Transcribers note. 

This etext was produced from Amazing Stories December 1957. Extensiveresearch did not uncover any evidence that the U. S. Copyright on thispublication was renewed. 

 THE MACHINE THAT SAVED THE WORLD

 By

 MURRAY LEINSTER

_They were broadcasts from nowhere--sinister emanations flooding in fromspace--smashing any receiver that picked them up. What defense couldEarth devise against science such as this?_

[Illustration: Did the broadcasts foretell flesh-rending supersonicblasts?]

The first broadcast came in 1972, while Mahon-modified machines werestill strictly classified, and the world had heard only rumors aboutthem. The first broadcast was picked up by a television ham in Osceola, Florida, who fumingly reported artificial interference on the amateur TVbands. He heard and taped it for ten minutes--so he said--before it blewout his receiver. When he replaced the broken element, the broadcast wasgone. 

But the Communications Commission looked at and listened to the tape andpractically went through the ceiling. It stationed a monitor truck inOsceola for months, listening feverishly to nothing. 

Then for a long while there were rumors of broadcasts which blew outreceiving apparatus, but nothing definite. Weird patterns appeared onscreens high-pitched or deep-bass notes sounded--and the receiver wentout of operation. After the ham operator in Osceola, nobody else gotmore than a second or two of the weird interference before blowing hisset during six very full months of CC agitation. 

Then a TV station in Seattle abruptly broadcast interferencesuperimposed on its regular network program. The screens of all setstuned to that program suddenly showed exotic, curiously curved, meaningless patterns on top of a commercial spectacular broadcast. Atthe same time incredible chirping noises came from the speakers, alternating with deep-bass hootings, which spoiled the ju-ju music ofthe most expensive ju-ju band on the air. The interference ended onlywith a minor break-down in the transmitting station. It was the samesort of interference that the Communications Commission had thrown fitsabout in Washington. It threw further fits now. 

 * * * * *

A month later a vision-phone circuit between Chicago and Los Angeles wasunusable for ten minutes. The same meaningless picture-pattern and thesame preposterous noises came on and monopolized the line. It ceasedwhen a repeater-tube went out and a parallel circuit took over. Again, frantic agitation displayed by high authority. 

Then the interference began to appear more frequently, though stillcapriciously. Once a Presidential broadcast was confused by interferenceapparently originating in the White House, and again a three-waytop-secret conference between the commanding officers of three militarydepartments ceased when the unhuman-sounding noises and the scrambledpicture pattern inserted itself into the closed-circuit discussion. Theconference broke up amid consternation. For one reason, militarycircuits were supposed to be interference-proof. For another, itappeared that if interference could be spotted to this circuit or thisreceiver it was likely this circuit or that receiver could be tapped. 

For a third reason, the broadcasts were dynamite. As received, theywere badly scrambled, but they could be straightened out. Even the firstone, from Osceola, was cleaned up and understood. Enough so to make topauthority tear its hair and allow only fully-cleared scientificconsultants in on the thing. 

The content of the broadcasts was kept considerably more secret than theexistence of Mahon units and what they could do. And Mahon units werebrand-new, then, and being worked with only at one research installationin the United States. 

The broadcasts were not so closely confined. The same wriggly patternsand alien noises were picked up in Montevideo, in Australia, in PanamaCity, and in grimly embattled England. All the newspapers discussed themwithout ever suspecting that they had been translated into plain speech. They were featured as freak news--and each new account mentioned thatthe broadcast reception had ended with a break-down of the receivingapparatus. 

Guarded messages passed among the high authorities of the nations thatpicked up the stuff. A cautious inquiry went even to the Compubs. 

The Union of Communist Republics answered characteristically. It asked aquestion about Mahon units. There were rumors, it said, about a newprinciple of machine-control lately developed in the United States. Itwas said that machines equipped with the new units did not wear out, that they exercised seeming intelligence at their tasks, and that theypromised to end the enormous drain on natural resources caused by thewearing-out and using-up of standard-type machinery. 

The Compub Information Office offered to trade data on the broadcastsfor data about the new Mahon-modified machines. It hinted at extremelyimportant revelations it could make. 

The rest of the world deduced astutely that the Compubs were scared, too. And they were correct. 

 * * * * *

Then, quite suddenly, a break came. All previous broadcast receptionshad ended with the break-down of the receiving instrument. Now acommunicator named Betsy, modified in the Mahon manner and at work inthe research installation working with Mahon-modified devices, began topick up the broadcasts consistently, keeping each one on its screenuntil it ended. 

Day after day, at highly irregular intervals, Betsy's screen lighted upand showed the weird patterns, and her loudspeakers emitted the peepingsand chirps and deep-bass hootings of the broadcasts. And the high brasswent into a dither to end all dithers as tapes of the received materialreached the Pentagon and were translated into intelligible speech andpictures. 

 * * * * *

This was when Metech Sergeant Bellews, in charge of the Rehab Shop atResearch Installation 83, came into the affair. Specifically, he enteredthe picture when a young second lieutenant came to the shop to fetch himto Communications Center in that post. 

The lieutenant was young and tall and very military. Sergeant Bellewswas not. So he snorted, upon receipt of the message. He was at work on avacuum cleaner at the moment--a Mahon-modified machine with a flickeringyellow standby light that wavered between brightness and dimness withmuch more than appropriate frequency. The Rehabilitation Shop was whereMahon-modified machines were brought back to usefulness when somebodymessed them up. Two or three machines--an electric ironer, forone--operated slowly and hesitantly. That was occupational therapy. Awashing-machine churned briskly, which was convalescence. Others, ranging from fire-control computers to teletypes and automatic lathes, simply waited with their standby lights flickering meditativelyaccording to the manner and custom of Mahon-modified machines. They wereready for duty again. 

The young lieutenant was politely urgent. 

"But I been there!" protested Sergeant Bellews. "I checked! It's acommunicator I named Betsy. She's all right! She's been mishandled bythe kinda halfwits Communications has around, but she's a good, well-balanced, experienced machine. If she's turning out broadcasts, it's because they're comin' in! She's all right!"

"I know, " said the young lieutenant soothingly. His uniform and hismanners were beautiful to behold. "But the Colonel wants you there for aconference. "

"I got a communicator in the shop here, " said Sergeant Bellewssuspiciously. "Why don't he call me?"

"Because he wants to try some new adjustments on--ah--Betsy, Sergeant. You have a way with Mahon machines. They'll do things for you they won'tdo for anybody else. "

Sergeant Bellews snorted again. He knew he was being buttered up, buthe'd asked for it. He even insisted on it, for the glory of theMetallurgical Technicians' Corps. The big brass tended to regard Metechsas in some fashion successors to the long-vanished veterinary surgeonsof the Farriers' Corps, when horses were a part of the armed forces. Mahon-modified machines were new--very new--but the top brass naturallyremembered everything faintly analogous and applied it all wrong. SoSergeant Bellews conducted a one-man campaign to establish the dignityof his profession. 

But nobody without special Metech training ought to tinker with aMahon-modified machine. 

"If he's gonna fool with Betsy, " said the Sergeant bitterly, "I guess Igotta go over an' boss the job. "

He pressed a button on his work-table. The vacuum cleaner's standbylight calmed down. The button provided soothing sub-threshold stimuli tothe Mahon unit, not quite giving it the illusion of operatingperfectly--if a Mahon unit could be said to be capable of illusion--butmaintaining it in the rest condition which was the foundation ofMahon-unit operation, since a Mahon machine must never be turned off. 

The lieutenant started out of the door. Sergeant Bellews followed atleisure. He painstakingly avoided ever walking the regulation two pacesbehind a commissioned officer. Either he walked side by side, chatting, or he walked alone. Wise officers let him get away with it. 

 * * * * *

Reaching the open air a good twenty yards behind the lieutenant, hecocked an approving eye at a police-up unit at work on the lawn outside. Only a couple of weeks before, that unit had been in a bad way. Itstopped and shivered when it encountered an unfamiliar object. 

But now it rolled across the grass from one path-edge to another. Whenit reached the second path it stopped, briskly moved itself its ownwidth sidewise, and rolled back. On the way it competently manicured thelawn. It picked up leaves, retrieved a stray cigarette-butt, and snappedup a scrap of paper blown from somewhere. Its tactile units touched anew-planted shrub. It delicately circled the shrub and went on upon itsproper course. 

 * * * * *

Once, where the grass grew taller than elsewhere, it stopped andwhirred, trimming the growth back to regulation height. Then it went onabout its business as before. 

Sergeant Bellews felt a warm sensation. That was a good machine that hadbeen in a bad way and he'd brought it back to normal, happy operation. The sergeant was pleased. 

The lieutenant turned into the Communications building. Sergeant Bellewsfollowed at leisure. A jeep went past him--one of the special jeepsbeing developed at this particular installation--and its driver wastalking to someone in the back seat, but the jeep matter-of-factlyturned out to avoid Sergeant Bellews. He glowed. He'd activated it. Another good machine, gathering sound experience day by day. 

He went into the room where Betsy stood--the communicator which, aloneamong receiving devices in the whole world, picked up the enigmaticbroadcasts consistently. Betsy was a standard Mark IV communicator, nowcarefully isolated from any aerial. She was surrounded by recordingdevices for vision and sound, and by the most sensitive and complicatedinstruments yet devised for the detection of short-wave radiation. Nothing had yet been detected reaching Betsy, but something must. Nomachine could originate what Betsy had been exhibiting on her screen andemitting from her speakers. 

Sergeant Bellews tensed instantly. Betsy's standby light quiveredhysterically from bright to dim and back again. The rate of quiveringwas fast. It was very nearly a sine-wave modulation of the light--andwhen a Mahon-modified machine goes into sine-wave flicker, it is thesame as Cheyne-Stokes breathing in a human. 

He plunged forward. He jerked open Betsy's adjustment-cover and fairlyyelped his dismay. He reached in and swiftly completed correctivechanges of amplification and scanning voltages. He balanced a capacitybridge. He soothed a saw-tooth resonator. He seemed to know by sheerintuition what was needed to be done. 

After a moment or two the standby lamp wavered slowly fromnear-extinction to half-brightness, and then to full brightness andback again. It was completely unrhythmic and very close to normal. 

"Who done this?" demanded the sergeant furiously. "He had Betsy close tofatigue collapse! He'd ought to be court-martialed!"

He was too angry to notice the three civilians in the room with thecolonel and the lieutenant who'd summoned him. The young officer lookeduncomfortable, but the colonel said authoritatively:

"Never mind that, Sergeant. Your Betsy was receiving something. Itwasn't clear. You had not reported, as ordered, so an attempt was madeto clarify the signals. "

"Okay, Colonel!" said Sergeant Bellews bitterly. "You got the right tospoil machines! But if you want them to work right you got to treat 'emright!"

"Just so, " said the colonel. "Meanwhile--this is Doctor Howell, DoctorGraves, and Doctor Lecky. Sergeant Bellews, gentlemen. Sergeant, theseare not MDs. They've been sent by the Pentagon to work on Betsy. "

 * * * * *

"Betsy don't need workin' on!" said Sergeant Bellews belligerently. "She's a good, reliable, experienced machine! If she's handled right, she'll do better work than any machine I know!"

"Granted, " said the colonel. "She's doing work now that no other machineseems able to do--drawing scrambled broadcasts from somewhere that canonly be guessed at. They've been unscrambled and these gentlemen havecome to get the data on Betsy. I'm sure you'll cooperate. "

"What kinda data do they want?" demanded Bellews. "I can answer mostquestions about Betsy!"

"Which, " the colonel told him, "is why I sent for you. These gentlemenhave the top scientific brains in the country, Sergeant. Answer theirquestions about Betsy and I think some very high brass will be grateful. 

"By the way, it is ordered that from now on no one is to refer to Betsyor any work on these broadcasts, over any type of electroniccommunication. No telephone, no communicator, no teletype, no radio, noform of communication except _viva voce_. And that means you talking tosomebody else, Sergeant, with no microphone around. Understand? And fromnow on you will not talk about anything at all except to these gentlemenand to me. "

Sergeant Bellews said incredulously:

"Suppose I got to talk to somebody in the Rehab Shop. Do I signal withmy ears and fingers?"

"You don't talk, " said the colonel flatly. "Not at all. "

Sergeant Bellews shook his head sadly. He regarded the colonel with suchreproach that the colonel stiffened. But Sergeant Bellews had a gift formachinery. He had what amounted to genius for handling Mahon-modifieddevices. So long as no more competent men turned up, he was apt to getaway with more than average. 

The colonel frowned and went out of the room. The tall young lieutenantfollowed him faithfully. The sergeant regarded the three scientists withthe suspicious air he displayed to everyone not connected with Mahonunits in some fashion. 

"Well?" he said with marked reserve. "What can I tell you first?"

Lecky was the smallest of the three scientists. He said ingratiatingly, with the faintest possible accent in his speech:

"The nicest thing you could do for us, Sergeant, would be to show usthat this--Betsy, is it?--with other machines before her, has developeda contagious machine insanity. It would frighten me to learn thatmachines can go mad, but I would prefer it to other explanations for themessages she gives. "

"Betsy can't go crazy, " said Bellews with finality. "She'sMahon-controlled, but she hasn't got what it takes to go crazy. A Mahonunit fixes a machine so it can loaf and be a permanent dynamic systemthat can keep acquired habits of operatin'. It can take trainin'. It canget to be experienced. It can learn the tricks of its trade, so tospeak. But it can't go crazy!"

"Too bad!" said Lecky. He added persuasively: "But a machine can lie, Sergeant? Would that be possible?"

Sergeant Bellews snorted in denial. 

 * * * * *

"The broadcasts, " said Lecky mildly, "claim a remarkable reason forcertainty about an extremely grave danger which is almost upon theworld. If it's the truth, Sergeant, it is appalling. If it is a lie, itmay be more appalling. The Joint Chiefs of Staff take it very seriously, in any case. They--"

"I got cold shivers, " said Sergeant Bellews with irony. "I'm all wroughtup. Huh! The big brass gets the yellin' yollups every so often anyhow. Listen to them, and nothin' happens except it's top priority top secretextra crash emergency! What do you want to know about Betsy?"

There was a sudden squealing sound from the communicator on which allthe extra recording devices were focussed. Betsy's screen lighted up. Peculiarly curved patterns appeared on it. They shifted and changed. Noises came from her speaker. They were completely unearthly. Now theywere shrill past belief, and then they were chopped into very small bitsof sound, and again they were deepest bass, when each separate noteseemed to last for seconds. 

"You might, " said Lecky calmly, "tell us from where your Betsy gets thesignal she reports in this fashion. "

There were whirrings as recorders trained upon Betsy captured everyflickering of her screen and every peeping noise or deep-toned rumble. The screen-pattern changed with the sound, but it was not linked to it. It was a completely abnormal reception. It was uncanny. It was somehowhorrible because so completely remote from any sort of humancommunication in the year 1972. 

The three scientists watched with worried eyes. A communicator, evenwith a Mahon unit in it, could not originate a pattern like this! Andthis was not conceivably a distortion of anything transmitted in anynormal manner in the United States of America, or the Union of Compubs, or any of the precariously surviving small nations not associated witheither colossus. 

"This is a repeat broadcast!" said one of the three men suddenly. It wasHowell, the heavy-set man. "I remember it. I saw it projected--likethis, and then unscrambled. I think it's the one where the socialsystem's described--so we can have practice at trying to understand. Remember?"

 * * * * *

Lecky said, as if the matter had been thrashed out often before:

"I do not believe what it says, Howell! You know that I do not believeit! I will not accept the theory that this broadcast comes from thefuture!"

The broadcast stopped. It stopped dead. Betsy's screen went blank. Herwildly fluctuating standby light slowed gradually to a nearly normalrate of flicker. 

"That's not a theory, " said Howell dourly. "It's a statement in thebroadcast. We saw the first transmission of this from the tape at thePentagon. Then we saw it with the high-pitched parts slowed down and thedeep-bass stuff speeded up. Then it was a human voice giving data on thescanning pattern and then rather drearily repeating that history saidthat intertemporal communication began with broadcasts sent back from2180 to 1972. It said the establishment of two-way communication wasvery difficult and read from a script about social history, to give uspractice in unscrambling it. It's not a theory to say the stufforiginates in the future. It's a statement. "

"Then it is a lie, " said Lecky, very earnestly. "Truly, Howell, it is alie!"

"Then where does the broadcast come from?" demanded Howell. "Some sayit's a Compub trick. But if they were true they'd hide it for use toproduce chaos in a sneak attack. The only other theory--"

 * * * * *

Graves, the man with the short moustache, said jerkily:

"No, Howell! It is not an extra-terrestrial creature pretending to be aman of our own human future. One could not sleep well with such an ideain his head. If some non-human monster could do this--"

"I do not sleep at all, " said Lecky simply. "Because it says thattwo-way communication is to come. I can listen to these broadcaststranquilly, but I cannot bear the thought of answering them. That seemsto me madness!"

Sergeant Bellews said approvingly:

"You got something there! Yes, sir! Did you notice how Betsy's standbylight was wabbling while she was bringin' in that broadcast? If shecould sweat, she'd've been sweating!"

Lecky turned his head to stare at the sergeant. 

"Machines, " said Bellews profoundly, "act according to the golden rule. They do unto you as they would have you do unto them. You treat amachine right and it treats you right. You treat it wrong and it bustsitself--still tryin' to treat you right. See?"

Lecky blinked. 

"I do not quite see how it applies, " he said mildly. 

"Betsy's an old, experienced machine, " said the sergeant. "A signal thatmakes her sweat like that has got something wrong about it. Any ordinarymachine 'ud break down handlin' it. "

Graves said jerkily:

"The other machines that received these broadcasts did break down, Sergeant. All of them. "

"Sure!" said the sergeant with dignity. "O' course, who's broadcastin'may have been tinkerin' with their signal since they seen it wasn'tgettin' through. Betsy can take it now, when younger machines with lessexperience can't. Maybe a micro-microwatt of signal. Then it makes hersweat. If she was broadcastin', with a hell of a lot more'n amicro-microwatt--it'd be bad! I bet you that every machine we make tobroadcast breaks down! I bet--"

Howell said curtly:

"Reasonable enough! A signal to pass through time as well as space wouldbe different from a standard wave-type! Of course that must be theanswer. "

Sergeant Bellews said truculently:

"I got a hunch that whoever's broadcastin' is busting transmitters rightan' left. I never knew anything about this before, except that Betsy waspickin' up stuff that came from nowhere. But I bet if you look over therecord-tapes you will find they got breaks where one transmitterswitched off or broke down and another took over!"

Lecky's eyes were shining. He regarded Sergeant Bellews with a sort oftender respect. 

"Sergeant Bellews, " he said softly, "I like you very much. You have toldus undoubtedly true things. "

"Think nothin' of it, " said the sergeant, gratified. "I run the RehabShop here, and I could show you things--"

"We wish you to, " said Lecky. "The reaction of machines to thesebroadcasts is the one viewpoint we would never have imagined. But it isplainly important. Will you help us, Sergeant? I do not like to befrightened--and I am!"

"Sure, I'll help, " said Sergeant Bellews largely. "First thing is towhip some stuff together so we can find out what's what. You take a fewMahon units, and install 'em and train 'em right, and they will doalmost anything you've a mind for. But you got to treat 'em right. Machines work by the golden rule. Always! Come along!"

 * * * * *

Sergeant Bellews went to the Rehab Shop, followed only by Lecky. Allabout, the sun shone down upon buildings with a remarkably temporarylook about them, and on lawns with a remarkably lush look about them, and signboards with very black lettering on gray paint backgrounds. There was a very small airfield inside the barbed-wire fence about thepost, and elaborate machine-shops, and rows and rows of barracks and acanteen and a USO theatre, and a post post-office. Everything seemedquite matter-of-fact. 

Except for the machines. 

They were the real reason for the existence of the post. The barracksand married-row dwellings had washing-machines which looked very muchlike other washing-machines, except that they had standby lights whichflickered meditatively when they weren't being used. 

 * * * * *

The television receivers looked like other TV sets, except for minuteand wavering standby lights which were never quite as bright or dim onemoment as the next. The jeeps--used strictly within the barbed-wirefence around the post--had similar yellow glowings on theirinstrument-boards, and they were very remarkable jeeps. They never ranoff the graveled roads onto the grass, and they never collided with eachother, and it was said that the nine-year-old son of a lieutenant-colonelhad tried to drive one and it would not stir. Its motor cut off when heforced it into gear. When he tried to re-start it, the starter did notturn. But when an adult stepped into it, it operated perfectly--only itbraked and stopped itself when a small child toddled into its path. 

There were some people who said that this story was not true, but otherpeople insisted that it was. Anyhow the washing-machines were perfect. They never tangled clothes put into them. It was reported that Mrs. So-and-so's washing-machine had found a load of clothes tangled, andreversed itself and worked backward until they were straightened out. 

Television sets turned to the proper channels--different ones atdifferent times of day--with incredible facility. The smallest childcould wrench at a tuning-knob and the desired station came on. All theoperating devices of Research Installation 83 worked as if they likedto--which might have been alarming except that they never did anythingof themselves. They initiated nothing. But each one acted like an old, favorite possession. They fitted their masters. They seemed to tunethemselves to the habits of their owners. They were infinitely easy towork right, and practically impossible to work wrong. 

Such machines, of course, had not been designed to cope with enigmaticbroadcasts or for military purposes. But the jet-planes on the smallairfield were very remarkable indeed, and the other and lesser deviceshad been made for better understanding of the Mahon units which mademachines into practically a new order of creation. 

 * * * * *

Sergeant Bellews ushered Lecky into the Rehab Shop. There was thepleasant, disorderly array of devices with their wavering standbylights. They gave an effect of being alive, but somehow it was notdisturbing. They seemed not so much intent as meditative, and not somuch watchful as interested. When the sergeant and his guest moved pastthem, the unrhythmic waverings of the small yellow lights seemed tochange hopefully, as if the machines anticipated being put to use. Which, of course, was absurd. Mahon machines do not anticipate anything. They probably do not remember anything, though patterns of operation arecertainly retained in very great variety. The fact is that a Mahon unitis simply a device to let a machine stand idle without losing the natureof an operating machine. 

The basic principle goes back to antiquity. Ships, in ancient days, hadmanners and customs individual to each vessel. Some were sweet craft, easily handled and staunch and responsive. Others were stubborn andbegrudging of all helpfulness. Sometimes they were even man-killers. These facts had no rational explanation, but they were facts. Insimilarly olden times, particular weapons acquired personalities to thepoint of having personal names--Excalibur, for example. 

Every fighting man knew of weapons which seemed to possess personalskill and ferocity. Later, workmen found that certain tools had a knackof fitting smoothly in the hand--seeming even to divine the grain of thewood they worked on. The individual characteristics of violins werenotorious, so that a violin which sang joyously under the bow wasliterally priceless. 

And all these things, as a matter of observation and not ofsuperstition, kept their qualities only when in constant use. Let a shipbe hauled out of water and remain there for a time, and she would beclumsy on return to her native element. Let a sword or tool stay unused, and it seemed to dull. In particular, the finest of violins lost itssplendor of tone if left unplayed, and any violin left in a repair-shopfor a month had to be played upon constantly for many days before itsliving tone came back. 

 * * * * *

The sword and the tool perhaps, but the ship and the violin certainly, acted as if they acquired habits of operation by being used, and lostthem by disuse. When more complex machines were invented, such factswere less noticeable. True, no two automobiles ever handled exactly thesame, and that was recognized. But the fact that no complex machineworked well until it had run for a time was never commented on, exceptin the observation that it needed to be warmed up. Anybody would haveadmitted that a machine in the act of operating was a dynamic system ina solid group of objects, but nobody reflected that a stopped machinewas a dead thing. Nobody thought to liken the warming-up period for anaeroplane engine to the days of playing before a disuse-dulled violinregained its tone. 

Yet it was obvious enough. A ship and a sword and a tool and a violinwere objects in which dynamic systems existed when they were used, andin which they ceased to exist when use stopped. And nobody noticed thata living creature is an object which contains a dynamic system when itis living, and loses it by death. 

For nearly two centuries quite complex machines were started, and warmedup, and used, and then allowed to grow cold again. In time the morecomplex machines were stopped only reluctantly. Computers, for example, came to be merely turned down below operating voltage when not in use, because warming them up was so difficult and exacting a task. Which wasan unrecognized use of the Mahon principle. It was a way to keep amachine activated while not actually operating. It was a state of rest, of loafing, of idleness, which was not the death of a running mechanism. 

The Mahon unit was a logical development. It was an absurdly simpledevice, and not in the least like a brain. But to the surprise ofeverybody, including its inventor, a Mahon-modified machine did morethan stay warmed up. It retained operative habits as no complex devicehad ever done before. In time it was recognized that Mahon-modifiedmachines acquired experience and kept it so long as the standby lightglowed and flickered in its socket. If the lamp went out the machinedied, and when reënergized was a different individual entirely, withoutexperience. 

Sergeant Bellews made such large-minded statements as were needed tobrief Lecky on the work done in this installation with Mahon-controlledmachines. 

"They don't think, " he explained negligently, "any more than dogs think. They just react--like dogs do. They get patterns of reaction. They gettrained. Experienced. They get good! Over at the airfield they'rewalking around beaming happy over the way the jets are flyin'themselves. "

Lecky gazed around the Rehab Shop. There were shelves of machines, dulyboxed and equipped with Mahon units, but not yet activated. Activationmeant turning them on and giving them a sort of basic training in thetasks they were designed to do. But also there were machines which hadbroken down--invariably through misuse, said Sergeant Bellewsacidly--and had been sent to the Rehab Shop to be re-trained in theirproper duties. 

"Guys see 'em acting sensible and obediently, " said Bellews withbitterness, "and expect 'em to think. Over at the jet-field they finallycome to understand. " His tone moderated. "Now they got jets that putdown their own landing-gear, and holler when fuel's running low, and doacrobatics happy if you only jiggle the stick. They mighty near flythemselves! I tell you, if well-trained Mahon jets ever do tangle withold-style machines, it's goin' to be a caution to cats! It'll be like apack of happy terriers pilin' into hamsters. It'll be murder!"

 * * * * *

He surveyed his stock. From a back corner he brought out a small machinewith an especially meditative tempo in its standby-lamp flicker. Thetempo accelerated a little when he put it on a work-bench. 

"They got batteries to stay activated with, " he observed, "and only needreal juice when they're workin'. This here's a play-back recorder they hadover in Recreation. Some guys trained it to switch frequencies--speed-upand slow-down stuff. They laughed themselves sick! There used to be atough guy over there, --a staff sergeant, he was--that gave lectures onmilitary morals in a deep bass voice. He was proud of that bull voiceof his. He used it frequently. So they taped him, and Al here--" thename plainly referred to the machine--"used to play it back switchedup so he sounded like a squeaky girl. That poor guy, he liked to busteda blood-vessel when he heard himself speakin' soprano. He raised helland they sent Al here to be rehabilitated. But I switched another machinefor him and sent it back, instead. Of course, Al don't know what he'sdoing, but--"

 * * * * *

He brought over another device, slightly larger and with a screen. 

"Somebody had a bright notion with this one, too, " he said. "Theyfigured they'd scramble pictures for secret transmission, like theyscramble voice. But they found they hadda have team-trained sets towork, an' they weren't interchangeable. They sent Gus here to bedeactivated an' trained again. I kinda hate to do that. Sometimes yougot to deactivate a machine, but it's like shooting a dog somebody'staught to steal eggs, who don't know it's wrong. "

He bolted the two instruments together. He made connections withflexible cables and tucked the cable out of sight. He plugged in forpower and began to make adjustments. 

The small scientist asked curiously:

"What are you preparing, Sergeant?"

"These two'll unscramble that broadcast, " said Sergeant Bellews, withtranquil confidence. "Al's learned how to make a tape and switchfrequencies expert. Gus, here, he's a unscrambler that can make anykinda scanning pattern. Together they'll have a party doing what they'respecial trained for. We'll hook 'em to Betsy's training-terminals. "

He regarded the two machines warmly. Connected, now, their standbylights flickered at a new tempo. They synchronized, and broke synchrony, and went back into elaborate, not-quite-resolvable patterns which weresomehow increasingly integrated as seconds went by. 

"Those lights look kinda nice, don't they?" asked the sergeantadmiringly. "Makes you think of a coupla dogs gettin' acquainted whenthey're goin' out on a job of hunting or something. "

But Lecky said abruptly, in amazement:

"But, Sergeant! In the Pentagon it takes days to unscramble a receivedbroadcast such as Betsy receives! It requires experts--"

"Huh!" said Sergeant Bellews. He picked up the two machines. "Don't getme started about the kinda guys that wangle headquarters-company jobs!They got a special talent for fallin' soft. But they haven't necessarilygot anything else!"

 * * * * *

Lecky followed Sergeant Bellews as the sergeant picked up his newcombination of devices and headed out of the Rehab Shop. Outside, in thesunshine, there were roarings to be heard. Lecky looked up. A formationof jets swam into view against the sky. A tiny speck, trailing amonstrous plume of smoke, shot upward from the jet-field. The formationtightened. 

The ascending jet jiggled as if in pure exuberance as it swoopedupward--but the jiggle was beautifully designed to throw standardautomatic gunsights off. 

A plane peeled off from the formation and dived at the ascending ship. There was a curious alteration in the thunder of motors. Therate-of-rise of the climbing jet dwindled almost to zero. Sparks shotout before it. They made a cone the diving ship could not avoid. It spedthrough them and then went as if disappointedly to a lower level. Itstood by to watch the rest of the dog-fight. 

"Nice!" said Sergeant Bellews appreciatively. "That's a Mahon jet all byitself, training against regular ships. They have to let it shootstar-bullets in training, or it'd get hot and bothered in a real fightwhen its guns went off. "

The lower jet streaked skyward once more. Sparks sped from theformation. They flared through emptiness where the Mahon jet had beenbut now was not. It scuttled abruptly to one side as concerted streamsof sparks converged. They missed. It darted into zestful, exuberantmaneuverings, remarkably like a dog dashing madly here and there in purehigh spirits. The formation of planes attacked it resolutely. 

Suddenly the lone jet plunged into the midst of the formation, therewere coruscations of little shooting stars, and one-two-three planesdisgustedly descended to lower levels as out of action. Then the singleship shot upward, seemed eagerly to shake itself, plunged back--and thelast ships tried wildly to escape, but each in turn was technically shotdown. 

The Mahon jet headed back for its own tiny airfield. Somehow, it lookedas if, had it been a dog, it would be wagging its tail and pantinghappily. 

"That one ship, " said Lecky blankly, "it defeated the rest?"

"It's got a lot of experience, " said the sergeant. "You can't beatexperience. "

He led the way into Communications Center. In the room where Betsystood, Howell and Graves had been drawing diagrams at each other to thepoint of obstinacy. 

"But don't you see?" insisted Howell angrily. "There can be no sourceother than a future time! You can't send short waves throughthree-dimensional space to a given spot and not have them interceptiblebetween. Anyhow, the Compubs wouldn't work it this way! They wouldn'tput us on guard! And an extra-terrestrial wouldn't pretend to be a humanif he honestly wanted to warn us of danger! He'd tell us the truth!Physically and logically it's impossible for it to be anything but whatit claims to be!"

Graves said doggedly:

"But a broadcast originating in the future is impossible!"

"Nothing, " snapped Howell, "that a man can imagine is impossible!"

"Then imagine for me, " said Graves, "that in 2180 they read in thehistory books about a terrible danger to the human race back in 1972, which was averted by a warning they sent us. Then, from theirhistory-books, which we wrote for them, they learn how to make atransmitter to broadcast back to us. Then they tell us how to make atransmitter to broadcast ahead to them. They don't invent thetransmitter. We tell them how to make it--via a history book. We don'tinvent it. They tell us--from the history book. Now imagine for me howthat transmitter got invented!"

"You're quibbling, " snapped Howell. "You're refusing to face a factbecause you can't explain it. I say face the fact and then ask for anexplanation!"

"Why not ask them, " said Graves, "how to make a round square or afive-sided triangle?"

 * * * * *

Sergeant Bellews pushed to a spot near Betsy. He put down his now-linkedMahon machines and began to move away some of the recording apparatusfocused on Betsy. 

"Hold on there!" said Howell in alarm. "Those are recorders!"

"We'll let 'em record direct, " said the sergeant. 

 * * * * *

Lecky spoke feverishly in support of Bellews. But what he said was, ineffect, a still-marveling description of the possibilities ofMahon-modified machines. They were, he said with ardent enthusiasm, thenext step in the historic process by which successively greater portionsof the cosmos enter into a symbiotic relationship with man. Domesticanimals entered into such a partnership aeons ago. Certain plants--wheatand the like--even became unable to exist without human attention. Andmachines were wrought by man and for a long time served him reluctantly. Pre-Mahon machines were tamed, not domestic. They wore themselves outand destroyed themselves by accidents. But now there were machines whichcould enter into a truly symbiotic relationship with humanity. 

"What, " demanded Howell, "what in hell are you talking about?"

Lecky checked himself. He smiled abashedly:

"I think, " he said humbly, "that I speak of the high destiny of mankind. But the part that applies at the moment is that Sergeant Bellews mustnot be interfered with. "

He turned and ardently assisted Sergeant Bellews in making room for thejust-brought devices. Sergeant Bellews led flexible cables from them toBetsy. He inserted their leads in her training-terminals. He madeadjustments within. 

It became notable that Betsy's standby light took up new tempos in itswavering. There were elaborate interweavings of rate and degree ofbrightening among the lights of all three instruments. There was nopossible way to explain the fact, but a feeling of pleasure, of zestfulstirring, was somehow expressed by the three machines which had beenlinked together into a cooperating group. 

Sergeant Bellews eased himself into a chair. 

"Now everything's set, " he observed contentedly. "Remember, I ain't seenany of these broadcasts unscrambled. I don't know what it's all about. But we got three Mahon machines set up now to work on the next crazybroadcast that comes in. There's Betsy and these two others. And allmachines work accordin' to the Golden Rule, but Mahon machines--they arehoney-babes! They'll bust themselves tryin' to do what you ask 'em. AndI asked these babies for plenty--only not enough to hurt 'em. Let's seewhat they turn out. "

He pulled a pipe and tobacco from his pocket. He filled the pipe. Hesqueezed the side of the bowl and puffed as the tobacco glowed. Herelaxed, underneath the wall-sign which sternly forbade smoking by allmilitary personnel within these premises. 

It was nearly three hours--but it could have been hundreds--beforeBetsy's screen lighted abruptly. 

 * * * * *

The broadcast came in; a new transmission. The picture-pattern onBetsy's screen was obviously not the same as other broadcasts fromnowhere. The chirps and peepings and the rumbling deep sounds were notrepetitions of earlier noise-sequences. It should have taken many daysof finicky work by technicians at the Pentagon before the originallybroadcast picture could be seen and the sound interpreted. But aplay-back recorder named Al, and a picture-unscrambler named Gus were inclosed-circuit relationship with Betsy. She received the broadcast andthey unscrambled the sound and vision parts of it immediately. 

The translated broadcast, as Gus and Al presented it, was calculated toput the high brass of the defense forces into a frenzied tizzy. Theanguished consternation of previous occasions would seem like very calmcontemplation by comparison. The high brass of the armed forces shouldgrow dizzy. Top-echelon civilian officials should tend to talkincoherently to themselves, and scientific consultants--biologists inparticular--ought to feel their heads spinning like tops. 

The point was that the broadcast had to be taken seriously because itcame from nowhere. There was no faintest indication of any signaloutside of Betsy's sedately gray-painted case. But Betsy was not makingit up. She couldn't. There was a technology involved which required themost earnest consideration of the message carried by it. 

And this broadcast explained the danger from which the alleged futurewished to rescue its alleged past. A brisk, completely deracializedbroadcaster appeared on Gus's screen. 

In clipped, oddly stressed, but completely intelligible phrases, heexplained that he recognized the paradox his communication represented. Even before 1972, he observed, there had been argument about what wouldhappen if a man could travel in time and happened to go back to anearlier age and kill his grandfather. This communication was aninversion of that paradox. The world of 2180 wished to communicate backin time and save the lives of its great-great-great-grandparents so thatit--the world of 2180--would be born. 

Without this warning and the information to be given, at least half thehuman race of 1972 was doomed. 

In late 1971 there had been a mutation of a minor strain of_staphylococcus_ somewhere in the Andes. The new mutation thrived andflourished. With the swift transportation of the period, it had spreadpractically all over the world unnoticed, because it produced nosymptoms of disease. 

Half the members of the human race were carriers of the harmless mutated_staphylococcus_ now, but it was about to mutate again in accordancewith Gordon's Law (the reference had no meaning in 1972) and the newmutation would be lethal. In effect, one human being in two carried inhis body a semi-virus organization which he continually spread, andwhich very shortly would become deadly. Half the human race was bound todie unless it was instructed as to how to cope with it. Unless--

 * * * * *

Unless the world of 2180 told its ancestors what to do about it. Thatwas the proposal. Two-way communication was necessary for the purpose, because there would be questions to be answered, obscure points to beclarified, numerical values to be checked to the highest possible degreeof accuracy. 

Therefore, here were diagrams of the transmitter needed to communicatewith future time. Here were enlarged diagrams of individual parts. Theenigmatic parts of the drawing produced a wave-type unknown in 1972. Buta special type of wave was needed to travel beyond the three dimensionsof ordinary space, into the fourth dimension which was time. Thiswave-type produced unpredictable surges of power in the transmitter, wherefore at least six transmitters should be built and linked togetherso that if one ceased operation another would instantly take up thetask. 

 * * * * *

The broadcast ended abruptly. Betsy's screen went blank. The colonel wasnotified. A courier took tapes to Washington by high-speed jet. Life inResearch Establishment 83 went on sedately. The barracks and the marriedquarters and the residences of the officers were equipped withMahon-modified machines which laundered diapers perfectly, and with dialtelephones which always rang right numbers, and there were police-upmachines which took perfect care of lawns, and television receiverstuned themselves to the customary channels for different hours withastonishing ease. Even jet-planes equipped with Mahon units almostlanded themselves, and almost flew themselves about the sky in simulatedcombat with something very close to zest. 

But the atmosphere in the room in Communications was tense. 

"I think, " said Howell, with his lips compressed, "that this answers allyour objections, Graves. Motive--"

"No, " said Lecky painfully. "It does not answer mine. My objection isthat I do not believe it. "

"Huh!" said Sergeant Bellews scornfully. "O' course, you don't believeit! It's phoney clear through!"

Lecky looked at him hopefully. 

"You noticed something that we missed, Sergeant?"

"Hell, yes!" said Sergeant Bellews. "That transmitter diagram don't havea Mahon unit in it!"

"Is that remarkable?" demanded Howell. 

"Remarkable dumb, " said the sergeant. "They'd ought to know--"

The tall young lieutenant who earlier had fetched Sergeant Bellews toCommunications now appeared again. He gracefully entered the room whereBetsy waited for more broadcast matter. Her standby light flickered withsomething close to animation, and the similar yellow bulbs on Al and Gusresponded in kind. The tall young lieutenant said politely:

"I am sorry, but pending orders from the Pentagon the colonel hasordered this room vacated. Only automatic recorders will be allowedhere, and all records they produce will be sent to Washington withoutexamination. It seems that no one on this post has the necessaryclearance for this type of material. "

Lecky blinked. Graves sputtered:

"But--dammit, do you mean we can work out a way to receive a broadcastand not be qualified to see it?"

"There's a common-sense view, " said Sergeant Bellews oracularly, "and acrazy view, and there's what the Pentagon says, which ain't either. " Hestood up. "I see where I go back to my shop and finish rehabilitatin'the colonel's vacuum cleaner. You gentlemen care to join me?"

Howell said indignantly:

"This is ridiculous! This is absurd!"

"Uh-uh, " said Sergeant Bellews benignly. "This is the armed forces. There'll be an order makin' some sort of sense come along later. Meanwhile, I can brief you guys on Mahon machines so you'll be ready tostart up again with better information when a clearance order does comethrough. And I got some beer in my quarters behind the Rehab Shop. Comealong with me!"

He led the way out of the room. The young lieutenant paused to close thedoor firmly behind him and to lock it. A bored private, with side-arms, took post before it. The lieutenant was a very conscientious young man. 

But he did not interfere with the parade to Sergeant Bellews' quarters. The young lieutenant was very military, and the ways of civilians werenot his concern. If eminent scientists chose to go to Sergeant Bellews'quarters instead of the Officers Club, to which their assimilated rankentitled them, it was strictly their affair. 

 * * * * *

They reached the Rehab Shop, and Sergeant Bellews went firmly to astandby-light-equipped refrigerator in his quarters. He brought out beerand deftly popped off the tops. The icebox door closed quietly. 

"Here's to crime, " said Sergeant Bellews amiably. 

He drank. Howell sipped gloomily. Graves drank thoughtfully. Leckylooked anticipative. 

"Sergeant, " he said, "did I see a gleam in your eye just now?"

Sergeant Bellews reflected, gently shaking his opened beer-can with arotary motion, for no reason whatever. 

"Uh-uh, " he rumbled. "I wouldn't say a gleam. But you mighta seen aglint. I got some ideas from what I seen during that broadcast. I wannaget to work on 'em. Here's the place to do the work. We got facilitieshere. "

Howell said with precise hot anger:

"This is the most idiotic situation I have ever seen even in governmentservice!"

"You ain't been around much, " the sergeant told him kindly. "It happenseverywhere. All the time. It ain't even a exclusive feature of the armedforces. " He put down his beer-can and patted his stomach. "There's guyswho sit up nights workin' out standard operational procedures just tomake things like this happen, everywhere. The colonel hadda do what hedid. He's got orders, too. But he felt bad. So he sent the lieutenant totell us. He does the colonel's dirty jobs--and he loves his work. "

 * * * * *

He moved grandly toward the Rehab Shop proper, which opened off thequarters he lived in--very much as a doctor's office is apt to open offhis living quarters. 

"We follow?" asked Lecky zestfully. "You plan something?"

"Natural!" said Sergeant Bellews largely. 

He led the way into the Rehab Shop, which was dark and shadowy, and onlyvery dimly lighted by flickering, wavering lights of many machineswaiting as if hopefully to be called on for action. There were theshelves of machines not yet activated. Sergeant Bellews led the waytoward his desk. There was a vacuum cleaner on it, on standby. He put itdown on the floor. 

Lecky watched him with some eagerness. The others came in, Howell dourlyand Graves wiping his moustache. 

The sergeant considered his domain. 

"We'll be happy to help you, " said Lecky. 

"Thanks, " said the sergeant. "I'm under orders to help you, too, y'know. Just supposing you asked me to whip up something to analyze what Betsyreceives, so it can be checked on that it is a new wave-type. "

"Can you do that?" demanded Graves. "We were supposed to work onthat--but so far we've absolutely nothing to go on!"

The sergeant waved his hand negligently. 

"You got something now. Betsy's a Mahon-modified device. Every receiverthat picked up one of those crazy broadcasts broke down before it wasthrough. She takes 'em in her stride--especial with Al and Gus to helpher. Wouldn't it be reasonable to guess that Mahon machinesare--uh--especial adapted to handle intertemporal communication?"

"Very reasonable!" said Howell dourly. "Very! The broadcast said thatthe wave-type produced unpredictable surges of current. Ordinarymachines do find it difficult to work with whatever type of radiationthat can be. "

"Betsy chokes off those surges, " observed the sergeant. "With Gus and Alto help, she don't have no trouble. We hadn't ought to need to make anysix transmitters if we put Mahon-unit machines together for the job!"

"Quite right, " agreed Lecky, mildly. "And it is odd--"

"Yeah, " said the sergeant. "It's plenty odd mygreat-great-great-grandkids haven't got sense enough to do itthemselves!"

 * * * * *

He went to a shelf and brought down a boxed machine, --straight from thetop-secret manufactory of Mahon units. It had never been activated. Itsstandby light did not glow. Sergeant Bellews ripped off the carton andsaid reflectively:

"You hate to turn off a machine that's got its own ways of working. Buta machine that ain't been activated has not got any personality. So youdon't mind starting it up to turn it off later. "

He opened the adjustment-cover and turned something on. The standbylight glowed. Closely observed, it was not a completely steady glow. There were the faintest possible variations of brightness. But there wasno impression of life. 

Graves said:

"Why doesn't it flicker like the others?"

"No habits, " said the sergeant. "No experience. It's like a newbornbaby. It'll get to have personality after it's worked a while. But notnow. "

He went across the shop again. He moved out a heavy case, and twistedthe release, and eased out a communicator of the same type--Mark IV--asBetsy back in the Communications room. Howell went to help him. Gravestried to assist. Lecky moved other things out of the way. They werehighly eminent scientists, and Metech Sergeant Bellews was merely anon-commissioned officer in the armed forces. But he happened to havespecialized information they had not. Quite without condescension theyaccepted his authority in his own field, and therefore his equality. Ascivilians they had no rank to maintain, and they disagreed with eachother--and would disagree with the sergeant--only when they knew why. Which was one of the reasons why they were eminent scientists. 

Sergeant Bellews brought out yet another box. He unrolled cables. Heselected machines whose flickering lights seemed to bespeak eagerness tobe of use. He coupled them to the newly unboxed machines, whose lightswere vaguely steady. 

"Training cables, " he said over his shoulder. "You get one machineworking right, and you hook it with another, and the new machine kindalearns from the old one. Kinda! But it ain't as good as real experience. Not at first. "

 * * * * *

Presently the lights of the newly energized machines began to waver insomewhat the manner of the ready-for-operation ones. But they did notgive so clear an impression of personality. 

"Look!" said Sergeant Bellews abruptly. "I got to check with you. Themore I think, the more worried I get. "

"You begin to believe the broadcasts come from the future?" demandedGraves. "And it worries you? But they do not speak of Mahon units--"

"I don't care where they come from, " said the sergeant. "I'm worryin'about what they are! The guy in the broadcast--not knowing Mahonunits--said we'd have to make half a dozen transmitters so they'd takeover one after another as they blew out. You see what that means?"

Lecky said crisply:

"You pointed it out before. There is something in the wave-typewhich--you would say this, Sergeant!--which machines do not like. Isthat the reasoning?"

"Uh-uh!" The sergeant scowled. "Machines work by the golden rule. Theytry to do unto you what they want you to do unto them. Likes an'dislikes don't matter. I mean that there's something about thatwave-type that machines _can't_ take! It busts them. If it sort ofexplodes surges of current in 'em--Look! Any running machine is adynamic system in a object. A jet-plane operating is that. So's awater-spout. So's a communicator. But if you explode surges of heavycurrent in a dynamic system in a operating machine--things get messedup. The operating habit is busted to hell. I'm saying that if thiswave-type makes crazy surges of current start up--why--if the surgesare strong enough they'll bust not only a communicator but a jet-plane. Or a water-spout. Anything! See?"

 * * * * *

Lecky blinked and suddenly went pale. 

"But, " said Howell reasonably, "you said that Betsy handled it. Especially well when linked with other Mahon machines. "

"Yeah, " said the sergeant. 

"I think, " observed Graves jerkily, "that you are preparing newmachines, without developed--personalities, because you think that ifthey make this special-type wave they'll be broken. "

"Yeah, " said the sergeant, again. "The signal Betsy was amplifyin'coulda been as little as a micro-micro-watt. At its frequency an' type, she'd choke it down if it was more. But even a micro-micro-watt botheredBetsy until she got Al and Gus to help. She was fair screamin' forsomebody to come help her hold it. But the three of them done allright. "

Howell conceded the point. 

"That seems sound reasoning. "

"But you don't broadcast with a micro-micro-watt. You use a hell of alot more power than that! The transmitter the guy in the screen said tomake was a twenty-kilowatt job. Not too much for a broadcast of sinewaves, but a hell of a lot to be turned loose, in waves that have Betsyhollerin' at the power she was handlin'!"

"It might break even the Mahon machines in this installation?" demandedHowell. 

"You're gettin' warm, " said the sergeant. 

Graves said:

"You mean it might break all operating communicators in a very largearea?"

"You're gettin' hot, " said the sergeant grimly. 

Lecky wetted his lips. 

"I think, " he said very carefully, "that you suspect it is a wave-typewhich will break any dynamic system, in any sort of object a dynamicsystem can exist in. "

"Yeah, " said the sergeant. He waited, looking at Lecky. 

"And, " said Lecky, "not only operating machines are dynamic systems. Living plants and animals are, too. So are men. "

"That's what I'm drivin' at, " said Sergeant Bellews. 

"So you believe, " said Lecky, very pale indeed, "that we have been giventhe circuit-diagram of a transmitter which will broadcast a wave-typewhich destroys dynamic systems--life as well as the operation ofmachines. Persons--in the future or an alien creature in a space-ship, or perhaps even the Compubs--are furnishing us with designs fortransmitters of death, to be linked together so that if one fails theothers will carry on. And they lure us to destroy ourselves by lyingabout who they are and what they propose. "

"They're lyin', " said the sergeant. "They say they're in the future andthey don't know a thing about Mahon units. Else they'd use 'em. "

Lecky wetted his lips again. 

"And--if they are not in the future, they are trying to get us todestroy ourselves because that would be safer and surer than trying todestroy us by--say--transmitters of death dropped upon us by parachute. Yet if we do not destroy ourselves, they will surely do that. "

"If we don't bump ourselves off, it'll be because we got wise, "acknowledged the sergeant. "If we get wise, we could bump them off byparachute-transmitter. So they'll beat us to it. They'll have to!"

"Yes, " said Lecky. "They'll have to. It has always been said that adeath-ray was impossible. This would be a death-broadcast. If we do notbroadcast, they will--whoever they are. It is--" He smiled mirthlesslyat the magnitude of his understatement. "It is urgent that we dosomething. What shall we do, Sergeant?"

 * * * * *

A squadron of light tanks arrived at Research Installation 83 thatafternoon, with a shipment of courier motorcycles. They had beenequipped with Mahon units and went to the post to be trained. 

The Pentagon was debating the development of a Mahon-modified guidedmissile, and a drone plane was under construction. But non-militaryitems also arrived for activation and test. Automatic telephoneswitching systems, it appeared, could be made much simpler if they couldbe trained to do their work instead of built so they couldn't help it. 

Passenger-cars other than jeeps showed promise. It had long been knownthat most accidents occurred with new cars, and that ancient jalopieswere relatively safe even in the hands of juvenile delinquents. It wascredible that part of the difference was in the operating habits of thecars. 

It appeared that humanity was upon the threshold of a new era, in whichthe value of personality would reappear among the things taken forgranted. Strictly speaking, of course, Mahon machines were not persons. But they reflected the personalities of their owners. It might againseem desirable to be a decent human being if only because machinesworked better for them. 

But it would be tragic if Mahon machines were used to destroy humankindwith themselves! Sergeant Bellews would have raged at the thought oftraining a Mahon unit to guide an atom bomb. It would have to be--in afashion--deceived. He even disliked the necessity he faced thatafternoon while a courier winged his way to the Pentagon with thetop-secret tapes Betsy and Al and Gus had made. 

The Rehab Shop was equipped not only to recondition machines but to testthem. One item of equipment was a generator of substitute broadcastwaves. It could deliver a carrier-wave down to half a micro-micro-wattof any form desired, and up to the power of a nearby transmitter. It wasvery useful for calibrating communicators. But Sergeant Bellews modifiedit to allow of variations in type as well as frequency and amplitude. 

"I'm betting, " he grunted, "that there's different sorts of thewave-type those guys want us to broadcast. Like there's a spectrum ofvisible light. If we were color-blind and yellow'd bust things, they'dtransmit in red that we could see, and they'd tell us to broadcastsomething in yellow that'd wipe us out. And we wouldn't have senseenough not to broadcast the yellow, because we wouldn't know thedifference between it and red until we did broadcast. Then it'd be toolate. "

Howell watched with tight-clamped jaws. He had committed himself to theauthenticity of the broadcasts claiming to be from a future time. Now hewas shaken, but only enough to admit the need for tests. Graves satunnaturally still. Lecky looked at Sergeant Bellews with a peculiarlytranquil expression on his face. 

"Only, " grunted the sergeant, "it ain't frequency we got to figure, buttype. Nobody hardly uses anything but sine waves for communication, butI got to make this gadget turn out a freak wave-type by guess and golly. I got a sort of test for it, though. "

 * * * * *

He straightened up and connected a cable from the generator to the MarkIV communicator which was a factory twin of Betsy. 

"I'm gonna feed this communicator half a micro-micro-watt of stuff likethe broadcast--I think, " he announced grimly. "I saw the diagrams of thetransmitters they want us to make. I'm guessing the broadcast-wave theyuse is close to it but not exact. Close, because it's bad for machines. Not exact, because they're alive while they use it. I hope I don't hitanything on the nose. Okay?"

Lecky said gently:

"I have never been more frightened. Go ahead!"

Sergeant Bellews depressed a stud. The communicator's screen lighted upinstantly. It was receiving the generator's minute output and acceptedit as a broadcast. But the signal was unmodulated, so there was no imagenor any sound. 

 * * * * *

The communicator's standby light flickered steadily. 

Sergeant Bellews adjusted a knob on the generator. The communicator'sstandby flicker changed in amplitude. Bellews turned the knob back. Headjusted another control. The standby light wavered crazily. 

Graves said nervously:

"I think I see. You are trying to make this communicator react as Betsydid. When it does, you will consider that your generator is creating awave like the broadcasts from nowhere. "

"Yeah, " said Bellews. "It ain't scientific, but it's the best I can do. "

He worked the generator-controls with infinite care. Once thecommunicator's standby light approached sine-wave modulation. He hastilyshifted away from the settings which caused it. He muttered:

"Close!"

Then, suddenly, the communicator's lamp began to waver in anextraordinary, hysterical fashion. Sergeant Bellews turned down thevolume swiftly. He wiped sweat off his forehead. 

"I--I think I got the trick, " he said heavily. "It's a hell of awave-type! Are you guys game to feed it into this communicator's outputamplifier?"

"I have six sets of cold chills running up and down my spine, " saidLecky. "I think you should proceed. "

Howell said angrily:

"It's got to be tried, hasn't it?"

"It's got to be tried, " acknowledged Sergeant Bellews. 

He shifted the generator's cable from the communicator's input to thefeed-in for preamplified signal. The communicator's screen went dark. It no longer received a simulated broadcast signal. It was nowsignalling--calling. But the instant the new signal started out, thestandby light flickered horribly. Sergeant Bellews grimly plugged inother machines--to the three scientists they looked like duplicates ofGus and Al--to closed-circuit relationship with Betsy's twin. Thestandby light calmed. 

"Now we test, " he said grimly. "Got a watch?"

Lecky extended his wrist. 

"Watch it, " said Sergeant Bellews. 

He stepped up the output. 

"My watch has stopped, " said Lecky, through white lips. 

Graves looked at his own watch. He shook it and held it to his ear. Helooked sick. Howell growled and looked at his own. 

"That wave stops watches, " he admitted unwillingly. 

"But not Mahon machines easy, " said Sergeant Bellews heavily, "and notus. There was almost three micro-micro-watts goin' out then. That'sthree-millionths of a millionth of a ampere-second at one volt. We--"

 * * * * *

His voice stopped, as if with a click. The screen of Betsy'sfactory-twin communicator lighted up. A man's face peered out of it. Hewas bearded and they could not see his costume, but he was frightened. 

"_What--what is this?_" cried his voice shrilly from the speakers. 

Sergeant Bellews said very sharply:

"Hey! You ain't the guy we've been talking to!"

The screen went dark. Sergeant Bellews put his hand over the microphoneopening. He turned fiercely upon the rest. 

"Look!" he snapped. "We were broadcastin' their trick wave--the wavethey used to talk to us! And they picked it up! But they weren'texpectin' it! They were set to pick up the wave they told us totransmit! See? That guy'll come back. He's got to! So we got to playalong! He'll want to find out if we got wise and won't broadcastourselves to death! If he finds out we know what we're doin', they'llparachute a transmitter down on us before we can do it to them! Back meup! Get set!"

He removed his hand from the microphone. 

"Callin' 2180!" he chattered urgently. "Calling the guy that justcontacted us! Come in, 2180! You're not the guy we've been talking to, but come in! Come in, 2180!"

Howell said stridently:

"But if that's 2180, how'd we parachute--". 

Lecky clapped a hand over his mouth with a fierceness surprising in sosmall a man. He whispered desperately into Howell's ear. Graves absurdlybegan to bite his nails, staring at the communicator-screen. SergeantBellews continued his calling, ever more urgently. 

His voice echoed peculiarly in the Rehab Shop. It seemed suddenly aplace of resonant echoes. All the waiting, repaired, orto-be-rehabilitated machines appeared to listen with interest whileSergeant Bellews called:

"Come in, 2180! We been trying to reach you for a coupla weeks! We gotsomebody else instead of you, and they been talkin' to us, and they saythat they're 3020 instead of 2180, but we've got to contact you! Theydon't know anything about that germ that's gonna mutate and bump us off!It's ancient history to them. We got to reach you! Come in, 2180!"

The flickering yellow lights of the machines wavered as if all thequasi-living machines were listening absorbedly. The Rehab Shop was fullof shadows. And Sergeant Bellews sat before the dark-screenedcommunicator with sweat on his face, calling cajolingly to nothingnessto come in. 

After five minutes the screen grew abruptly bright again. The brisk, raceless broadcaster of the earlier broadcast--not the bearded man--cameback. He forced a smile:

"_Ah! 1972! At last you reach us! But we did not hope you could makeyour transmitters so soon!_"

"We tried to analyze your wave, " said Sergeant Bellews, with everyappearance of feverish relief, "but we only got it approximate. We triedcallin' back with what we got, and we got through time, all right, butwe contacted some guys in 3020 instead of you! We need to talk toyou!--Can you give me the stuff about that bug that's gonna wipe outhalf of us? Quick? I got a recorder goin'. "

 * * * * *

The completely uncharacterizable man in the screen forced a secondsmile. He held something to his ear. It would be a tiny sound-receiver. Obviously the contact in time or place or nowhere was being viewed byothers than the one man who appeared. He was receiving instructions. 

"_Ah!_" he said brightly, "_but now that you have the contact, you willnot lose it again! Leave your controls where they are, and our learnedmen will tell your learned men all that they need to know. But--3020?You contacted 3020? That is not in our records of your time!_"

He listened again to the thing at his ear. His expression becamesuddenly suspicious, as if someone had ordered that as well as the wordswhich came next. 

"_We do not understand how you could contact a time a thousand yearsbeyond us. It is possible that you attempt a joke. A--a kid, as youwould say. _"

 * * * * *

Sergeant Bellews beamed into the screen which so remarkably functionedas a transmitting-eye also. 

"Hell!" he said cordially. "You know we wouldn't kid you! You or ourgreat-great-great-grandchildren! We depend on you! We got to get you totell us how not to get wiped out! In 3020 the whole business isforgotten. It's a thousand years old, to them! But they're passin' backsome swell machinery--"

He turned his head as if listening to something the microphone could notpick up. But he looked appealingly at Lecky. Lecky nodded and movedtoward the communicator. 

"Look!" said Sergeant Bellews into the screen. "Here's Doc Lecky--one ofour top guys. You talk to him. "

He gave his seat to Lecky. Out of range of the communicator, he moppedhis face. His shirt was soaked through by the sweat produced by thestress of the past few minutes. He shivered violently, and then clampedhis teeth and fumbled out sheets of paper. He beckoned to Graves. Gravescame. 

"We--we got to give him a doctored circuit, " whispered Sergeant Bellewsdesperately, "and it's got to be good--an' quick!"

Graves bent over the paper on which the sergeant dripped sweat. Thesergeant murmured through now-chattering teeth what had to be devised, and at once. It must be the circuit-diagram for a transmitter to begiven to the man whose face filled the screen. The transmitter must beof at least twenty-kilowatt power. It must be such a circuit as nobodyhad ever seen before. 

It must be convincing. It should appear to radiate impossibly, or todestroy energy without radiation. But it must actually produce abroadcast signal of this exotic type--here the sergeant described withshaky precision the exact constants of the wave to be generated--and thebroadcaster from nowhere must not be able to deduce those constants orthat wave-type from the diagram until he had built the transmitter andtried it. 

"I know it can't be done!" said the sergeant desperately. "I know itcan't! But it's gotta be! Or they'll parachute a transmitter down on ussure. "

Graves smiled a quick and nervous smile. He began to sketch a circuit. It was a wonderful thing. It was the product of much ingenuity andmeditation. It had been devised--by himself--as a brain-teaser for theamusement of other high-level scientific brains. Mathematicianszestfully contrive problems to stump each other. Specialists in thehigher branches of electronics sometimes present each other withdiagrammed circuits which pretend to achieve the impossible. The problemis to find the hidden flaw. 

Graves deftly outlined his circuit and began to fill in the details. Ostensibly, it was a circuit which consumed energy and producednothing--not even heat. In a sense it was the exact opposite of aperpetual-motion scheme, which pretends to get energy from nowhere. Thiscircuit pretended to radiate energy to nowhere, and yet to get rid ofit. 

 * * * * *

Presently Lecky could be heard expostulating gently:

"But of course we are willing to give you the circuit by which wecommunicate with the year 3020! Naturally! But it seems strange that yoususpect us! After all, if you do not tell us how to meet the danger yourbroadcasts have told of, you will never be born!"

Sergeant Bellews mopped his face and moved into the screen's field ofvision. 

"Doc, " he said, laying a hand on Lecky's arm. "Doc Graves is sketchin'what they want right now. You want to come show it, Doc?"

Graves took Lecky's place. He spread out the diagram, finishing it as hetalked. His nervous, faint smile appeared as the mannerism ofembarrassment it was. 

"There can be no radiation from a coil shaped like this, " he saidembarrassedly, "because of the Werner Principle. .. . Yet on examination. .. Input to the transistor series involves . .. Energy must flow . .. And when this coil. .. . "

His voice flowed on. He explained a puzzle, presenting it diffidently ashe had presented it to other men in his own field. Then he had beenplaying--for fun. Now he played for perhaps the highest stakes thatcould be imagined. 

He completed his diagram and, smiling nervously, held it up to thecommunicator-screen. It was instantly transmitted, of course. Tonowhere. Which was most appropriate, because it pretended to be thediagram of a circuit sending radiation to the same place. 

 * * * * *

The face on the screen twitched, now. The hand with the tiny earphonewas always at the ear of the man on the screen, so that he plainly didnot speak one word without high authority. 

"_We will--examine this_, " he said. His voice was a full two toneshigher than it had been. "_If you have been--truthful we will give youthe information you wish_. "

_Click!_ The screen went dark. Lecky let out his breath. SergeantBellews threw off the transmission switch. He began to shake. Howellsaid indignantly:

"When I make a mistake, I admit it! That broadcast isn't from thefuture! If it hadn't been a lie, he'd have known he had to tell us whatwe wanted to know! He couldn't hold us up for terms! If he let us die hewouldn't exist!"

"Y-yeah, " said Sergeant Bellews. "What I'm wonderin' is, did we foolhim?"

"Oh, yes!" said Graves, with diffident confidence. "I don't know butthree men in the world who could find the flaw in that circuit. " Hesmiled faintly. "But it radiates all the energy that's fed into it. " Heturned to Sergeant Bellews. "You gave me the constants of a wave youwanted it to radiate. I fixed it. It will. But why that specialtype--that special wave?"

Sergeant Bellews pulled himself together. 

"Because, " he said grimly, "that was the wave they wanted us tobroadcast. What I'm hoping is that you gave 'em a transmitter to doexactly the same thing as the one they designed for us. If they'refooled, they'll broadcast the wave they told us to broadcast. If itbusts machines, it'll bust their machines. If it stops all dynamicsystems dead--includin' men--they'll be stopped dead, too. " Then helooked from one to another of the three scientists, each one reacting inhis own special way. "Personally, " said Sergeant Bellews doggedly, "I'mgoin' to have a can of beer. Who'll join me?"

 * * * * *

The world wagged on. The automatic monitors in Communications Centerreported that another broadcast had been received by Betsy andundoubtedly unscrambled by Al and Gus, working as a team. The reportedbroadcast was, of course, an interception of the two-way talk from theRehab Shop. 

The tall young lieutenant, working with his eyes kept conscientiouslyshut, extracted the tapes and loaded them in a top-security briefcase. Asecond courier took off for Washington with them. There a certified, properly cleared major-general had them run off, and saw and heard everyword of the conversation between the Rehab Shop and--nowhere. He howledwith wrath. 

Sergeant Bellews went into the guardhouse while plane-loads ofinterrogating officers flew from Washington. Howell and Graves and Leckywent under strict guard until they could be asked some thousands ofvariations of the question, "Why did you do it?" The high brass quiveredwith fury. They did not accept decisions made at non-commissioned-officerlevel. 

Communication with their great-great-great-grandchildren, theyconsidered, should have been begun with proper authority and underhigh-ranking auspices. They commanded that 2180 should immediately bere-contacted and properly authorized and good-faith conference begun allover again. The only trouble was that they could get no reply. 

The dither was terrific and the tumult frantic. When, moreover, evenBetsy remained silent, and Al and Gus had nothing to unscramble, thehigh brass built up explosive indignation. But it was confined totop-security levels. 

The world outside the Pentagon knew nothing. Even at ResearchInstallation 83 very, very few persons had the least idea what had takenplace. The sun shone blandly upon manicured lawns, and the officers'children played vociferously, and washing-machines laundered diaperswith beautiful efficiency, and vacuum cleaners and Mahon-modified jeepsperformed their functions with an air of enthusiastic contentment. Itseemed that a golden age approached. 

It did. There were machines which were not merely possessions. Mahon-modified machines acquired reflections of the habits of thefamilies which used them. An electric icebox acted as if it took aninterest in its work. A vacuum cleaner seemed uncomfortable if it didnot perform its task to perfection. It would seem as absurd to exchangean old, habituated family convenience as to exchange a member of thefamily itself. Presently there would be washing-machines cherished fortheir seeming knowledge of family-member individual preferences, andpersonal fliers respected for their conscientiousness, and one wouldrelievedly allow an adolescent to drive a car if it were one of provenexperience and sagacity. .. . 

 * * * * *

The life of an ordinary person would be enormously enriched. AMahon-modified machine would not even wear out. It took care of its ownlubrication and upkeep--giving notice of its needs by the behavior ofits standby-lamp. When parts needed replacement one would feel concernrather than irritation. There would be a personal relationship with themachines which so faithfully reflected one's personality. 

And the machines would always, always, always act toward humansaccording to the golden rule. 

But meanwhile the Rehab Shop was taken over by officers of rank. Theytried frantically to resume the communication that had been broken off. Suspecting that Sergeant Bellews had shifted controls, they essayed toshift them back. The communicator which was Betsy's factory twin wentinto sine-wave standby-modulation, and suddenly smoked all over and waswrecked. The wave-generator went into hysterics and produced nothingwhatever. Then there was nothing to do but pull Sergeant Bellews out ofthe clink and order him to do the whole business all over again. 

"I can't, " said Sergeant Bellews indignantly. "It can't be done. Thoseguys are busy buildin' a transmitter according to the diagram Doc Gravesgave them. They won't pay no attention to anything until they'd tried tochat with their great-great-great-grand-children in 3120. They werephonys, anyhow! Pretendin' to be in 2180 and not knowin' what Mahonunits could do!"

Lecky and Graves and Howell were even less satisfactory. They couldn'tpretend even to try what the questioning-teams from the Pentagon wantedthem to do. And Betsy remained silent, receiving nothing, and Gus and Alwaited meditatively for something to unscramble, and nothing turned up. 

And then, at 3:00 P. M. Greenwich mean time, on August 9, 1972, nearlyevery operating communicator in the fringe of free nations around theterritory of the Union of Communist Republics--all communicators blewout. 

There were only four men in the world who really knew why--SergeantBellews and Lecky and Graves and Howell. They knew that somewhere behindthe Iron Curtain a twenty-kilowatt transmitter had been turned on. Itproduced a wave of the type and with the characteristics that would havebeen produced by a transmitter built from the diagram sent through Betsyand Al and Gus for people in the United States to build. Obviously, ithad been built from Graves' diagram broadcast to somewhere else and itbroadcast what the United States had been urged to broadcast. 

 * * * * *

It blew itself out instantly, of course. The wave it produced would stopany dynamic system at once, including its own. But it hit Stockholm andtraffic jammed as the dynamic systems of cars in operation weredestroyed. In Gibraltar, the signal-systems of the Rock went dead. Allaround the fringe of the armed Communist republics machines stopped andcommunications ended and very many persons with heart conditions diedvery quietly. Because their dynamic systems were least stable. Buthealthy people--like Mahon-modified machines--had great resistance . .. Outside the Iron Curtain. 

There was, though, almost a vacuum of news and mechanical operations atthe rim of a nearly perfect circle some four thousand miles in diameter, whose center was in a Compub research installation. 

It was very bad. Such a panic as had never been known before swept thefree world. Some mysterious weapon, it was felt, had been used tocripple those who would resist invasion, and the Compub armed forceswould shortly be on the march, and Armageddon was at hand. The freeworld prepared to die fighting. 

But war did not come. Nothing happened at all. In three days there weresketchy communications almost everywhere outside that monstrous circleof silence. But nothing came out of that circle. Nothing. 

In two weeks, exploring parties cautiously crossed the barbed-wirefrontier fences to find out what had happened. Those who went farthestcame back shaken and sick. There were survivors in the Compubs, ofcourse. Especially near the fringes of the circle. There were somemillions of survivors. But there was no longer a nation to be called theUnion of Communist Republics. There were only frightened, starvingpeople trudging blindly away from cities that were charnel-houses andmachines that would not run and trees and crops and grasses that werestark dead where they stood. It would be a long time before anybodywould want to cross those lifeless plains and enter the places whichonce had been swarming hives of homes and people. 

 * * * * *

And presently, of course, Sergeant Bellews was let out of theguardhouse. He could not be charged with any crime. Nor could Graves norLecky nor Howell. They were asked, confidentially, to keep their mouthsshut. Which they would have done anyhow. And Sergeant Bellews was askedwith reluctant respectfulness, just what he thought had really happened. 

"Some guys got too smart, " he said, fuming. "A guy that'll broadcast awave that'll wreck machines . .. I haven't got any kinda use for him!Dammit, when a machine treats you accordin' to the golden rule, yououghta treat it the same way!"

There were other, also-respectful questions. 

"How the hell would I know?" demanded Sergeant Bellews wrathfully. "Itcoulda been that we did make contact with 2180, and they were smart an'told the Compubs to try out what we told 'em. But I don't believe it. Itcoulda been a kinda monster from some other planet wanting us wiped out. But he learned him a lesson, if he did! And o' course, it coulda beenthe Compubs themselves, trying to fool us into committing suicide sothey'd--uh--inherit the earth. I wouldn't know! But I bet there ain'tany more broadcasts from nowhere!"

He was allowed to return to the Rehab Shop, and the flickering standbylights of many Mahon-modified machines seemed to glow more warmly as hemoved among them. 

And he was right about there not being any more broadcasts from nowhere. 

There weren't. 

Not ever. 

THE END