and little wheels and cogs, not to speak of nine hundred thousand other things that go into a robot. Whenever the big boss robot pressed the button at the beginning of the line, there would be a mighty whirring clatter, a quick zipping and purring, and a thousand mechanical hands would begin punching, twisting, turning, driving, pounding, brazing, and fitting things together. Then like magic, zip, zip, zip, one new robot after another would take shape on the speeding belt. That is, this zip-zipping was usually the way it went when new robots were ordered.
    But on this dismal day of days at the robot factory something went wrong. Perhaps the big boss robot missed a zip. Perhaps a spring was sprung or a spark went sput. Anyway, a roll of metal didn’t roll, and suddenly there just wasn’t enough metal for the assembly line to turn out the usual full-size, clanking, half-ton model that was the specialty of the Consolidated Mechanical Men Corporation.
    The assembly line did the best it could with the scraps on hand, but the only thing that appeared on the mile-long moving belt was one little pint-size model no larger than a smallish boy with a biggish head. Nor was that the worst of it.
    The worst of it (which in reality was the best of it) was his brain. The ordinary brain box, used for ordinary robots, wouldn’t fit the new shape of this robot’s head. That, however, did not bother the assembly line. It merely reached forth a tentacle and plucked down a special box from a special shelf marked SPECIAL BRAINS, TO BE USED ONLY ON SPECIAL MODELS. It was a genuine Asimov Positronic Brain that had taken a whole year to make, for it contained twenty trillion microscopic printed circuits. Into the little robot’s head went the special brain, and he plopped off the end of the assembly line all ready to be oiled, numbered, inspected, registered, given his orders, crated, and shipped away.
    It was now that the trouble started.
    The inspector was a real man, not a mechanical one. At the sight of Sprockets, who was yet to be named, his eyes widened. Then angrily he stopped the machinery and bellowed for his assistant.
    “What’s the matter with this factory?” he roared. “Can’t it do an honest day’s work without wasting good parts? Call the salvage robots! Have them haul that junk bundle of sprockets into the salvage room and take it apart!”
    Sprockets not only heard what was said, but he understood it because, in rolling off the assembly line, his switch had been accidentally turned on. It was like coming awake and finding himself alive. In an instant he sat up, ticking like a clock. His eyes lighted and the row of buttons across his forehead flashed with color. The words “salvage” and “take it apart” shot with deadly meaning through the upper circuits of his brain. In less time than it takes for a human to bat an eye, he was on his little feet and running.
    Haul him to the salvage room and take him apart, would they? Oh, no! Never as long as he had a spark left in his atomic battery!
    Now, a robot is not supposed to run away or to disobey authority. But Sprockets was not actually disobeying anyone, because as yet he had not been given a proper registered name or a number, and no one thought to speak to him directly or give him orders. And a robot – especially one with an Asimov Positronic Brain – knows he is a very valuable mechanism and must protect himself from harm.
    So Sprockets ran. Behind him all he heard were the hoarse cries of men and robots calling to each other. “Stop him! Stop him! Don’t let him get away!” This, naturally, only made him run faster.
    He darted through the first open door. Three big robots clanked and thumped close at his heels. He evaded them by dashing under a table and streaking down a long passage and through a succession of doors. Suddenly, before he realized where he was, he found himself outside.
    It was night. Sprockets had never seen night and the city before nor traffic on a busy street, but his special brain knew about such things from the basic learning tapes that had been fed into it. He paused just long enough to study the street and pick what seemed a safe direction. Then the approaching shouts drove him on.
    In less than a minute, however, he realized this was a poor way to escape. People stared at him and he had to slow down, not merely to attract less attention but to avoid running into someone and possibly hurting him – for never, never, must a robot hurt a human being. As he turned a corner he almost ran into a policeman.
    The policeman blinked at him, astounded.
    “Now what would the likes o’ you be after in such a hurry, an’ all alone at night?”
    It was only the very special fast-thinking positronic brain that saved Sprockets now. In another second the policeman would be ordering him to halt, and of course he would have to obey. He would be questioned, and he would have to give truthful answers, for a robot cannot lie. It would all end with the policeman returning him to the robot factory where every nut, bolt, cog, and sprocket of him would be taken apart.
    Never that!
    In a flash, before the policeman’s big hand could grab him, Sprockets streaked away. At the same instant his finger reached for one of the lighted buttons in the row across his forehead. This particular button controlled his hearing antennae, which he wasn’t supposed to touch except in an emergency. Sprockets figured this was an emergency of the most desperate kind, and he was considerably relieved when his sound apparatus went completely blank. So he ran, blessedly unable to hear the policeman’s orders not to do so.
    In the next block he found a deserted alley and raced through the darkness of it for several minutes before turning on his hearing button. There was no sound of pursuit. He slowed to a walk.
    Now what should he do?
    Suddenly he stopped. Just what does a little robot do when he has managed to escape and has no place to go?
    It was a perplexing problem, and to add to his troubles was the realization that it had begun to rain. He didn’t know much about rain, but he had the vague feeling that it wasn’t at all good for his circuits.
    “To get out of the rain,” he told himself, “I will have to go where there are people. People will ask questions, then they will send me right back to the robot factory. If I want to save my cogs and sprockets, I’d better do some positive positronic cerebration.”
    Immediately he sat down in a puddle in the pouring rain and touched the middle button on his forehead. It was his cerebration button. On the instant all the buttons on his forehead began to flash in a dozen colors, and he was plunged into the deepest thought. So deep and so vast was his thinking that his brain began snapping and clicking like a runaway clock. At this moment he could have solved some of the most difficult problems in the world.
    His own problem, however, appeared to have but a single answer, and that answer seemed utterly impossible.
    “A robot,” he said in his thoughtful little voice, “cannot wander uselessly and do nothing. A robot’s purpose in life is to help human beings. Therefore I must find a human being who will not send me back to the robot factory to lose all my sprockets.”
    He thought a moment longer, and said: “In this city, according to my learning tapes, there are ten million human beings. If only one person in ten is friendly enough to accept my services and has real need of me, I must consider the other nine persons as unfriendly. It follows, therefore, that my predicament is dire, for I am alone in the midst of nine million enemies.”
    Sprockets gulped, or rather his wheels and circuits gave a loud tock that amounted to a gulp, and he wiped rain from his blinking eye lights. Abruptly, and a little stiffly, he lurched to his feet. With a hand that was not quite steady he turned off his cerebration button and clicked on his radar vision so he could see better in the black downpour. He began to walk.
    “Nine million enemies,” he repeated. “And I must evade them all until I can find a friend. I wonder why my hand trembles and my legs feel so odd. I am not exactly afraid, for a robot isn’t supposed to feel fear. Maybe it is because I am such a little robot. Or can it be the rain, and the fact that I need oiling? Maybe I’d better switch on my instinct button and see where it takes me.”
    He turned on his instinct button and moved valiantly ahead.
    The rain continued. The night grew darker. Sprockets walked bravely on, following his positronic instincts, but his feet moved slower and slower. His brain clock ticked off the minutes and hours. By the time his distance computer had registered thirty-five thousand six hundred and forty-two steps, or exactly ten miles from his cerebration point, he realized he could go no farther. Something was very wrong with him. He had been so busy evading millions of enemies and following his positronic instincts that he had been unable to search for a single friend. Nor had he but the haziest idea of his location except that he was in a parklike area of trees and shrubs exactly three hundred and twenty-one and a half degrees north of the robot factory, and that off in the trees was a big dark house where everyone was asleep except the dog. A dog was barking and coming toward him.
    Sprockets tried his best to turn and run. He could not. He felt himself slipping, his knees folding.
    He did not know that his little switch box, which was built in the middle of his back, was still exposed. Ordinarily, had he been a proper-size robot, and properly inspected, the inspector would have covered his switch box with a plate stamped with a number and all kinds of special information about voltage and oiling and the like, and what to do about dampness and short circuits and other matters that pertained to his anatomy.
    But he had no plate for protection. Now, as his knees folded, a twig from a shrub behind him caught on his exposed switch and turned him off.
    Instantly the row of lighted buttons on his forehead went out. His eyes dimmed to a very faint glow and it was impossible for him to twitch a finger. Only his positronic brain remained awake, but it might just as well have been asleep for all the good it did him.
    The rain stopped, although it mattered little to him now in his present condition.
    He sat on the wet ground in front of the shrubbery, motionless and helpless.

Chapter 2: He Is Adopted Temporarily
    Long minutes ticked away in Sprockets’ head. The dog raced around him, barking furiously. Sprockets was dimly aware of the barking dog and, finally, of two figures approaching in the night. Although his brain was awake, it wasn’t able to do much more than add long columns of large imaginary numbers, full of sevens and nines, just to keep its trillions of circuits in working order.
    Now he stopped adding numbers and tried to concentrate on the approaching figures. It was very hard with the dog barking in front of him.
    A light flashed. A man’s voice said: “Enough of that barking, Yapper! What have we here?”
    “It’s a robot!” exclaimed a boy, very much excited. “A little robot! Oh, Daddy, can I keep him? Huh, Daddy, can I?”
    “Why, bless me, it is a robot!” said the man. “And hardly as big as you.”
    “Say, I’ll bet he’s the robot that escaped from the factory. I heard about it on the radio just before I went to bed. Can I keep him, Daddy?”
    “Absolutely not,” the father said. “He doesn’t belong to us. Furthermore, if he’s an escaped robot, he’s undoubtedly aberrated and therefore dangerous. I wouldn’t dream—”
    “What’s ‘aberrated’ mean, Daddy?”
    “Cuckoo. Now hush and let me examine him. Where are you from, robot?”
    When no answer came, the man said, “I declare, I believe his switch is off.” He reached behind Sprockets, found the switch, and turned it on.
    Instantly Sprockets awakened as if from a bad dream. His eyes glowed brighter and his forehead buttons flickered with dull color. But when he made an effort to rise, his joints creaked and he could hardly move.
    “What’s your name and why did you come here?” the man asked.
    Sprockets tried to say that he didn’t have a real name, and that all his cogs and sprockets seemed to be stuck. But the only sound he was able to squeeze through his metal lips was the single word, “ – sprockets—”
    “So Sprockets is your name, eh? Well, Sprockets, you seem to be in pretty bad shape. Come, Jim, help me get him into the lab. I guess he’ll be harmless enough until I dry him off and oil him. His joints are rusting from the rain, and I imagine he’s full of short circuits.”
    After much stumbling and trouble, Sprockets was hauled into a big shop and laboratory in the rear of the house and placed on a stool beside a workbench. While Jim and Yapper, the dog, watched, Jim’s father dried him with a towel and oiled him from neck to toe.
    Jim’s father was a very tall, thin man with a thick mop of white hair, thick glasses, and a sort of perpetual frown that comes from trying to solve too many puzzles. Like Jim, he was wearing a blue bathrobe over striped pajamas. The workbench behind him was piled with all kinds of strange apparatus. The clock on the wall above it sang a little tune, and announced sweetly, “It is now four in the morning, and there are no flying saucers in sight.”
    Jim’s father scowled at the clock, then frowned at Sprockets and said: “I am Dr. Bailey. Do you understand me, Sprockets?”
    “Y-yes, sir,” Sprockets answered weakly. “Are – are y-you a medical d-doctor, sir?”
    “Absolutely not,” said Dr. Bailey. “You let me ask the questions. Did you escape from the robot factory?”
    “Y-y-yes, sir. I – I-I—”
    Dr. Bailey shook his head. “That’s too bad. It is evident by your voice and your actions that you are very, very aberrated. I’d better phone the robot factory immediately to send someone for you.”
    “Oh, n-no, sir! Please don’t!” Sprockets fell on his knees. With hands that trembled because of his damp circuits he clutched the doctor’s robe. “P-p-please don’t order me back to the factory! They’ll take me apart and I – I-I – I’ll cease to be!”
    They were interrupted by a short, plump little woman, also wearing a blue robe, who came through the shop door. She had a turned-up nose and quick birdlike blue eyes like Jim’s. When she spoke she tried to sound very fierce, but somehow she didn’t quite manage it.
    “Barnabas Bailey!” she snapped. “What on earth are you and Jim doing up at this hour? There are no flying saucers gadding about.” Then she saw Sprockets. “My goodness gracious – what is that?”
    “It’s the escaped robot, Mom,” said Jim.
    “Oh! the poor little lost frightened thing! Here, let me—”
    “Careful!” cautioned the doctor. “He’s undoubtedly aberrated. He may be dangerous.”
    “Pooh and nonsense! You’ve got him scared half to death. He’s been out in the rain all night and he’s famished for something hot in his tummy.”
    “My dear Miranda,” the doctor said patiently. “Robots do not eat.”
    “Oh, but they do, Barnabas. Robots and boys, they’re just alike. You get either of them cold and wet, and they must have something hot. For boys, it’s hot soup. For robots, it’s a hot shot.” While she spoke she was swiftly doing things with the extension cord on the workbench. She plugged the end of it into the socket in Sprockets’ switch box, touched a control on the bench, and gave a little chuckle.
    A wonderful, wonderful, warmth spread suddenly all through Sprockets, and he tingled deliciously from the tips of his toes to the ends of his positronic circuits. His eyes began to shine brightly and all his buttons flashed with brilliant colors.
    “You see, Barnabas,” said Mrs. Bailey. “You may be a towering genius in all kinds of ologies, but you don’t know about boys and robots. It takes a mother’s touch. The little dear’s atomic battery was all run down, and it hadn’t had time to recharge itself.”
    She stooped in front of Sprockets, smiling. “Now, young fellow,” she began, “tell me all about yourself.”
    Sprockets told her, gratefully. “So you see, ma’am,” he finished, “I’m not the least bit aberrated, as you can easily tell, and I escaped only because I had to.” He paused and gave her his most earnest and entreating look. “Please, ma’am, would you consider adopting me? You’ll find me a willing little fellow. I’m highly intelligent and full of capabilities.”
    “Well—”
    “Oh, Mom, please!” Jim begged. “Can’t we keep him, Mom?”
    “That’s up to your father, Jim.”
    “Absolutely not,” said the doctor. “In the first place, he doesn’t belong to us. In the second place—”
    “But, Dad, can’t we buy him?”
    “Certainly not. You know how I feel about robots.”
    “Now, Barnabas,” said Mrs. Bailey, “for a famous scientist you’re terribly old-fashioned. We could all use a smart young robot, and I’m sure Sprockets is as intelligent as he says he is. A robot cannot tell a lie.”
    “A robot,” said Dr. Bailey, frowning darkly, “is a mechanical contraption. No mechanical contraption is truly intelligent.”
    Sprockets stood up suddenly, blinking his eye lights. “But I am intelligent, sir, if you will permit me to explain. I have a genuine Asimov Positronic Brain!”
    “Eh?” The doctor stared at him. “Say that again.”
    “Yes, sir. I have a genuine Asimov Positronic Brain with twenty trillion printed circuits.” Sprockets lifted his head proudly. “I am capable of the most intense cerebration known to robotics. I never forget anything. I can learn all.”
    “All?” said Dr. Bailey, lifting his eyebrows.
    “All, sir,” answered Sprockets. “And I can draw logical conclusions.”
    “H’mp,” grunted the doctor, scowling.
    “Please, Daddy,” Jim pleaded, “won’t you buy him for Mom and me? Then he can help me with my chores, run errands for Mom, and maybe do special calculations for you. Can you calculate, Sprockets?”
    “With my brain,” Sprockets answered with dignity, “my propensity for calculation is boundless. Although I have been given only a cursory education in mathematics, I need only to be fed the proper educational tapes to become adept in advanced calculus.”
    “H’mp,” muttered the doctor, still frowning. “You have a high opinion of yourself.”
    “Oh, Daddy, please,” Jim began again. “Can’t we—”
    “Barnabas,” Mrs. Bailey said, “I have the greatest respect for you as a scientist, but you know how addled you get when you have to add and subtract fractions. You’re always having Jim do your fractions, and that isn’t right. Sprockets could handle them easily, and probably help you on your Moon research as well. Now you go right to the telephone and call the robot factory.”
    “But, Miranda, I don’t want a robot!” the doctor cried, running his fingers through his mop of thick white hair so that it stood straight up. It gave him a very wild appearance. “And why shouldn’t Jim do all my fractions? He’s nearly eight—”
    “I’m practically eleven!” Jim interrupted. “Can’t you ever remember my age?”
    “Well, h’mp, six, eight, ten, twelve – bless me, what’s the difference so long as you have a superior mentality like, h’mp, your daddy. But about the robot factory. There’s no one there I could talk to at this hour.”
    “Sir,” said Sprockets, “the sales department is always open.”
    The doctor frowned at him, then turned reluctantly to the telephone on the workbench.
    When he had the night salesman of the robot factory on the line he said: “I’m Dr. Barnabas Bailey, and I’ve found your robot that escaped. How much do you want for him?”
    He listened a moment. “What?” he cried. “That much? For a little half-grown pintsized bundle of rusty scraps? Why, bless me, he’s not even gold-plated! Huh? His brain? Yes, I realize a positronic brain is positively super, but I had no idea – H’m – Yes, I’ll think about it. Trial period, eh? Very well, I’ll try him out and let you know.”
    The doctor slammed down the receiver and glared at Sprockets.
    “You’re on probation,” he growled. “One month. I may buy you, and I may not.” Suddenly he shook his finger under Sprockets’ nose. “Now mind! For the next thirty days you’d better be on your toes and keep all your positronic circuits really clicking. Otherwise you’re going right back to the factory!”
    At that moment a red light flashed from the clock over the workbench. An alarm bell rang and the clock’s voice fairly shrieked: “Flying saucer! Flying saucer! Flying saucer!”
    The doctor raced out of the shop and went pounding through the house, with Jim and Yapper at his heels.

Chapter 3: He Becomes Partially Educated
    Sprockets blinked his eye lights at the curious clock that had caused such a commotion. Briefly he touched his cerebration button. After a moment he turned to Mrs. Bailey.
    “Flying saucers,” he said pensively. “Can you tell me, ma’am, whether the subject comes under the heading of aircraft or crockery? There’s nothing in my memory banks that serves as a clue.”
    Mrs. Bailey chuckled. “Probably space craft. They are strictly out of this world, my dear, and no one knows beans about them. Not even Barnabas.”
    “But it is obvious, ma’am, that he has a consuming interest in them. I would deduce that he has an automatic observatory connected with the clock somewhere nearby. Is that right?”
    Mrs. Bailey patted him on the head. “Your education may be limited, but your positronic circuits are clicking beautifully. Yes, Barnabas is absolutely dotty on saucers, and so is Jim. The subject comes next to his Moon research. They have an observatory in the attic, but it doesn’t work too well. It has probably spotted another shooting star.”
    She stooped, examining him with a motherly eye. “You’ll need clothes so you can have pockets. But first I’d better fix a cover for your switch box so you won’t get turned off accidentally. Barnabas should do it, but he’ll forget. His mind is on so many things. Let me see – a bit of tin and a screw should do it.”
    A switch-box cover was speedily made and fastened in place. Next came a pair of blue overalls that had been ordered for Jim, but were a size too small. They fitted Sprockets perfectly. Mrs. Bailey found a tiny wrench and a screwdriver, which she placed in one of the pockets. Into the other pockets went a small can of oil, a polishing rag, and one of Jim’s handkerchiefs.
    “Now remember,” she cautioned, “if you want the doctor to like you, you’ll have to keep your fastenings tight, and your joints oiled so they won’t squeak.”
    “Yes, ma’am.”
    “And you must stay brightly polished at all times. Don’t ever let me catch you with even one speck of dust or a spot of rust on you.”
    “Yes, ma’am. No, ma’am.”
    “It isn’t that the doctor doesn’t really like robots, but he hasn’t got used to the idea of you yet. He’s only an overgrown boy.”
    Sprockets said plaintively, “I wish I could be a real boy instead of a robot.”
    “Pooh and nonsense! Boys are always hungry or dirty or aching somewhere; they have to sleep nine hours every night, and it takes years and years to beat an education into their craniums – because their craniums are made of solid ivory instead of positronic circuits. See? You’ll never have their worries. You can learn anything in the world in practically no time by running a tape through your head.”
    “Yes, ma’am,” said Sprockets. “But it isn’t quite as easy as it sounds. An educational tape sends a hot buzzing through all my circuits. Just imagine how it is when twenty trillion circuits get buzzingly hot all at the same time.”
    “Does it make you a little feverish?”
    “Oh, ma’am, it makes me feel positively fried.”
    “Then I’d better get some ice packs ready for your head, because you’re going to start frying as soon as I can have some educational tapes delivered. You don’t want to be sent back to the factory. So if you live with Barnabas, you’ll have to be educated practically to a brown crisp and know nearly all.”
    She went to the phone and began checking off the tapes she felt were necessary.
    “First, languages. Latin, of course, and French, Spanish, German, and Greek. Barnabas will insist on Greek. Then the ologies, including extras like meteorology, craniology, minerology, cosmology – and I do think a little numerology and astrology would help us wonderfully. Then there are the onomies. Now let me see. Agronomy, astronomy, Deuteronomy – Oh, dear, I’m getting a little mixed—”
    She was still busy on the telephone, ordering enough tapes to sizzle an army of robots, when Jim and Dr. Bailey rushed back into the laboratory.
    “It was a real flying saucer!” Jim cried excitedly. “Only it was all purple – going like a purple streak—”
    “ – right overhead,” gasped the doctor. “Bright purple! Most remarkable—”
    “ – and the camera jammed and we didn’t get a picture of it. Going like a purple streak. Straight for Mexico—”
    “Straight for Mexico! Quick, Miranda,” the doctor begged. “Let me have the phone! I’ve got to call Salazar!”
    The doctor almost snatched the receiver from Mrs. Bailey’s hand. He dialed for the operator. “Long distance!” he shouted. “Hurry! This is a matter of momentous magnitude! I want to talk to Don José Salazar at the Rancho Diablo, Monteverde, Mexico.”
    Sprockets stood respectfully to one side, his little hands clasped patiently while he watched and listened. He tried to remain silent until he was needed, as a proper robot should. But finally his curiosity got the better of him.
    He turned on his whisper button and asked Jim, “Who is Don José Salazar?”
    “He’s Dad’s friend in Mexico,” Jim whispered back. “He watches for saucers too, and takes wonderful pictures in color. We’re hoping he can get a picture of this one. No one’s ever seen a purple saucer before. Imagine, bright purple! And it shimmered. It was terrific.”
    Sprockets couldn’t quite imagine it, even with his imagination button turned on, but it was evident that it must have been simply terrific, from the effect it had on everyone. When, presently, the doctor was shouting Spanish into the telephone, and Don José Salazar, far away in Mexico, was shouting Spanish back at him, even the telephone crackled with the excitement of it. A purple flying saucer!
    Long after daylight came and Sprockets had helped Mrs. Bailey serve breakfast, the feeling of excitement lingered. The doctor paced the floor, waiting for Don José to call him back and say that he had seen the saucer and managed to take pictures of it.
    The doctor was still pacing, and scowling momentarily at the telephone, when the box of educational tapes arrived from the factory. Sprockets opened the box. At the sight of so many tapes, dozens and dozens of them, he gave a loud tock and almost stopped ticking.
    Mrs. Bailey said: “There’s no use wasting time sorting them out. We’ll begin with the one on top and educate you right down to the bottom of the box.”
    “B – but, ma’am—”
    “No buts,” she said firmly, reaching for the first roll in the box. “I know it’s natural for boys and robots to balk at being educated, but that’s only because you’re ignorant. This won’t hurt a bit, and I don’t want Barnabas to send you back to the factory.”
    She inserted the end of the tape into the little slot at the back of his head, gave his learning button a deft twitch, and said: “Now there. Sit quietly, and soon you’ll be the most educated little robot on earth.”
    Sprockets did not hear her. The instant the tape began to unwind, he was oblivious to everything but the hot sizzling buzz of knowledge being crammed through his circuits. His eye lights blinked so fast that they changed color nine times a second, and a spectrum of color raced around his forehead, so that he seemed to be wearing a red, blue, and yellow halo. All his trillions of circuits clicked and snapped at once, so that the sizzling in his head was like twenty trillion fish being fried in twenty trillion skillets. When it seemed impossible for his memory banks to gulp any more knowledge, Mrs. Bailey removed the tape and slipped another on in its place.
    There was a moment of blessed blankness, then his circuits started sizzling again. He was powerless to protest or even to move a finger. Knowledge, all kinds of curious knowledge that only a human could have dreamed about, whirled through him – with every little particle of it looking for a memory cell and cramming itself into it as fast as it could. Knowledge completely over-whelmed him, and minute by minute his head seemed to grow bigger and bigger and hotter and hotter.
    And still Mrs. Bailey fed new tapes into his little slot.
    It is probably a good thing that the telephone rang when it did, for Mrs. Bailey had forgotten the ice pack. If she had fed him any more tapes when his circuits were so overheated, it is possible that poor Sprockets would have burned out all his fuses and been only a little dummy for the rest of his life.
    But Don José Salazar phoned, and the education of Sprockets was temporarily interrupted.
    When Mrs. Bailey finally turned back to Sprockets, she was amazed to see him stretched limply on the floor with his mouth wide open and his toes turned up. The glow was almost gone from his eyes, and his ticking was so faint she could hardly hear it.
    “Oh, dear! Oh, dear me!” she wailed. “I hope I haven’t killed him. Barnabas, what shall I do?”
    The doctor paid not the slightest attention to her. He was shouting to Don José on the telephone, and he was so tremendously excited that his glasses were hanging by one hook and his mop of white hair was sticking out in all directions. He had even forgotten his Spanish and was shouting in English.
    “Great guns!” he cried. “It’s down, you say? High in the mountains? Then hold everything! I’m flying out. ¡Sí! Sí! Pronto!”
    He dropped the receiver. “Miranda, quick! Pack my bag. I’m on my way to Mexico. The purple saucer had an accident. It’s down in the mountains!”
    In the confusion it was Jim who remembered to get the ice pack from the refrigerator and bring it to his mother. She placed it on Sprockets’ head, which was practically blistering.
    “Poor little darling,” she said. “You’ll cool off in a minute and feel just ducky. Would you like a hot shot to bring up your battery?”
    “No – no!” Sprockets managed to say, stirring faintly. “Nothing hot – please! O-o-oh, my sizzling circuits! I didn’t know I could know so much!”
    “Miranda!” the doctor called. “Did you hear me? I’m going to Mexico!”
    “Yes, dear, I heard you. Now you calm down, Barnabas. That purple saucer will stay where it is until you and Jim get there—”
    “It won’t stay there long – and who said Jim is going with me?”
    “You’re taking the ’copter, aren’t you, dear?”
    “Of course I’m taking the ’copter! How else would I get there in a hurry?”
    “Then naturally Jim goes with you to do your piloting. The Aeronautical Board says he’s a much better pilot than you, and they’ve given him a special license in spite of his age. I want you to get there safely. And I think it would be a good thing if you took Sprockets along to look after you both.”
    “Absolutely not!” snapped the doctor. “If you think I’m taking that half-baked little bundle of circuits—”
    “Now, Barnabas, he’s not half-baked. He’s merely half educated, and a bit overheated, but I’m sure he’s absorbed enough education to be a great help. And you really do need someone who can remember absolutely everything he sees and hears. Think how it would be if you ever got inside that purple saucer. Have you got super-super vision with a radar attachment, and positronic photographic memory?”
    “Well,” he grumbled, “since you put it that way—”
    “Then it’s settled,” she said sweetly. “Jim, you warm up the helicopter while Sprockets and I pack the bags and fry some chicken for your lunch.”

Chapter 4: He Has Trouble in Mexico
    Sprockets hadn’t quite recovered from his education when he carried the bags out to the helicopter. In spite of several ice packs, his circuits felt blistering, and a lot of his new knowledge was still buzzing back and forth as if it would strain the seams of his memory banks. Although it was wonderful to know so much, he almost wished someone would turn him off. Then he could sit down peacefully and merely add large numbers, full of sevens and nines, again. But no one thought to turn him off, nor did he dare suggest it.
    Finally they were ready to go.
    Mrs. Bailey kissed them all good-by, shedding a tear for each of them and cautioning them to beware of Mexican bandits. Jim gunned the motor, and the helicopter rose high above the Bailey courtyard.
    “It isn’t the thought of bandits that worries me,” Dr. Bailey grumbled. “It’s old Professor Katz.”
    “Daddy,” said Jim, “do you suppose Professor Katz saw that saucer?”
    “Jim, if we saw a purple saucer, you can bet all your uncut wisdom teeth that Prof. Vladimir Katz saw a purple saucer too. He never misses anything, except a trip to jail.”
    Sprockets was beginning to feel better in the cool upper air. “May I be permitted to ask, sir, who is Prof. Vladimir Katz?”
    “He is a thorn in my side,” growled the doctor. “He is an offense in the eyes of science. He steals inventions. He steals ideas. He steals credit for other men’s work. If he can get to Mexico first, you can bet your last cog and sprocket he’ll steal that purple saucer – and sell it to the Russians.”
    “Then I regret to inform you, sir, that matters are very bad indeed. We should not be traveling at this time. The stars are against us, sir.”
    “Eh?” said the doctor. “What’s this? Stars, did you say?”
    “Yes, sir,” Sprockets replied solemnly. “They are definitely incompatibly inauspicious.”
    Jim said, “What’s ‘incompatibly inauspicious’ mean?”
    “Blessed if I’m sure,” muttered the doctor, “but we’ll both find out if you hit that thundercloud. Watch your piloting! Sprockets, how do you know that the stars are inauspicious?”
    “Sir, my last learning tape, before my circuits became overheated, dealt with astrology. It was most enlightening, even though my circuits are still buzzing from it. You see, sir, Mars and Saturn are in conjunction, Taurus is in the ascendancy, and the Moon—”
    “Drivel,” muttered the doctor. “Pure incompatible, inauspicious drivel. I hope and pray you learned something really useful, like Spanish.”
    Sprockets swallowed – or rather he gave a little tock that amounted to a swallow. He was trying so hard to please Dr. Bailey, but the doctor was evidently a very difficult man to please.
    “I – I’m terribly sorry, sir,” he said in a small voice, “but I did not progress so far as the Spanish tape. I had time only for French, German, Sanskrit, and Zapotecan.”
    “That does it!” exploded the doctor. “What earthly good will you be in Mexico if you can’t speak Spanish? I should have had my head examined before I ever let Miranda put you aboard!”
    “Sir—”
    “Quiet!” snapped the doctor. “Or I’ll turn you off! Jim, can’t you get more speed out of this helicopter?”
    “I can fold the rotors and use the jets. But, Dad, I’d rather save the jet fuel for an emergency.”
    “This is an emergency,” the doctor said sharply. “If we don’t get to that saucer ahead of Professor Katz, he’ll steal everything in it for the Russians – or whoever it is he steals for – and science will be the loser.”
    “Sir,” Sprockets began again, “with Mars and Saturn in conjunction, I implore you—”
    “I don’t want to hear about Mars and Saturn!” cried the doctor. “All I want is to find that purple saucer. I told you to be quiet, or I’ll turn you off!”
    “But, sir—”
    CLICK!
    Sprockets froze, with his mouth wide open. He no longer ticked. The doctor had turned him off. Only his positronic brain continued to work, and this time he was too upset to add numbers.
    Of course, he knew he shouldn’t have tried to talk when he had been ordered not to. But he’d only been doing his best to help the doctor. A robot has to help his master even if it means disobeying an order. According to his learning tapes – and those included several ologies as well as an onomy – this was a very, very, bad time to travel, especially in the air.
    Astrology said it was inauspicious.
    Numerology said their numbers were all at odds and that they had only one chance in nine.
    Meterology said the weather was going to be foul, with isobars and isotherms all tangled up with rain, sleet, snow, and hail, as well as thunder and lightning.
    Astronomy said the sun was full of spots, a most serious matter, which affected practically all the onomies and ologies.
    But when you’re a turned-off robot, unable to tick a tock or budge a sprocket, and small in the bargain, all you can do is sit and worry. So Sprockets sat and worried while Jim folded the rotors and turned on the jets. The helicopter – which was no longer a helicopter but the next thing to a comet – streaked cometlike for Mexico.
    They reached the border in practically no time. There was a fretting delay while Jim used the rotors to come down and be checked through by the border guards. There was even more delay on the other side of the border when Mexican customs officials pried through the bags and made a great fuss about Sprockets. The air rattled with their incomprehensible Spanish, and the doctor rattled back at them.
    Finally they were allowed to proceed. Again Jim folded the rotors and used the jets. In less than a tick they were streaking over the Mexican mountains. In slightly more than a tick they were darting through thunderclouds and trying to dodge lightning. Then hail was pelting the cabin like buckshot, snow was blinding the windshield, and suddenly it was raining rivers where it had never rained before.
    “Great jumping jiggling jeepers!” cried the doctor. “What could have happened to have caused all this?”
    Sprockets tried to say sunspots, but he was still turned off and all he could do was hope. There came a blinding flash of lightning, then it turned black as night and the helicopter began to fall, spinning and twisting. The jets had failed.
    Somehow Jim got the rotors unfolded, and barely in time. The rotors broke their fall, but only enough to save them from being killed as the helicopter crashed.
    The helicopter was a complete loss. Jim had a scratch or two; Sprockets was aware of a dent in his leg, which he was afraid would make him squeak when he tried to walk; but the doctor had nothing wrong with him save his temper.
    For a while all the doctor could mutter was, “Blankety, blankety, blankety!” Then he managed to say fumingly, “If it wasn’t for that blankety little robot, we wouldn’t be in this blankety big trouble.”
    “Aw, now, Dad,” said Jim. “It wasn’t Sprockets’ fault.”
    “It was his blankety fault for being along!” sputtered the doctor. “He jinxed everything!”
    “But, Daddy, I didn’t know scientists believed in jinxes.”
    “We don’t,” fumed the doctor. “But look what’s happened! Where are we?”
    “I don’t know, Daddy. Maybe Sprockets can tell us. Shall we turn him on?”
    “You turn him on. I absolutely refuse to touch him.”
    CLICK!
    Sprockets came to life again as Jim turned his switch.
    “Where are we, Sprockets?” Jim asked.
    “One moment, please,” said Sprockets, blinking his eye lights and reaching for his cerebration button.
    The storm had passed. The evening sun was out, shining brightly. Around them great mountains rose, brown and jagged and spattered with green cactus.
    “According to my calculations,” Sprockets began, “we are one thousand, seven hundred and seventy-seven and approximately one-twelfth miles from home.”
    “And where does that put us?” growled the doctor.
    “North-northwest and a fraction north of Monteverde and the Rancho Diablo. The latter, sir, is three miles and a few yards down the valley.”
    “H’mp,” grunted the doctor, somewhat mollified. “H’mp. Then get our bags and let’s start walking.”
    They began walking toward the Rancho Diablo. Sprockets trotted behind, carrying their bags and squeaking with every step because of his dented leg. Twice he stopped to oil it, but still it squeaked. He felt very much ashamed, and unwanted besides. Maybe he had jinxed the trip by trying so hard to please the doctor. Now they had lost the helicopter, and instead of being able to fly to the purple saucer, they would have to climb through the mountains on foot.
    As they neared the big adobe ranch house, Don José Salazar saw them coming, and leaped upon his horse and galloped to meet them. He was a huge man with big sweeping mustachios, big limpid black eyes, a pair of very big pearl-handled pistols in his belt, and a pair of very expensive cameras slung over his shoulders.
    “Barnabas!” he roared in English. “Welcome! What happened? Where is the helicopter?”
    “Wrecked, José,” the doctor said grimly. “How far away is the saucer?”
    “Without the helicopter, we must journey maybe a night and a day. And we must start at once, pronto. Our luck, she is very bad! That no good hombre—”
    “Professor Katz?”
    “Sí, sí! That no-good Prof. Vladimir Katz! He is in Mexico. My scouts, they see him. He is climbing the mountain this moment to find that saucer. Come queek! There is no time to waste! I am all ready to go with pistols and cameras loaded.”

Chapter 5: He Meets Professor Katz
    There was no time at all to waste if they would reach the purple saucer before Prof. Vladimir Katz got to it. According to Don José’s scouts, the purple saucer had fallen somewhere in a high valley in the mountains beyond the ranch. Prof. Vladimir Katz and his men had been seen struggling up a narrow mountain trail only an hour ago.
    “But I know a shorter trail,” said Don José. “We will take horses and get ahead of them to the high pass. Then we will leave the horses and go on the feet. The way, she is very deeficult.”
    Don José bellowed orders. Men ran. Horses were brought and saddled, and saddlebags packed.
    Sprockets tried valiantly to mount one of the horses, but even with Jim helping, he simply could not manage it.
    “The leetle mechanical one,” said Don José, “ha, he is not built right for the horse.”
    “Then we’d better leave him behind,” said the doctor. “We’ve had enough headaches with him already.”
    “Oh, please, Dad,” Jim begged. “There must be some way he can go. We’ll need Sprockets.”
    “Ah, maybe he fit the burro,” said Don José.
    A little burro was quickly brought and saddled. Now Sprockets had no difficulty, for he fitted the burro perfectly. However, he had to turn on his balance button so he would not fall off.
    They started away at a fast gallop for the distant trail, Don José Salazar leading with cameras and knapsack flopping over his shoulders. Behind him came Dr. Bailey, Jim, and two of Don José’s scouts, who looked like Mexican bandits – which they probably were when they were not scouting.
    Far behind them all rode Sprockets on the burro. Try as he would, the little burro could not keep up with the galloping horses. Minute by minute the horses got farther and farther ahead, till at last they vanished in the distance.
    Sprockets was not worried. Easily he followed their hoofprints until dark. Then he turned on his radar vision and rode bravely on through the night. But up on the wild slope of the mountain, with huge rocks as big as houses everywhere around him, his radar vision did not help at all. He tried his night vision button, but that did not help either, because the horses’ hoofs had left no print on the hard rocks. So there was nothing he could do but make use of the very special button that controlled his ultraviolet perceptors.
    Now, his ultraviolet perceptor button was so very special that Sprockets was not supposed to touch it except in an ultraspecial emergency, and then for only a few seconds at a time. He did not know exactly what would happen, but he resolved to take no chances. He stopped the burro, clung tightly to the saddle with one hand, and quickly turned on the button with the other.
    Instantly he shone all over with a strange violet fire. Violet fires danced about his head and shot in blazing streaks from his eyes. He looked so much like a hot hobgoblin that the sight of him frightened a curious mountain lion almost out of its wits. Even the patient little burro was frightened for a moment, and Sprockets might have been thrown from the saddle if he hadn’t been clinging tightly and had his balance button on.
    “Wow!” Sprockets said fervently. “I didn’t know I had that in me!”
    Hurriedly he turned off the button that had caused such a commotion, and rode on, using only his night vision. His ultraviolet perceptors were so strong that they had showed him every hoofprint on the bare rock for as far as he could make out the trail, which he memorized instantly. It was midnight when he reached the spot where Don José Salazar and his party had left the horses and gone ahead on foot.
    Sprockets tied his burro to a bush near the horses, oiled his squeaky leg, and patiently began climbing through the narrow pass.
    With his balance button turned on, he was able to climb very easily, though squeakily, over places where ordinary humans had to pant and groan and spend much of their time resting. It is not surprising, therefore, that he caught up with the others just as the Moon came up over the mountain peaks. The Moon, which had been rising on the other side of the mountains, now shone upon them, round and full and bright.
    Jim and Dr. Bailey were so tired they could hardly groan. Don José Salazar was too angry to be tired. He had lost his pearl-handled pistols in a deep ravine. He had lost both his scouts, whom he suspected of being bandits. He had lost one of his precious cameras, and finally he had lost his way in the darkness.
    Now he was in the middle of losing his temper.
    “Peegs!” he roared. “Peegs and worms! Peegs, worms, and bandits!” He paused and then shouted, “If I ever catch those unspeakable, unmentionable, unhallowed, unholy, unnecessary, un – un – un—”
    “Sir,” said Sprockets. “Are you referring to your lost scouts?”
    “Shut up!” roared Don José. “Let me be unhappy in peace!”
    “Sir,” Sprockets pleaded. “I beg you to be unhappy quietly, or you will be heard.”
    “I want them to hear me!” Don José shouted. “What’s happened to the rascals?”
    “Sir,” said Sprockets. “They have been captured by Prof. Vladimir Katz and his men.”
    Dr. Bailey sat up. “Nonsense!” he said. “Utter, complete, positronic nonsense!”
    “Reedeeculous!” said Don José. “That Vladimir Katz, he is miles behind us on the other trail!”
    “Sirs,” said Sprockets, “I regret to inform you otherwise, but he is ahead of us. I can hear him with my superaudio hearing. By the sound, he is only seven hundred and sixty-nine feet away. He has captured your scouts, Don José, and now he is ordering his men to come and capture us.”
    “There’s something fishy about this,” said Dr. Bailey. “Sprockets, how can you understand what he’s saying to his men if you don’t know Spanish?”
    “Sir, he is not speaking Spanish. He grunts in low German when he speaks unspeakably, but he talks to his men in Zapotecan, with which I am familiar. I would deduce, sir, that his men are renegade Zapotec Indians.”
    “Well, bless me!” said the doctor. “Bless me!”
    “Sir,” Sprockets continued hastily. “I would suggest that we hide quickly, for they will soon be here. We have no weapons, and I believe they are armed to the teeth. They sound very bloodthirsty. There is some mention of slicing us in little pieces and feeding us to the mountain lions.”
    There was no time to search for a good hiding place. They crouched in the black shadows behind the rocks on the side of the trail. Now the only sounds in the stillness were the occasional rattling of falling pebbles, and a distinct ticking that came from Sprockets.
    “We’d better turn him off,” whispered the doctor. “They are bound to hear him tick, and he squeaks every time he moves.”
    “Oh, please—” Sprockets began, but that was as far as he got.
    CLICK!
    He was turned off. It was the last thing Sprockets wanted, for he had a plan – a beautiful plan – that would have saved them all. But now he couldn’t use it. He was helpless.
    The next few minutes were the worst Sprockets could remember in all his short life. He couldn’t turn his head or actually see anything, but he was vaguely aware of movement, of fierce Zapotec Indians armed with long, sharp machetes creeping stealthily down the trail toward them.
    The Zapotecs reached the rock where Sprockets was hiding. They stopped. There were hurried whispers among them. Then a guttural voice gave an order. The Indians moved soundlessly on.
    A minute passed. A cloud drifted over the Moon, and suddenly it was dark again on the mountain.
    Dr. Bailey whispered: “Here’s our chance! Let’s get away from here!”
    The doctor touched Sprockets’ switch that clicked him on, and started to leave. But Sprockets stopped him.
    “Wait!” he whispered. “They are coming back! Please don’t turn me off again. I have a plan.”
    Before the doctor could protest, Sprockets darted squeaking down the trail toward the approaching Indians.
    When he was a few yards away from them he paused, adjusted his voice button in a way he hoped would be proper for the occasion, then instantly turned on his ultraviolet perceptors.
    Again he glowed like a hot hobgoblin. Violet fires circled his head and shot in blazing streaks from his eyes. He raised his arm and pointed a fiery finger at the approaching Indians and Prof. Vladimir Katz.
    In a hollow voice – as dreadfully hollow as his button would allow in Zapotecan – Sprockets said: “Flee to your homes, Zapotecs! Flee for your lives! Have nothing to do with Vladimir Katz. He is a man of evil.”
    Five fierce Indians stopped in their tracks. They stared at him, utterly astounded. Their mouths dropped open, and their gleaming machetes dropped from their hands. Abruptly, without a sound, all five of them whirled and fled, leaping like mountain goats to get away from this fiery horror with the pointing finger.
    Only Prof. Vladimir Katz stood his ground. Or rather, he tried to stand his ground. He was a fuming, wheezing, waddling barrel of a man with no hair on his head, no neck under it, and a great many chins – possibly four or five. Being very learned in several ologies, he should have known better than to think of trying to stop five fierce Zapotecs with a sudden urge to go home. So, naturally, he was knocked sprawling, and might have rolled off the mountain if Don José Salazar had not pounced upon him and sat upon him hard.
    “Scoundrel!” roared Don José. “Peeg! Trespasser! Stealer of purple saucers—”
    “Let me go!” Professor Katz tried to roar back, though he could only wheeze. “I am a friend of the governor of Monteverde. When I tell him of this outrage—”
    “Fool!” said Don José, “I am the governor of Monteverde. You are in this country without the permit. For a brass peso I would have you put in the jail for life. Instead I will only fine you till your purse she is very thin. Then I will deport you to the worst place I can think of – if I can think of a worse place than Vladivostok or Sputnik-sky, which may take me years and years.”

Chapter 6: He Finds the Saucer
    Sprockets was so tired when it was all over – or rather, his little atomic battery was so run down – that his eye lights practically went out, and all of a sudden he collapsed in the trail with a loud squeak and a tock.
    Jim rushed over to him. “Are – are you sick or something, Sprockets?”
    “I am deplorably depleted,” Sprockets answered in a very weak voice.
    “What’s ‘deplorably depleted’ mean?”
    Sprockets was always surprised that Jim, who was so smart, had trouble with so many words. “It’s my battery,” he answered faintly. “It’s dreadfully low from using my ultraviolet perceptors.”
    “If only we were home,” said Jim, “Mom could give you another hot shot.”
    “That would be wonderful,” Sprockets whispered, tingling at the thought. “But I will fully recharge myself if I lie here six hours, fifty-seven minutes, and twelve seconds. Please let nothing disturb me.”
    “Just one question,” Don José interrupted, his mustachios quivering in his eagerness. “Has the leetle mechanical one any way of knowing where the purple saucer is?”
    Even Professor Katz, securely bound, and just as securely gagged – so no one would have to listen to him speak unspeakably in low German – pricked up his thick ears at the question.
    Sprockets said, so faintly he could barely be heard, “Yes – I – will – tell – you – when – I – am – recharged—”
    While Sprockets was recharging, Jim built a campfire, and Dr. Bailey and Don José went up the trail and found the captured scouts, who had been tightly bound and gagged by Professor Katz’s Zapotecs. Then everyone slept till dawn.
    When daylight came they all had breakfast, and Don José sent the scouts back to Monteverde with Professor Katz, with orders to lock the professor in the Monteverde jail.
    Now they all stood around Sprockets, looking at their watches and waiting until the recharging period was up.
    “Six seconds to go,” Dr. Bailey said finally. “Five – four – three – two – one – Ah, bless me!”
    Sprockets sat up suddenly, blinking his eye lights happily.
    “The saucer,” Don José prompted.
    “Yes, sir,” Sprockets replied. “One minute, please.”
    He stood up straight and adjusted his cerebration button. Then he touched both his instinct and his special perceptor buttons. A halo of color began flashing merrily around his head. So finely attuned was he at this moment that he could have located practically anything anywhere, including all the lost umbrellas that the Bailey family had misplaced during the last seven years.
    He began turning slowly. When he became aware of a faint, distant, and very unworldly hum – the sort of hum that couldn’t have come from anything but a flying saucer – he stopped and pointed.
    “It is less than five miles to the southwest,” he announced, shutting off his three buttons so he wouldn’t drain his battery. “I am calculating the distance in a straight line.”
    We’d better start hiking,” said the doctor. “Five miles in this country is nearer twenty on foot.”
    “And I believe, sir,” Sprockets added, “that we had better hurry. By the sound of it, I would deduce that there is nothing wrong with the saucer’s motor. I would further deduce that they have been recharging. You see, sir, my positronic inductors are responding to unusual radioactivity, and it seems evident—”
    “Save it!” snapped the doctor. “Get going!”
    There was a scramble to pack blanket rolls and knapsacks, and when they started down the farther side of the mountain, Sprockets led the way.
    They went up and down, down and up, around and across, over and under, up and down again, and in every direction except straight ahead as one does in level country. They slid, crawled, stumbled, and climbed, dropped and climbed again, and all except Sprockets panted, groaned, grunted, and often said “Ouch!” or “Oh, my poor feet!” or used other words that should not be mentioned. Sprockets only ticked and squeaked, though occasionally he tocked when the trail was dangerous.
    Finally they crawled over some boulders and slid down into a little open valley. Ahead of them something – a bright purple something – pulsed and glimmered and hummed faintly.
    It was the purple saucer, and it looked just like a flying saucer is supposed to look, except for its color. There seemed to be nothing wrong with it; in fact, it floated, motionless, a few feet above the ground.
    They stopped, breathless, and stared at it. Dr. Bailey’s mop of white hair stood straight up. Don José Salazar was so surprised that he dropped his precious remaining camera.
    Jim whispered: “A flying saucer! The real thing!”
    Don José Salazar whispered, “Except that it is very purple!”
    Dr. Bailey whispered: “Bless me! Incredibly purple!”
    Jim whispered again, “D’you suppose it has purple people in it?”
    “I declare,” said the doctor. “I never thought of that. It is a distinct possibility. But let us pray that it has purple people of some kind in it – not purple things. I wouldn’t care to meet any kind of thing in this remote spot.”
    Sprockets said, “Sir, shall I go forward and announce myself, and request permission to enter?”
    “Why, yes,” said the doctor, nodding vigorously but not stirring an inch from where he stood. “By all means, Sprockets. Go right ahead.”
    Sprockets marched bravely forward until he was within ten feet of the saucer. There he paused, raised his hand by way of greeting, and said in a dignified little voice: “I am Sprockets, a small robot of this planet. I request permission to come aboard and meet you.”
    For a few seconds nothing happened. Then there was a slight change in the saucer’s color. A touch of silver brightened the purple. There was no sign of an opening anywhere on the saucer, but suddenly an opening appeared – underneath. A slender stairway slid down to the ground. With it came curious sounds that seemed almost like music.
    Sprockets touched his cerebration button, and decided that the stairway and the musical sounds were an invitation to enter. Confidently, he marched up the stairway.
    Nothing in his intense but short education had prepared Sprockets for what he found now. His eye lights blinked twice as rapidly as usual. Though the saucer had seemed without windows from the outside, so that it was impossible to see in, it was exactly the other way on the inside. The wall all around the bowl of the saucer was transparent on the inside, and Sprockets could see everything on the outside. Through the transparent walls he caught a glimpse of Jim and the doctor, waiting expectantly in the distance, and Don José working frantically with his camera. Then all his attention went to the two beings at the head of the stairway.
    At first he couldn’t quite make them out. Their outlines seemed a little fuzzy in the purplish light. But when he adjusted his vision button, he saw them clearly.
    They were people. And they were purple. Well, not really purple, but there was a touch of color about them and their strange clothing that was like purple. They were small, hardly taller than Jim, and very, very slender and beautiful, so that they reminded Sprockets of the slender-stemmed flowers that grew in Mrs. Bailey’s garden. But they were real – though quite unearthly – people.
    Sprockets put on his best manners and gave them a polite little bow. “I am a small robot belonging to Dr. Bailey. My name is Sprockets.” He touched himself and repeated his name. “Thank you for allowing me to enter.”
    Each of the purple beings gave him a polite bow in return. From the lips of the taller one came a quick singing sound, almost like music. It was followed by what seemed to be a name, for the speaker touched his chest and sang the word several times.
    Sprockets was unable to make it out until he had adjusted his hearing button. Then he said, “Ilium?” – which was the way it sounded to him.
    The speaker smiled. “Ilium,” he said again, then touched Sprockets and added, “Sssprockeetsss.”
    The other being touched her chest, smiled, and said, “Leli.” Then she touched Sprockets gaily, and spoke singingly, “Sssprockeetsss.”
    Sprockets gave another polite little bow and actually managed to twist his small mouth into what was almost a happy smile, which is quite remarkable for a young robot made as he was, practically from scraps.
    “Ilium and Leli,” he said, “it is a great pleasure. May I invite the others aboard? They are very anxious to meet you.” And he pointed to where Dr. Bailey, Jim, and Don José were waiting.
    Ilium smiled, pointed, and beckoned with his slender hand. It was an invitation, and Sprockets wasted no time in trotting down the stairway and calling to Dr. Bailey that it was safe to enter the saucer.
    Dr. Bailey, Jim, and Don José came slowly, wonderingly, aboard. Jim’s eyes were almost as round as Sprockets’, and he gave a gasping whisper. “They are purple people!”
    The doctor whispered, “Hush, mind your manners!” Though he couldn’t help but add: “Incredibly, wonderfully purple! They must be from a purple planet!”
    Don José, his mustachios trembling, said: “Such beeautiful peoples! They will make such beeautiful peectures!” And he gave them a courtly bow as Sprockets performed the introductions, and immediately began fussing with his camera.
    “Ilium and Leli,” said Sprockets, “I want you to meet Don José Salazar, Dr. Barnabas Bailey, and Dr. Bailey’s son, Jim Bailey.”
    When they had met, the doctor turned to Sprockets, quite baffled. “Bless me, how did you learn their names? I hear nothing but a sort of rapid music when they speak.”
    “I had to adjust my superaudios most carefully, sir. But we are faced with a very serious and baffling problem in linguistics.”
    “Insuperable and insurmountable,” muttered the doctor, running his fingers through his hair so that it stood out in all directions.
    Jim said, “What’s ‘insuperable and insurmountable’ linguistics?”
    “We can’t talk their lingo,” growled the doctor. “Now hush and let me think.”
    “I’ll bet Sprockets can solve it,” Jim suggested.
    “This is no job for a half-educated bundle of circuits,” muttered the doctor, “even though they are positronic. What we need is a cross between a mockingbird and a Beethoven. Don’t you realize they speak music? Pure music?”
    “Sir,” Sprockets began, adjusting his cerebration button.
    “Don’t interrupt my thinking,” ordered the doctor, “or I’ll be forced to turn you off.”
    Sprockets closed his mouth, but he was thinking faster than he had ever thought in his life. All at once he knew he had the answer if only he were allowed to tell it.
    Suddenly he touched his whisper button and swung to Jim. Into Jim’s ear he hurriedly, quietly, poured his idea.
    Jim’s eyes widened. “Sure!” he said. “Why not? Hey, Daddy! Sprockets has a real idea!”
    “Hush,” said the doctor absently, tugging at his hair as if he would somehow loosen an idea of his own. “How many times have I told you not to interrupt me when I am concerned with a deep problem?”
    “Aw, Dad,” Jim persisted, “all we have to do is get it across to Ilium to fix up a language tape and run it through Sprockets’ head. Then he can act as interpreter.”
    “Hey?” muttered the doctor. “What’s this?”
    “A language tape,” said Jim. “From Ilium.”
    “Why, bless me!” said the doctor. “The very thing I was almost thinking of! Let’s get busy!”

Chapter 7: He Goes Space Traveling
    It really took some doing. And the doing was practically miraculous, everything considered.
    If Ilium and Leli hadn’t been such exceptional people – far, far ahead of plain ordinary Earth people – it would have been impossible. But they were so bright they positively shone when they thought. And when they thought hard, they pulsed and glowed so beautifully in a variety of colors it was almost as if they had lamps inside them. In fact, they changed so fast from purple to pink to violet, and then to mauve and back to pink, that their outlines grew fuzzy and it was actually difficult to see them.
    Just getting the idea over to them was the least of it. All Dr. Bailey had to do was show them the learning slot in the back of Sprockets’ head, then make signs of feeding an educational tape into the slot while Don José Salazar – who had a fine baritone voice – hummed a little tune. Ilium and Leli understood instantly. They needed only to give Sprockets a tape of their musical language, and the problem would be solved.
    Naturally, being from a distant planet where everything was entirely different, they had no tapes aboard that would fit a small robot on Earth. But that didn’t stop them. They darted all about the saucer, singing so rapidly to each other that ordinary ears couldn’t possibly have made out the sounds. Their slender little hands moved so swiftly from one curious machine to another that even Sprockets, with his faster than human vision, had difficulty seeing what they were doing.
    In almost no time (though to be exact it was six hundred and thirty-nine and seven tenths seconds by Sprockets’ counting) they had a special musical tape all ready for him.
    In three more seconds he was sitting glassy-eyed in the middle of the saucer with his learning button turned on, and a whole galaxy of strange music was flooding his positronic circuits.
    It was wonderful. It was beautiful. It was, of course, quite out of this world. It was not like anything Sprockets could have imagined, even with his imagination button turned on high. But it was so curious, so intricate, and it came so fast and there was so much of it, that Sprockets could feel his circuits getting dangerously hot again.
    Long before he was through his circuits were sizzling, and he had lost all accounting of time. Then came a blank interval when he was quite overcome with music.
    When he awoke he was lying flat on the saucer’s floor.
    Don José was holding his head and saying: “Ah, the poor leetle mechanical one! Pray that he lives!”
    Dr. Bailey was fanning him and saying: “Bless me, I believe he’s coming out of it.”
    Jim was bathing his hot forehead with a wet handkerchief and saying: “Come on, Sprockets! We can’t do a thing without you!”
    And both Ilium and Leli were singing sweetly to him – and he could understand them.
    Ilium was saying: “You were never in any danger, Sprockets. We knew exactly how much your circuits could take.”
    And Leli was saying, “Do you like the language of the Purple Planet, Sprockets?”
    Sprockets sat up, blinking his eye lights. In a tinny little voice he sang in reply: “It is a fascinating language, Leli. I wish I could teach it to Jim and the doctor, but I fear it is impossible. The Earth tongue is too slow, and they haven’t got positronic circuits.”
    Jim said, in English, “Why, Sprockets, you’re twittering like a bird!”
    “Really?” said Sprockets. “I feel like a bird – maybe a firebird or a phoenix. Oh, my hot head!”
    “Sprockets,” ordered the doctor, “ask them where they are from, and why they are here.”
    “Yes, sir, but first allow me to oil my tongue, sir. Theirs is a very difficult language, and quite hard on my tongue bearings.”
    Sprockets oiled his tongue, asked the doctor’s question, then gave the translation.
    “Sir, they are from the Purple Planet, which orbits around the Purple Star on the other side of our galaxy. There are three planets that orbit this unusual star. The first is the Purple Planet, where only children live. The second is the Blue Planet, where grownups live. The third—”
    “Great jiggling jeepers!” interrupted the doctor. “Do you mean to tell me that Ilium and Leli are just children?”
    “Yes, sir. They are barely a hundred years old, and are classed as young children. When they reach five hundred, and have completed their education, their inner glow will change slightly. Then they will be adults, with adult thoughts, and move to the Blue Planet. On the third planet, which is green—”
    “Incredible!” muttered the doctor. “Inconceivably, incommensurately incredible!”
    “What’s ‘inconceivably, incommensurately incredible’ mean?” asked Jim.
    “Super, super,” said the doctor. “You can’t believe it, but you do.”
    Don José said eagerly: “Proceed, leetle one. What of the Green Planet?”
    “Oh, sir, that is the most interesting one of all. It is inhabited only by the robots who make everything for the Purple and Blue People. They are terrifically smart robots who make all the flying saucers and the atomic transmuters—”
    “Atomic transmuters?” said the doctor, his hair suddenly standing straight up with surprise. “How do they work?”
    “Leli will show you,” said Sprockets. “They are simple little gadgets. Suppose you are hungry. All you have to do is put a pebble or something, to furnish the atoms, into the slot. Then you give it a taste of what you want, and press the button.”
    “Say,” said Jim, “I’m starved, and all I’ve got left from Mom’s lunch is a piece of chocolate cake I’ve been saving. Do you think—”
    “Of course,” Sprockets told him.
    He took the slice of cake from Jim’s knapsack and gave it to Leli. She slipped it into one side of the atomic transmuter, dropped a pebble into the other side, and touched a button.
    Almost instantly, six pieces of chocolate cake covered with luscious icing popped out upon the transmuter’s tray.
    “Wow!” Jim pounced upon the cake. He stuffed one piece into his mouth and passed the other pieces around. “I wish I had saved some of Mom’s fried chicken!”
    “Why, bless me,” said the doctor, “I saved a drumstick.”
    In less time than it takes to tell it, the transmuter had produced more chicken drumsticks than they could eat, but of course they ate them all because Jim was six times as hungry as the others.
    “Now,” said the doctor, when they had finished, “all this has been delightfully enlightening, but tantalizingly inconclusive.”
    “What’s tanta—” Jim began.
    “Quiet!” snapped the doctor. “Science comes first. I’ll not be interrupted by trivialities. Sprockets, find out why Ilium and Leli are here.”
    “This is part of their education, sir,” Sprockets told him after he had had a twittering and singing session with Ilium. “They visit lots of planets just to observe. They were on their way to the Moon to search for quantic moonstones when—”
    “Hey? The Moon? Quantic moonstones?” The doctor’s voice fairly vibrated, he was so interested, because the Moon was his greatest hobby, even greater than flying saucers.
    “Yes, sir. Quantic moonstones from the dark side of the Moon. They shine with a purple light, just like the Purple People, and have marvelous curative powers. They can cure purple dimness in a wink.”
    “Bless me!” said the doctor. “But continue.”
    “Yes, sir. It seems, sir, that they were approaching the Moon when there was a leakage in their hyper-sub-medio space inductors. They fixed it quickly enough, but they were almost out of power. So they came here to recharge. They barely made it.”
    “But why here?” asked the doctor. “In Mexico?”
    “Because, sir, in this particular spot, there is a great deal of radioactivity, as I tried to tell you earlier. And it is on a direct line with the Earth’s magnetic force. The two forces make it a simple matter to recharge through their hyper-sub-medio space inductors.”
    “Oh, yes,” said the doctor. “Very simple indeed. And they are going on to the Moon from here?”
    “Yes, sir,” Sprockets told him. Nor did he have to ask what the doctor was thinking. The doctor, he could tell, was fairly quivering with suppressed eagerness.
    “Sprockets,” said the doctor. “Er, would you, ah – well, what I’m trying to say is—”
    “Yes, sir,” Sprockets answered. “I understand, sir. Leave it to me, sir.”
    He turned to Ilium and sang: “Dr. Barnabas Bailey is one of the greatest scientists of our planet, but he has never visited the Moon. Would it be possible—”
    “We would be delighted,” Ilium hastened to sing in reply. “It would be a purplely glowing pleasure to take all of you to the Moon.”
    “I am told,” said Sprockets, “that it is airless, and dismally cold on the dark side. I would not mind it myself, being only a little robot. But humans would have to have space suits and special atomic lights.”
    “We can furnish those,” Ilium sang back. “Only our space suits are not regular space suits, as your people think of them. We have something much better. They are force globes. You will have to wear one yourself, otherwise you will get Moon dust in your joints, and be in an unpurplish pickle.”
    “Thank you most spectrumly,” said Sprockets, in the polite manner of the Purple People. “I expect you should have some special violet smelling salts handy when I tell Dr. Bailey you will take us to the Moon, for he will be quite overcome.”
    Sprockets was wrong. The doctor was only half overcome, for he was so eager he did not want to miss a thing. But Don José Salazar, who was five times as excitable, was quite overcome and had to be revived with the special violet smelling salts. Jim was too young to be overcome, but he danced all over the saucer.
    By the time Don José was revived, and he and the doctor were beginning to burble with pleasure at the thought of visiting the dark side of the Moon (where not even a space chimpanzee had been), the purple saucer was ninety-seven miles, six hundred and fifty-two feet, and three and three quarters inches above the earth.
    Don José and the doctor looked out, gasped, and the doctor exclaimed: “Bless me, what a sight! What a tantalizing, titillating, terrigenous humdinger of a sight!”
    And before Jim could ask what he meant, or Don José could use his camera, he hastily added: “But we can’t go to the Moon until I’ve seen Miranda. She’ll be terrible worried, and there are some things I simply must get.”
    So it was arranged for the flying saucer to drop down quietly into the Bailey courtyard, which it did.
    It landed just at dusk, which is an excellent time for a flying saucer to land, because anyone seeing it would confuse it with the sunset colors and simply wouldn’t believe it.
    Mrs. Bailey was watching for the helicopter to return. When the saucer landed, and Dr. Bailey stepped out of it, she almost had a tantrum.
    “Barnabas Bailey!” she exclaimed. “What’s got into you? Gadding around willy-nilly in flying saucers! What’s happened? Where’s the ’copter?”
    Dr. Bailey told her.
    “Now, my dear,” he went on, “you mustn’t worry. We’re just going to the Moon—”
    “The Moon!” Mrs. Bailey gasped.
    “Yes, my dear. You are invited too.”
    “Goodness gracious, no! I wouldn’t dream of it. Don’t tell me you are actually considering going there with Jim and Sprockets!”
    “Why, yes, Miranda. Now, you mustn’t worry at all. We’ll pop over, look around a bit, and pop right back.” He snapped his fingers. “Just like that. Nothing at all to it. Not in a purple saucer. They’re absolutely, positively, incontrovertibly—”
    “Oh, dear.” Mrs. Bailey fought back a tear. “I suppose they are – but all the way to the Moon!”
    “Now, Miranda, we’ll be back in a jiffy. Fix us a bit of lunch so we won’t starve, and I’ll get my things.”
    “Yes, dear. Is – is Sprockets behaving well?”
    “Tolerably,” said the doctor. “Tolerably.” And he dashed into the house to get all manner of unnecessary things he thought he would need.
    By the time they were ready to depart, Mrs. Bailey had a huge lunch basket packed with sandwiches, chicken, sausages, pickles, olives, plums, ice cream, cake, and all manner of special goodies for Ilium and Leli.
    “Now don’t let Jim hog the plums,” she said. “He’s a perfect pig about plums. They are the first of the season, and there are only two apiece. Did you hear me, Jim?”
    “Yes, Mom,” Jim replied, hurriedly stuffing some pebbles from the courtyard into his pockets. “What would you like me to bring you from the Moon?”
    “A moonstone, of course,” she said. “Now take good care of your father, and be a good boy. And, Sprockets, you keep an eye on both of them.”
    She kissed them all good-by and stood waving to them in the courtyard as the saucer rose humming into the night.
    They rose slowly at first, then faster and faster, though actually it didn’t seem that the saucer was moving at all. This was because Ilium had switched on the under-gravity nullifiers. The only way that Sprockets could tell that the saucer was really moving was to see the Earth becoming smaller and smaller on one side, and the Moon growing larger and larger on the other.
    The only way to describe it, he thought, was in the doctor’s words. It really was a tantalizing, titillating, terrigenous humdinger of a sight.

Chapter 8: He Visits the Dark Side
    For a while everyone kept rushing from one side of the saucer to the other to flatten his nose against the transparent wall and stare, first at the retreating Earth, then at the swiftly approaching Moon. As the Moon grew bigger and brighter they forgot the cloudy Earth and peered wonderingly at the great peaks and craters coming closer second by second.
    “Look!” cried Jim, stuffing another plum into his mouth. “We’re flying over the Mare Imbrium. It isn’t really a sea, Sprockets. It’s only a desert that looks like a sea.”
    “Yes,” said Sprockets, who was well informed about Moon matters from his learning tapes. “You are eating entirely too many plums.”
    “I’m not either. Wow! Look at that big crater. It must be Archimedes.”
    “It is,” said Sprockets. “And you are, too, eating too many plums.”
    “No, I’m not! I like plums.” Jim put another pebble and a plum into the atomic transmuter, and dozens of new plums spilled over the transmuter’s tray. He selected one, popped it into his mouth, and bubbled: “What a place! We’re almost there, and I’m going to be the first boy ever to set foot on it!”
    “Not at the piggy rate you’re going,” Sprockets declared.
    “Aw, what’s a plum or two?”
    “If you don’t stop eating them,” Sprockets warned, “you are going to have a terrigenous humdinger of a stomach-ache.”
    “But I’ve only eaten a few!”
    “You have eaten exactly sixty-nine plums in the seventeen and a half minutes since we left home,” Sprockets reminded him. “How are you going to hunt for quantic moonstones with a stomach-ache?”
    “If quantic moonstones will cure purple dimness, they ought to cure a stomachache.” Jim ate three more plums, then exclaimed: “Say, do you suppose there are people on the dark side of the Moon? Why don’t you ask Ilium?”
    “There are no people left on the Moon,” Sprockets told him, after a musical exchange with Ilium. “They flew away a million years ago. But Ilium says there are things.”
    “Huh?” Jim dropped a plum and stared at him. “What kind of things?”
    “They are dark things, because they live on the dark side. Their exact nature is unknown, but Ilium says they are closely related to some life forms of nonmatter.”
    “Huh?” Jim clutched his stomach. “Life forms of nonmatter? That doesn’t sound so good.”
    “I understand it is even worse to see them, especially if one has a stomach-ache.”
    “Ugh.” Jim was turning a little green. Suddenly he sat down on the floor with his head against the atomic transmuter and clutched his stomach.
    “Sir,” Sprockets said to the doctor, “Jim has a stomach-ache. I think it’s a plum-dinger of a plumdilly.”
    “Naturally,” said the doctor. “But he’ll just have to ache. My degrees are in science, not in medicine. Bless me! It didn’t take us any time to get here – we’re over the Appenine Mountains already. Ask Ilium how fast the saucer can travel, and what makes it go.”
    “It can travel much faster than light,” Sprockets translated. “And, at maximum, it approaches the speed of thought. At the moment we are moving only twenty thousand miles a minute, which Ilium says is a safe speed for you. Otherwise, you might become dreadfully addled, even with the nullifiers on. He says that the hyper-sub-medio space inductors are connected with a thought thingummy, and all he has to do is think for it to go, this way or that way, and as fast as he wants, and that’s the way it goes. Therefore you might say, sir, that we are flying thoughtfully.”
    “Quite simple,” said the doctor. “Quite simple indeed. Ah! We are approaching the dark side. We’d better get our equipment ready.” He was trembling with excitement, his mop of white hair standing out in every direction.
    Even as the doctor spoke, they shot past the mountains, and past the edge of light where awesome craters dipped away into mysterious blackness. Now everything below them was lost in a dreadful expanse of blue-black nothingness – the sort of nothingness where almost anything was likely to be, especially things.
    It was so mysterious that Jim actually forgot his stomach-ache while he stared with open mouth at the dark side’s blackness.
    “I can’t see a thing,” said Don José.
    “I don’t think I want to see a thing,” Jim told him.
    Before Sprockets could adjust his night vision button, Leli pressed something into his hand.
    “Here are the atomic night goggles for your friends,” she sang to him. “And these little belts are really force globes. You fasten one about your waist, press this button, and instantly you are enclosed by a force field that acts like a space suit. It makes air that surrounds you, and keeps the air warm no matter how cold it is outside. Be sure to wear one too, so you won’t get Moon dust in your joints.”
    “Thank you most spectrumly,” Sprockets sang to her.
    “And I hope you have a really purplely time when we land,” she sang back. “We will land very soon and go hunting for quantic moonstones.”
    Sprockets passed the force globe belts and the night goggles around, and everyone fastened them on. There were sudden exclamations as the night goggles disclosed what lay below them. Then there was absolute silence. You could have heard a pin bounce after it was dropped.
    Now Sprockets, who was dutifully picking up all the plum pits that Jim had forgotten, hastily turned on his night vision so he could see what had startled everyone. He was careful, however, not to touch his imagination button, for it took no imagination whatever to imagine things below him that would rattle his cogs and fairly fizzle his circuits.
    Then, timidly, he looked.
    His cogs rattled. It was all he could do not to turn away from the sight, and he wished he had a courage button to help him. He needed it, for the dark side of the Moon was perfectly dreadful.
    It was all up and down and in and out, with deep darkness folding into deeper darkness everywhere. He could see right through the darkness, and every bit of it was broken into jagged canyons, bottomless holes and craters, endless twisting caves, demon bridges and yawning pits blacker than black on black. The worst of it was that you could almost see things moving in the blacker than black on black places. Almost, but not quite, which is far worse than actually seeing them.
    After a few moments Dr. Bailey whispered, “Whew!”
    Don José Salazar whispered, “Whe-e-e-ew!”
    Jim whispered, “Ugh!”
    Sprockets gave several loud tocks.
    “Isn’t it just purplely, glowingly, beautiful?” Leli sang delightedly. “But wait till you see the cave where the quantic moonstones are found. There’s absolutely nothing like it in the galaxy.”
    The saucer dipped down into a tremendous blackness. After it had descended several miles (Sprockets refused to allow himself to compute the distance) into a gorge that seemed to have no bottom, it turned suddenly and shot into a cave. Not just an ordinary cave, because all the ordinary caves on earth could have been crammed into this one, with plenty of room left over for all the tunnels and a subway or two besides. It was miles high, miles wide, and miles and miles long.
    And it was not purplishly beautiful. It was more on the scaryish side.
    It twisted all around and in and out of itself, glowing scaryishly green in places, and scaryishly blue in others; and even the black parts – the most scaryish of all – shone like shiny black velvet. Far inside was an area of bright glinting stretches that looked like lakes of frozen quicksilver, which they were. And all around the lakes were strange black buildings that made everyone think of crumbling castles – curiously spindly crumbling castles.
    “Wow!” cried Jim in an awed voice. “So this is where the Moon people used to live!”
    “Magnificent!” burbled the doctor, his hair beginning to stand straight up, stiff as a brush.
    “Magneeficently dreadful,” said Don José, his mustachios quivering. “Such a place, she gives me the jeebee-heebees. My poor camera, how can she take peectures here?” He shook his head. “I would need an atomic lens, with night vision.”
    “Sprockets,” said the doctor, “ask Ilium where the quantic moonstones are found, and why they don’t make as many as they want in the atomic transmuter?”
    “Sir,” said Sprockets, who had his answers all ready, “quantic moonstones are the only things in the universe made of quantic atoms, and therefore they cannot be reproduced. Ilium says that only nine have ever been found, and only in this area of the quicksilver lakes. They can be anywhere around here – on the shores of the lakes, in the castles, or even in the nests of the things.”
    “Eh?” said the doctor. “What about these things? Are they dangerous?”
    “Not exactly, sir. But Ilium says they are unpurplishly disconcerting. They are simply huge, sir, and being made of nonmatter, they can fly right through one when they are confused. They live up in the darker and more crumbly parts of the castles and, according to Ilium’s description, I would say they closely resemble certain Earth creatures of the order Chiroptera.”
    “Chiroptera?” said Jim. “Why, that’s bats. They’re nothing but Moon bats!”
    “Bless me!” said the doctor. “Naturally, in a place like this, there would be Moon bats. And naturally, they would be large. Fortunately I brought climbing sticks for all of us, so we can easily chase them off.”
    “But, sir,” Sprockets told him dolefully, “one does not chase them off with sticks. Ilium says they have to be thought away.”
    “Eh? What’s this? You have to think them away?”
    “Yes, sir. Things always have to be thought away.” Sprockets’ little voice was suddenly very solemn. “It seems, sir, that human thought, properly directed, is a very potent weapon. But I am not so sure about positronic thought. It may be, sir, that the thinking of a small robot like myself will be dreadfully ineffectual.”
    Jim said: “I’ll bet if you turn on your cerebration button, you can chase a whole flock of ’em away. Anyway, Sprockets, I’ll stay close to you. And if there’s any trouble—”
    “How can we communicate? The Moon is airless, and sound does not travel in a vacuum.”
    “Oh, Daddy brought wrist radios for us. Better strap yours on. We’re going to land.”
    “I don’t need one,” Sprockets said. “I have a special microscopic positronic one built into my circuits. How is your stomachache?”
    “I’ve been practicing on thinking it away. After all, an ache is only a form of nonmatter, and I’m not going to let it keep me from being the first boy to set foot on the Moon. Well – here we are!”

Chapter 9: He Encounters Moon Bats
    The purple saucer floated down and came to a rest a few feet above the shore of one of the quicksilver lakes. On either side rose black crumbling castles with greenishly dark openings where almost anything could be watching.
    “Turn on your wrist radios,” ordered the doctor. “Testing, testing – can everyone hear me?”
    “We hear you,” said Jim and Don José.
    “I hear you, sir,” said Sprockets, adjusting the radio button on the side of his head.
    “Sprockets,” said the doctor, “test with Ilium and Leli. You are our connecting link with them, and we must all remain closely in touch every moment we are on the Moon.”
    “Yes, sir.” Sprockets did as directed, and then replied, “Everything is purplishly well, sir.”
    “Very good,” said the doctor. “Turn on your force globes.”
    Instantly everyone in the saucer was surrounded by a shimmering bubble of protecting force.
    “Now,” said the doctor, his voice tingling with suppressed eagerness, his hair standing up wildly in his force globe, “we will descend upon the Moon. Jim, you and Sprockets stay together, and Don José will stay with me. Never let your partner out of your sight. Test every step you take with your climbing sticks, and report to me every minute on your radios.”
    Ilium thought a command to the saucer, and the slender stairway opened below them and touched the floor of the Moon cave. They all filed slowly, carefully, through the purple veil of light that served as an air lock and down the stairway – all but Jim, who gave a little jump, bounced, and rose several feet before he touched again.
    “Jumping jeepers!” Jim spluttered. “I forgot I don’t weigh anything here!”
    “You weigh one sixth what you do at home,” Sprockets told him. “In spite of the plums.”
    Ilium sang: “I will close the saucer so that things will not enter it while we are absent. I hope you have wonderfully purplish luck and find a quantic moonstone.”
    “Thank you most spectrumly,” said Sprockets with eagerness, “and I hope you find several.”
    “That is too much to hope for,” Leli answered. “They are the most purplishly rare gems in the universe.”
    Ilium and Leli went half floating, half running, like two glowing bubbles, around the shore of the lake. Soon they vanished in the darkness of one of the castles. The doctor and Don José chose another crumbling structure, and presently they, too, were lost to sight.
    Jim looked doubtfully at a third castle, rising tall and gaunt beside the quicksilver lake. It had many dark openings and a flight of ruined steps that wound dizzily up one side.
    “What do you think, Sprockets?” he radioed.
    “It looks dismally dark,” Sprockets replied.
    “It sure does. Dreadfully, dismally dark,” Jim agreed.
    “It’s probably full of Moon dust,” said Sprockets. “And things.”
    “Well, we really could save it till the last.”
    “That might be wise,” said Sprockets. “After all, there’s lots more space outside to hunt in than inside.”
    “So there is,” answered Jim. “Let’s start walking in circles, around and around, and look in all the little holes.”
    So they began moving around and around, poking their climbing sticks into every crack and crevice where a stray quantic moonstone might have been dropped by whoever had dropped it a million years ago. Every minute, regularly, Sprockets would sing out to Ilium and Leli, and then report to the doctor: “All is well, sir, and no one has found anything yet.”
    Walking in his force globe was surprisingly easy, for it changed shape to fit every movement, and gave an extra bounce to his feet. Since he weighed so little on the Moon, he discovered it was no trick at all to leap a dozen feet upward to explore a ledge or the top of a crumbling wall. Quantic moonstones, he was beginning to realize, were not at all easy to find.
    Their circling carried them closer and closer to the gaunt castle with the ruined stairway. Finally they stood directly in front of the largest opening, which was much smaller than the doors of dwellings at home. Far back in the darkness beyond it something gleamed faintly.
    “D’you suppose that’s a quantic moonstone?” Jim whispered.
    “It’s sort of green,” said Sprockets, “so I doubt it. Ilium says quantic moonstones are purple.”
    “It looks sort of purplish to me,” Jim said. “Do you think we ought to investigate it?”
    “That’s up to you,” said Sprockets. “Somehow I don’t feel curious about it at all.”
    “Well, whatever it is, it might make a nice present for Mom.” Jim moved closer to the opening and peered inside. “Er – I’m willing to go in if you are.”
    “I – I’m always willing,” Sprockets answered faintly, and wished he hadn’t been made that way. Having a built-in willingness could be very trying at times, and this was definitely one of the times. He didn’t have to touch his instinct button to know that the door in front of him was a very bad door to enter, and that it would be much better to stay out of it.
    Before Sprockets could think of a good excuse not to enter, Jim had stepped hesitantly inside. Sprockets was almost forced to follow.
    Suddenly Jim exclaimed: “It must be a quantic moonstone! Look how it shines!” And he went bouncing over the rubble on the floor to get it.
    Sprockets was certain by now that it wasn’t what Jim thought it was, and at the same moment he realized what a foolish little robot he had been. He knew exactly how to find what they were all looking for, and he would have been able to find it for them by this time if only he had used his positronic wits.
    My circuits must be affected by the Moon, he told himself, by way of an excuse. Otherwise I surely would have thought of it before.
    He saw Jim pick up the shiny green stone, stand looking at it a moment, then glance overhead, startled.
    “Y – ee – ee – ow!” Jim shrieked. “Run, Sprockets! Run! Moon bats!”
    Sprockets didn’t have a chance to run, for Jim, in his sudden fright, had collided with him and they both fell sprawling. He scrambled quickly to his feet, managed to turn on his cerebration button, and tried mightily to think away the dozens of black flapping shadow things that all at once were filling the lower part of the castle.
    His positronic thinking didn’t seem to help a bit, even with his cerebration button turned on to the last notch.
    All his cerebration button did for him was bring them more quickly to a perfectly awful conclusion.
    He attracted Moon bats!
    There was no doubt about it. He attracted them, and the reason was his atomic battery. They were coming in through all the openings in the place, flapping their great transparent wings, and crowding closer about him, crowding hungrily.
    They looked very much like Earth bats, except that they were big, big, big, and he could see right through them because they were made of nonmatter.
    “Go away!” he screamed at them in his high, tinny little voice. “Go away! Run, Jim! Run!”
    He couldn’t tell what Jim was doing because there were so many bats, suddenly, that they made a swirling black mass of shadows about him, and he could actually begin to feel them draining his battery like nonmatter vampires. The thought of Jim frightened him. Maybe one Moon bat couldn’t hurt a human being – but dozens and dozens of them might be very dangerous to Jim.
    To protect Jim, there was only one thing to do.
    As quick as a wink, before he had time even to give a tock at the thought of what he was doing, he felt behind him and opened his switch box.
    CLICK!
    Sprockets had turned himself off.
    Almost at the same moment he was aware that the edge of the floor beside him was crumbling. There had once been a flight of stairs leading downward here, but for a million years the stairs had been turning to dust. Now, as he fell, helpless, there was nothing to stop him and he continued to fall down, down, down.
    His force globe, which was still turned on, helped cushion his fall a little when he bounced past piles of rubble and scraped over broken steps. Even so, in spite of the fact that his Moon weight was only one sixth his normal weight, he would have been smashed to an unrecognizable clutter of cogs, sprockets, wires, and circuits if he had landed upon anything solid.
    Instead, the bottom of the black dungeon-like pit into which he fell was yards deep in Moon dust, and he settled into it as softly as if he had popped into a black feather bed.
    If his force globe hadn’t been working, the fine Moon dust would have gotten into his joints and seeped right into his circuits, so that soon he would have smothered. All the same, he wondered if smothering wouldn’t have been better than to lie here helpless through all eternity.
    Anyway, Jim was safe, and the Moon bats were gone. He knew this because his positronic radio was still working, and he could faintly hear Jim calling him and then calling the doctor.
    A lot of good it did. He couldn’t reply to Jim and tell where he was, and there was no possible way Jim could find him, lost down here in a Moon dungeon in a smother of dust.
    To practice passing the time – and there would be time uncounted ahead of him to pass – he tried counting a few million numbers. It didn’t help a bit. He counted much too fast. For some reason, he didn’t feel a bit as he usually felt when he was turned off. In fact, he felt rather giddy.
    He felt so giddy he made up a jingle – just to feel it tingle – through his positronic circuits.
       Moon bats, Moon bats,
       Flapping everywhere;
       Why do they flap
       When there isn’t any air?
    How silly, he thought. Being nonmatter, they flap on the magnetic waves, of course.
    He tried another rhyme, trying to make it better than the first, which was really rather dreadful.
       Moon bats, Moon bats,
       How many have I seen?
       Ten, ten, double ten,
       Forty-five, fifteen.
    Oh, dear me, he thought. I’ll never be a Shelley or a Longfellow. And anyhow, there were twice that many bats. He was trying to think of something else to tingle his circuits when he heard a little singing cry on his radio. It was so startling that it almost made him move. In fact, it did make him move the merest trifle, though he didn’t realize it immediately.
    “Oh, Sprockets, help!” came Leli’s cry. “Help! Help! Ilium is hurt! I’m afraid he’s dying!”
    “I hear you,” he tried to answer, though he knew it was impossible to say a word. He could only hear, and faintly at that.
    What could he do?
    He had to do something.
    Then he remembered that his cerebration button was still on full, and that he had moved the merest trifle when he heard Leli’s call.
    Maybe he could turn himself on. With his battery off, he would have to manage it with his brain alone.
    He put all he had into thinking his hand around to his switch. Again he heard Leli crying for help. It gave such a desperate surge to his thoughts that his little hand began inching behind him. It stopped, and he was powerless for a moment as he almost blanked out. Then Leli cried once more and there was such fear and grief in the cry that his hand moved again and touched his switch.
    CLICK!
    Sprockets had turned himself on.
    It was something that no robot had ever done before. For a moment he blanked out completely from the terrible effort of it, but his battery took over and he sat up in the dust calling: “I hear you, Leli! Have courage. I am sending help immediately.”

Chapter 10: He Uses His Buttons
    The first thing was to call the doctor.
    “Dr. Bailey! Dr. Bailey! Sprockets calling! Emergency!”
    “I hear you, Sprockets,” came the doctor’s voice. “Where are you? Jim said you vanished in a cloud of Moon bats. Are you all right?”
    “Forget about me, sir. Ilium is badly hurt. Leli needs help immediately.”
    “Heaven preserve us! Where are they?”
    “I don’t know, sir. I hoped you did, for you went in their direction. I’ve had an accident and been out of contact. I’ll try to locate them. Leli,” he sang, “Leli – how can we find you?”
    “Oh, Sprockets, I’m not sure,” she answered tremulously. “I was following Ilium and not watching how we got here. I think we passed two lakes after we left you, and many castles. Twelve at least.”
    “Can you see the saucer from where you are?”
    “No. The cave curves and hides it. Oh, Sprockets” – her voice broke – “we’ve got to do something fast!”
    “Can you carry Ilium?”
    “Not any farther. I’ve been carrying him, but it’s impossible to go on. There are high walls in the way. And I cannot leave him. You see, his force globe is defective. It went off when he was climbing, so of course he fell. In this dreadful cold, and without air, it takes only seconds – I – I got to him as quickly as I could and fastened my force globe around the two of us, but—”
    “Leli, can you call the saucer to you?”
    “No. I cannot control it unless I can see it and direct it.”
    “Oh.” Sprockets was silent a moment, thinking at top positronic speed while he considered every possibility.
    “Leli,” he spoke again, “have courage and be patient. I promise you everything will be all right, but it will take a little time.”
    It would have been very easy if she could have directed the saucer to her, for then the doctor could have followed where it led and helped the two aboard.
    “Dr. Bailey,” he called, “Leli is not sure of her location. She passed two lakes and at least twelve castles. I suggest, sir, that you and Don José start in that general direction, and I will follow as soon as possible. Jim, are you near?”
    Jim’s voice said: “I’m outside the place where I lost you. Where are you, Sprockets?”
    Sprockets told him, then asked, “Have you a rope?”
    “No, and neither has Daddy. We forgot and left all our ropes aboard the saucer.”
    Sprockets gave a little tock. He’d been counting on someone having a rope. Why hadn’t he been more watchful and looked after the ropes? “Oh, dear me,” he said, “this does complicate matters. What I need is a levitation button.”
    But he did have a balance button, which would help him climb where no human would ever dare set foot.
    “Jim,” he said, “I’m going to attempt to climb out of the pit. I want you to stand in the doorway and think away the Moon bats when they appear. They are attracted by my atomic battery, and they drain my power.”
    “I’ll think ’em away,” Jim said fiercely. “I’ll think ’em clear around to the other side of the Moon if I have to. Start climbing, Sprockets! We’re all counting on you.”
    Sprockets began floundering through the dust. It was a little like being a bug in the bottom of a flour barrel. He soon discovered he could make much better progress by trying to swim through it, which he did. Finally he touched the side of the pit, dug his strong little fingers into a crack, and began clawing his way upward.
    When his head emerged above the dust, he stopped, turned on his balance button, and blinked his eye lights thoughtfully around.
    What he saw was not at all reassuring. The pit stretched at least fifty feet upward, and hardly any of the stairway was left. His fall must have crumbled most of what remained. Worst of all, the pit narrowed at the top.
    “I’ll worry about that when I get there,” he told himself, and began climbing, thankful that he didn’t have a worry button to complicate matters.
    If he had been made of human stuff, with ordinary soft fingers and fingernails, he would have worn his fingers right down to little nubbins in practically no time. As it was, there were places where even his strong metal fingertips could find no grip on the wall. The wall was obviously of a different substance than the vanished stairway – probably it had been chiseled out of the hard Moon rock.
    He solved this problem by taking his screwdriver from the tool kit in his pocket, and using it to dig out tiny holes just large enough to insert the tip of a finger.
    Then, hanging by a finger at a time, he would reach as high as his short arms would stretch and dig another hole where he could cling with another finger. Boiled down, it was all a matter of positronic balance, positronic juggling with the screwdriver, positronic hope, and all the positronic thinking he could pour into it.
    He was halfway up the wall, clinging like a fly, when the first great dark shadow swooped down upon him.
    Sprockets paid no attention to it. He couldn’t afford to notice it, but he could almost hear Jim thinking it away.
    The shadow vanished. Other shadows came, and most of them vanished too. But finally there were so many shadows that Jim could not deal with them all.
    By now, however, Sprockets had reached the curve in the wall.
    “Jim,” he asked, “is my climbing stick up there on the floor?”
    “Yes,” said Jim, “it’s right where you dropped it when the bats first came.”
    “Then hook my stick to your stick, and let it down toward me. Don’t try to pull me up. Just lie down on the floor and hold tight, and I’ll climb up the sticks.”
    Each climbing stick had a strong hook at the end. Presently Sprockets saw the handle of one stick dangling above him.
    “Ready?” he called.
    “Climb away!” said Jim.
    A few seconds later Sprockets hauled himself out of the pit. With him came a circling cloud of Moon bats.
    They raced outside, followed by the bats.
    Sprockets cried: “My battery attracts them! I’ll have to turn myself off till you think them away!”
    CLICK!
    He was turned off again, and thankfully so, for he had used up so much energy and positronic brain power escaping from the pit that he was almost ready to blank out, and he simply couldn’t stand those vampirish bats nibbling at him.
    Then, faintly, he heard Leli’s frantic voice calling: “Oh, Sprockets! Please hurry! Please!”
    Her voice jolted his circuits. It was suddenly terrible to have to stand there, motionless and helpless, while Jim furiously thought the bats away. But finally the bats vanished, and Jim turned him on.
    Sprockets began to run.
    “I’m coming, Leli!” he said. “Keep calling. It will guide me to you.” To Jim he said, “I’m going to Leli – follow me and think the Moon bats away if they return.”
    His little feet flew over the dusty rock of the Moon cave. Jim followed, close at his heels. They jumped cracks, bounced over walls, and raced along the shores of the frozen lakes. With Leli calling, it was a simple matter for Sprockets to determine her direction and go directly to her. He saw no Moon bats – probably because Jim thought them away – nor did he see the doctor, though he could hear him talking worriedly somewhere with Don José.
    He found Leli crouched under a crumbling wall, clinging tightly to Ilium so that her force globe would cover them both.
    Sprockets stooped, caught them up together in his small arms, leaped over the wall, and raced back the way he had come. As he ran he called the doctor to return. He was surprised how little Ilium and Leli weighed, even here on the Moon. He could have carried ten times as much.
    When they sighted the saucer in the distance, Leli directed it to them. They reached it at the same time as Don José and the doctor.
    Within the saucer, Sprockets placed Ilium on one of the bunks. Leli sank down beside Ilium, her tiny hands clasped. The doctor and Don José hovered near, helpless and dejected.
    Sprockets said, “Isn’t there anything we can do, Leli?”
    “No,” she said sadly, “it is too late. See how dim he is? Soon his inner glow will be gone.”
    Suddenly Sprockets burst forth hopefully, “But wouldn’t a quantic moonstone help?”
    “Yes,” she whispered, “if we had one. This is what they are for. But they are so rare. We – we didn’t really expect to find one. We just – hoped—” She began to cry.
    Sprockets whirled away. “Jim, get a rope and follow me!” he begged. “Hurry!”
    He clicked on his force globe, rushed through the purple veil of the air lock, and jumped down the stairway. His cerebration button and his balance button were already turned up high, and now a halo of color began flashing merrily around his head as he turned on his instinct and his special perceptor buttons.
    In the Moon cave he paused just long enough to see if there was anything distantly teasing his circuits, then boldly he turned on his ultraviolet perceptors.
    That did it.
    Looking now like a doubly hot hobgoblin, he could feel something far below one of the castles glowing in return. He raced in the direction of it, Jim close behind.
    With so many buttons turned on, he knew he couldn’t last long. But that didn’t matter – if only he could last long enough. Even the Moon bats didn’t matter, and already they were beginning to come in droves, attracted by his ultraviolet perceptors – which made them practically mad with vampirish hunger.
    As he reached the gaunt structure where he could feel the glow, Sprockets tied the end of Jim’s rope about him and plunged inside. The passageway leading below was choked with Moon dust. He dove into it and wiggled and swam downward.
    He was wiggling rather feebly by the time his hand closed over the shining purple object as large as a hen’s egg. He was hardly wiggling at all when Jim finally hauled him up, even though he had turned off all his buttons.
    He pressed the object into Jim’s hand, and said, faintly: “Run – give it to Leli. It’s a quantic moonstone – it will save Ilium—”
    Slowly, feebly, Sprockets started back to the saucer, surrounded by a growing cloud of Moon bats. Somehow he made it as far as the saucer’s stairway, and then he collapsed.
    Poor little Sprockets was completely used up.
    Naturally, being used up, he had no memory afterward of being hauled into the saucer, and of Ilium’s miraculous recovery with the help of the quantic moonstone. Nor was he aware of the rapid flight home, which took only sixteen and a half minutes.
    Poor little Sprockets was so used up that he didn’t even respond to the hot shot that Mrs. Bailey tearfully gave him, and it was only after he had been visited by seven robot doctors from the Consolidated Mechanical Men Corporation, and two positronic experts wearing white jackets and thick glasses, that he began to tick again.
    When he finally sat up, blinking his eye lights, Mrs. Bailey tucked him right back under the covers, with happy tears in her eyes, and said: “Just lie quietly, dear, and take your medicine. A special inductive sizzle every hour on the half, and you’ll be fit as a fiddle in no time.”
    “You are so kind, ma’am,” he replied, taking his sizzle, which was really quite pleasant and soothing. “Where are Ilium and Leli?”
    “They had to be on their way, but they left you a message tape. Do you feel strong enough to hear it?”
    “Oh, please! Put it in my slot.”
    Mrs. Bailey did so, and he heard Leli singing happily through his circuits. It was a long message, and quite purplishly glowingly spectrumly beautiful. Since it was a private message, it cannot be given here – except to say that Ilium and Leli promised to return soon and give him a present.
    “Now,” said Mrs. Bailey, “I have a little surprise for you. Barnabas says you have behaved tolerably. Quite tolerably. When Barnabas says tolerably, he really means super, super. So we decided to keep you for keeps. Your name is now Sprockets Bailey.”
    “Oh, ma’am!” Sprockets was almost overcome with joy.
    “Furthermore,” said Mrs. Bailey, “we didn’t want you to be lonesome after Jim starts back to school, so we put in a special order at the factory. Jim,” she called. “Bring him in.”
    The door opened. Walking timidly in front of Jim was a small robot who looked very much like Sprockets, only he wasn’t quite as big.
    “Sprockets,” said Mrs. Bailey, “this is your little brother, Rivets.”
    Sprockets sat up, blinking ninety to the second, he was so surprised. “Why – why – this is wonderful!”
    “Just wonnerful!” little Rivets agreed, blinking back. “I never thought I’d have a real brudder with a genuine Asimov Positronic brain! Mine’s only semipositronic.”
    “That’s plenty,” said Sprockets, “because between the two of us that makes a brain and a half, which is really super. We’re going to have a lot of fun!”
    And, naturally, they did.

    1963

>>