The Imagination Trap
                                               ONE

Professor Carl Diepenstrom, Director of Tau Research Corporation, switched off the
intercom.
      “Well, at least he’s come to see us, Paul.”
      Paul Porter nodded. “I thought he would. Eric Brevis can’t resist the lure of curiosity any
more than we can. In fact, if we can score with him, it will be on that very point.”
      “I see.” Diepenstrom raised his large and greying head and studied Porter seriously for a
moment or two. “And you still think it vitally necessary that we go through with this project,
Paul?”
      “You know it is. It’s the only chance we have. We can’t continue with the present research
line. It isn’t humanitarian, and it isn’t giving us a glimpse of a coherent pattern. Besides which,
you know how the Government’s attitude is hardening.”
      “Yes, I know it,” said Diepenstrom gravely. “And that’s the reason I’ve backed you as far as I
have. I can’t see any practical alternative. But I’d be happier if it didn’t have to be you who
went out there. Tau Research can’t afford to lose you, Paul.”
      “There won’t be any Tau Research if this project folds. Anyway, I don’t think the risk will
be too great—not if we can persuade Eric Brevis to join the team.”
      “You think a great deal of Dr Brevis, don’t you?”
      “I do. He has an intuitive understanding of the irrational, and that can be a prime factor for
survival under extreme Tau conditions. With him on the team we have a very real chance of
making a breakthrough.”
      “Very well,” said Diepenstrom. “If you want Dr Brevis, you shall have him. But you’d better
leave the interview to me. It may just be that he isn’t very willing to offer his life for
somebody else’s cause. In which case he will have to be . . . ah! . . . persuaded.”

As the psychologist entered the room, Diepenstrom rose in greeting.
      “Dr Brevis, thank you for coming.”
      Brevis seated himself carefully and took a cigar from the offered box. “Being in receipt of
such an intriguing communication, I could scarcely have refused.”
      Diepenstrom repressed a mischievous smile. “That was, shall we say, contrived. Curiosity
is a force far more potent than most people allow.”
      Brevis studied the Director’s face carefully for a moment. “True,” he said. “Though I don’t
think you asked me here just to discuss the psychology of curiosity.”
      “Indeed not. I wanted to discuss the possibility of death.”
      “Whose death—yours or mine?”
      “Yours.”
      Brevis exhaled sharply. “I suppose there’s some sense in this cryptic nonsense?”
      “There is indeed, my dear Doctor, and shortly I’ll tell you what it is. But first let me
enquire how much you know about Tau?”
      “Not very much. I know it’s a system in which solid bodies are resonated in such a way
that their atoms can pass through the spaces in the atomic structure of other solid bodies. I
know you use the method for transport, bringing the big Tau ships to resonance and then
driving them through the earth by the shortest mean path to their destination.”
      “Go on,” said Diepenstrom.
      “I know also that in its resonant state such a ship passes into an inter-atom domain called
Tau-space which is incongruent both physically and psychologically with conditions existing
in normal space.”
      “That will do for the moment,” said Diepenstrom. “I recall that you were concerned with
Paul Porter on the epic voyage of the old Lambda I Tau raft. I also recall that the impact of
some of the things you discovered on that journey caused a radical re-thinking of some major
portions of the Tau concept. I put it to you, Dr Brevis, that this is a remarkable record for one
who claims very little knowledge of Tau techniques.”
      “Suppose we come to the point,” said Brevis abruptly.
     “I was just going to,” said Diepenstrom. “Does the phrase deep-Tau mean anything to you?”
     “No.”
     “Then I’ll tell you. Deep-Tau is the Tau-space analogue of conventional deep space. We
are actively researching into the possibility of achieving interstellar spaceflight by travelling
in the Tau-space analogue.”
     “I don’t see . . .” said Brevis.
      “Let me finish first, please. Now, deep-Tau as an alternative to conventional spaceflight
promises some remarkable advantages in simplified technique. Indeed, it may be the only
technique to make star travel possible. Superficially, deep-Tau travel would appear to be
easier than terrestrial Tau work. Unfortunately there are a number of impossible and irrational
reasons why this is not so.”
     “I fail to see,” said Brevis, “what all this has to do with me.”
      “A great deal. The present pattern of Tau research consists of sending manned telemetry
probes into deep-Tau. We’ve sent some twenty-four to date. Some have returned and some
haven’t, but each has piled paradox on paradox—and each has cost the life of the probe pilot.
Now we’re approaching our last chance. If we fail, the Government will probably close down
our activities completely. Such an action would be a setback to this research from which it
might never recover.”
     “So?”
     “Paul Porter wants to take a four-man vessel fitted out as a laboratory into deep-Tau, and
he wants you to go with him. It’s my job to persuade you to go, while at the same time leaving
you in no doubt that to do so is tantamount to committing suicide.”
      “So that’s it! I refuse, of course. I still have the scars to show from the last time Paul Porter
took me into Tau.”
      “I have a contract here on which you can write your own price for one successful
deep-Tau vector.”
      “No, Professor. If Paul wants to seek an anguished grave in the corner of some dark and
twisted hypothetical continuum, that is his own affair. I’ve no such ambition.”
     “A fair statement, Dr Brevis. I appreciate your position. Faced with the same situation, I
should probably adopt a similar standpoint. Let me thank you again for coming, and apologize
for wasting your time.”
     Brevis watched him narrowly for a moment. “What are you up to, you old fox? You aren’t
a man to accept defeat that easily.”
      Diepenstrom raised his ponderous head. His smile was a mere ghost haunting the corners
of his mouth.
     “Ah, yes! There was something else. I’m glad you reminded me. While you’re here I
wonder if you’d care to see some of our deep-Tau exhibits.”
      “Seeing the whole point of this interview seems to turn on this apparent afterthought, I
have no objection. But I warn you that nothing you can show me will make me change my
mind.”
     “Perish the thought, my dear Doctor. I merely wish to show you our little museum of
paradoxes. I think you’ll find them rather fascinating. Would you care to step this way?”

The vaults beneath Tau Research were olive-drab and vast in extent, and the footsteps of the
two men echoed hollowly down the steel and concrete corridors. Brevis had previously had
no idea that Government influence extended to the point of including armed servicemen
alongside Tau Corporation’s own formidable security force. The two men were checked and
counter-checked at each level and intersection with a meticulous care which placed a sinister
stamp on the ultimate importance of the project.
     Brevis smiled wryly. “If I have as much trouble getting into Heaven as we’ve had getting
into here, I don’t think I’ll bother.”
     “Don’t worry,” said Diepenstrom. “The qualifications for entry are somewhat
different—one might almost say mutually exclusive.”
     “That’s a rare piece of cynicism.”
     “Wait,” said the Director, “until you’ve seen what we have to show you. There are more
things in Heaven and on Earth than are dreamed of in your psychology.”
     They reached the appointed door, and Diepenstrom withdrew the bolts with a heavy
clatter and stood aside for the psychologist to enter.
     “This is one of the ten or so probe vessels which we have been able to recover. It came
back to us on an automatic-recall vector from deep-Tau, and it’s not the least of our
curiosities.”
     Brevis entered the room and walked around the exhibit, his face registering a melange of
fear and fascination.
     “What sort of trick is this?”
     “No trick, Doctor. Simply one of those things that we at Tau Research have had to learn to
live with.”
     “And the pilot?” Brevis asked at last the question he had been avoiding.
     “He came back alive but died in hospital. He was completely to scale with the craft. He
was desperately mad and measured exactly one and a quarter inches tall. Do you want to see
any more?”
     “Not just now. One has to learn to re-adjust.”
     “You’re not feeling ill, are you?”
     “No. I was just thinking what a remarkable character your pilot must have been.”
     “You’ve got beyond me there,” said Diepenstrom, with sudden interest. “What did you have
in mind, Doctor?”
     “I was reflecting that you sent him into a complex so vast that it doesn’t include the
limiting concept ‘universe’. The wonder to me is not that he came back minute, but that he
didn’t come back microscopic.”
     A trace of light flickered across Diepenstrom’s brow.
     “I think you’re on to something, Dr Brevis. Paul Porter was right. You do have an intuitive
understanding of the irrational. Won’t you have second thoughts about joining our team?”
     “Damn you, Diepenstrom! You’ve pushed the ball right into my court.”
     “I merely showed you the ball. You did the pushing.”
     “But you knew which way it would roll.”
     “Certainly. With the pitch inclined at an angle of forty-five degrees in the right direction, I
could scarcely miss. It’s what I call an imagination trap. Give an expert an outstanding
problem in his own field, and you have one of the most infallible mousetraps ever devised.
Now suppose we go upstairs and sign that contract?”
     “I still haven’t said I agree,” Brevis said.
     “No, but you will. You see, if you walk out now you’ll always be haunted by the vision of
the Tau probe vessel which came back only twenty-two inches long and with a pilot not as big
as your thumb. I don’t think a man with your imagination could live with himself with that
problem unresolved.”
“It would appear,” said Brevis, “that I am now working for Tau Corporation until death do us
part—unless I misread the small print at the bottom of the contract. Although, if I have your
intentions divined aright, that mayn’t be a very long-term prospect.”
     Porter turned with a smile from the drafting machine. “I take it that you have just
concluded an interview with Diepenstrom. He tends to induce that depressive attitude in
interviews. Anyway, glad to have you join the team, Eric. On the type of project we’re
planning we’re going to need all the expertise we can get.”
     “Even in psychology?”
      “Especially in psychology—and your own understanding of the irrational. Eric, we’re going
into a complex which doesn’t begin until a point way beyond where our physics ends—out
into a region from which nothing vaguely rational has ever been recovered. What happens to
things out in deep-Tau is completely beyond our experience. That’s why I feel a sight happier
to know you’re going to be alongside.”
     “I’m with you, Paul . . . although just now I’m damned if I can think of a convincing reason
why. What’s the big attraction about going into deep-Tau anyway?”
      “Because it’s there, I guess. Man isn’t built to live happily on the edge of the unknown. And
if we’re ever to get to the stars, then deep-Tau is the only possible route.”
     “Not spaceflight?”
      Porter was slightly amused. “Hardly. Unless there are some very radical changes in our
concept of normal physics, we don’t have either the engines or the power sources necessary
to make such a journey in man’s lifetime. And we probably never will have. Mass-energy
relationships alone rule that out quite firmly.”
      “You’ve just shattered my dream of the space age,” said Brevis.
      “Except for a ruinously expensive exploration of the Solar system, it never was more than
a dream,” said Porter.
     “But doesn’t that apply to deep-Tau travel also?”
      “Not completely. In Tau-space there are no gravitational gradients to overcome, and
mass-energy relationships and some aspects of Relativity don’t hold strictly true. Don’t ask me
to show you the maths, because we’re still trying to understand it ourselves, but Tau-space
provides us with a potential medium in which we can circumvent a lot of the physical
absolutes which make conventional interstellar spaceflight an impossibility. Even the speed
of light is no longer a limiting velocity.”
      “But aren’t the power requirements still prohibitive?”
     “They’re high, but they don’t climb to infinity or anything like. Even today it’s theoretically
possible to build a ship which could make a thirty-two light year round trip through deep-Tau
to Altair and back under its own power.”
     “Phew! I begin to see the attraction.”
      “Precisely,” said Porter. “If we can’t reach the stars via Tau-space then it’s doubtful if we
shall ever reach them. But standing in our way is a set of problems so imponderable that we
don’t know how to begin to start to solve them.”
      “How much do we know about these problems?”
      “Lamentably little. Apart from the monstrosities in the vaults which came back on
automatic-recall vectors, all our information is limited to transmitted verbal and telemetered
material gathered during the first few hours of a probe vector run—that is to say, before the
vessels achieved the speed of light.”
      “So the speed of light is a limiting velocity?”
      “Not in the usual sense. Neither is it a failure of communication due to Döppler effect.
This is something truly frightening in its implications.”
      “Go on!” Brevis said, noting the look in Porter’s eyes.
     “When the probe vessel reaches the velocity of light our receiver here at Tau Research
breaks down. The probe continues to transmit, but we can’t receive its signals.”
     “I don’t understand,” said Brevis.
     “Neither do we.” Porter’s face was haunted. “Their signal strength increases to such
proportions that the current actually fuses the terminal elements of our receiver. Millions of
amperes are involved.”
     “But how can that be?”
     “I don’t know. But the implications are terrifying. If we can receive such power over such
a distance . . . then what must have happened to the ship itself? Such a condition presupposes
that the ship’s transmitters are happily modulating beamed power equal to the output of a
pretty fair-sized star.”


                                              TWO

“Well, that’s the ship, Eric. We’re calling her Lambda II after Rorsch’s original Tau raft.”
      Brevis looked down. “And there the similarity ends,” he said.
      They were on the balcony of Tau Research’s main assembly shop, and below them the
huge vessel, running almost the length of the facility, returned the solid glint of flawlessly
polished metal. Even now a group of fitters was engaged in burnishing the plating with great
attention, against the possibility of its eventual emergence into the rays of some strange and
alien sun.
      “It looks more like a spaceship than a Tau craft,” said Brevis.
      “That’s effectively what it is—a spaceship built around the largest and most stable
Tau-spin generator we could find. We’ve made it capable of operating in either Tau or real
space environments in the hope that we may achieve the easy transposition from one to the
other. We’ve proved such a transposition is possible in vacuum without the necessity for a
grid.”
      “I’d no idea you were planning anything on this scale.”
      Porter shrugged. “It’s our last chance, Paul. Tau Corporation is staking everything on this
gamble. We’ve spent twenty-one and a half million on Lambda II so far—and it could have
been five times that much except that the Nuclear Energy Authority donated the reactor
design and provided the fuel. The Rorsch generator was diverted from a luxury Tau liner
already under construction, or we could easily have spent another three million on that.”
      Bevis looked slightly dazed. “And this type of money is readily available?”
      “A hundred times that, if necessary. The project is that important. The proof of the project
is whether we can go out into deep-Tau and come back alive. Any facility which might aid us
in doing just that is ours for the asking.”
      Brevis nodded. “If only we knew in advance what to ask for,” he said.
      Immediately below them now the four snow-white ceramic tubes of the thrust jets gave a
shrewd hint of the capacity of the drive reactor, cunningly contrived to conform to the
hindshape of the hull itself. Many large industrial cities had less power than this at their
disposal. Almost centrally along its length the hull bulged into a globe wherein was situated
the mammoth Rorsch generator, originally designed to induce Tau-spin in a luxury craft of
nearly a hundred times the mass displacement of its present charge.
      The front of the ship was blind, save for antennae and the scanning and sensing devices
feeding the instrumentation which had to serve in lieu of eyes. The only concession to the
need to physically observe was the blister atop the ship, which emerged through the heavy
shielding protecting the ship’s occupants from the unwelcome psychic molestations of the
raw Tau environment. Apart from that, the hull was featureless.
     “We’ll go in later,” said Porter. “First I want you to meet the rest of the team. I know
they’re very curious about you.”
     “Curious?”
     Porter smiled briefly. “I could have been forgiven for picking a cosmologist, a nuclear
physicist, or a radio-astronomer—in fact a man specializing in any of the hundred or so
branches of physical science with which we get involved in deep-Tau work. But when I
announced I was bringing in a far-out psychologist, reactions ranged from the incredulous to
the hostile.
     “The objections weren’t too serious, of course. We needed a qualified medic aboard, and
that factor plus your previous record in Tau made you the natural choice anyway. But Tau
pilots especially are somewhat sensitive of implied criticism of their mental balance. Not
unreasonably, I suppose, when we expect them to come to meaningful decisions in what is
essentially an irrational environment.”
     “I promise you I’ll tread lightly,” said Brevis.
     The others were already in the office when they arrived. Porter kept the introductions
brief. Sigmund Grus, fortyish, a Tau Research senior physicist, heavy, Germanic save in all but
accent. He was every inch an applied intellectual, with a rational solidity behind his thinking
which matched his frame.
     The second was Pat Driscoll, senior Tau test pilot. An altogether different character. In his
early thirties, he was nervous and apparently unsure of himself. Though his face registered his
thoughts on the trend of the conversation, he only once allowed himself to speak, and then did
so with such embarrassing over-emphasis of point that he confused himself in mid-sentence
and trailed back into pathetic silence.
     After two hours the meeting broke up, they having summarized for Brevis’ benefit the
duties and responsibilities of each man on the team. Brevis alone had no set duties. While the
others concerned themselves with the machines and mechanics of the trip, his concern was
solely with the functioning of the men.
     Afterwards Brevis and Porter went down to the ship. The psychologist had to familiarize
himself with the various equipments controlling the temperature, humidity and composition
of the ship’s atmosphere, and the devices provided to assist survival against various levels of
potential catastrophe. Also it was left to him to equip the tiny hospital room and operating
theatre, and to decide what medicaments and drugs should be carried. Porter showed him his
quarters and provided him with the necessary charts and layouts.
     “By the way, Eric, what do you make of the others?” Porter slipped the question in
apparently casually as they turned to leave, but there was no doubt it had been long in his
mind.
     Brevis shrugged. “I was going to take that up with you. I take it they were picked for their
specialities rather than their suitability for an exploratory voyage of this kind.”
     “Very much so. We don’t have any mental and physical supermen with sufficiently
advanced Tau knowledge, and it would take too long to train some. Therefore we
compromised. We took the most technically able men who also had practical Tau operating
experience, and threw in a full-time psychologist to balance the equation. Unorthodox, I
know, but it’s only one of the compromises we’ve had to make in getting a project like this off
the ground.”
     “Mm!” said Brevis. “Ordinarily the only man I’d recommend for a venture of this
magnitude would be yourself. Sigmund Grus is sound enough, but he’d be better left in his own
laboratory with his wife to meet him in the car. But I’m more than a little dubious about Pat
Driscoll. He’s a man who lives inside himself too much. I’d imagine his I.Q. is something quite
fantastic, but he’s introverted almost to the point of being unable to communicate. I certainly
can’t recommend exposing him to stressful situations. He’s a weak link, Paul.”
      “But he’s also the best and most experienced Tau pilot available. He has over a thousand
vector runs to his credit, many of them on unprogrammed exploratory runs. Take it from me,
Eric, there’s no pilot on Tau Corporation’s payroll better suited than Pat Driscoll to handle
this trip.”
     “I’ll take your word for it. But at least you can’t say you weren’t warned.”
      “Exactly what are you afraid of, Eric? Every man on this team has already proven his
capability of working and surviving under extreme Tau conditions. You can’t have a better
criterion than that.”
     “No, except that I suspect both you and I are already quite certain that the extremes of the
Tau-state influence aren’t going to be our greatest hazards. Else, Paul, why did you include as
your medic someone who was also a far-out psychologist?”

In the subsequent months of preparation the tension slowly mounted. Brevis had ample time
to observe its effect upon his fellow team members. He found nothing to make him revise his
original conclusions as to their psychological suitability, but he rapidly acquired a respect for
their technical competence. Sigmund Grus, particularly, impressed him with his detailed
understanding of the craft and all its installations.
     Two major landmarks measured the progress towards the final departure time. The first
was the bringing of the Lambda II’s reactor up to criticality, and the second was the successful
proving trial of the giant Rorsch Tau-spin generator. Then the only stage left was the towing of
the craft from the assembly shop to the adjoining bay where lay the immense Tau terminal grid
which would launch its charge into the unknowns of the deep-Tau continuum.
     When this operation too had been completed, the air of expectancy and tension rose like
a fever. Whether for success or disaster, the die was already cast. Any inherent faults and
shortcomings in the ship were both unknown and scarcely alterable. This was the machine, the
physics and mechanics of the project. From this point on the emphasis was very much on the
men.
     In the eighteen hours of countdown every conceivable item of instrumentation, control
and communication was re-checked, and double checked. The huge Rorsch generator, unstable
in standby state, responded magnificently on ready-state power, and gave every promise of a
fault-free operating condition. The reactor performance was well above specification, and the
ship computer had long been soundlessly exchanging its fantastic number sequences with its
communication counterpart in the Tau Research information centre.
     At two hours to take-off, the team had their final assembly. The atmosphere was so highly
charged emotionally that the image of the voyage had assumed epic proportions before it had
even begun, and Brevis signalled to Porter to close the hatches early to quieten the tension.
Their departure into such a radical unknown as deep-Tau was a psychological vortex which
those who experienced it would never quite forget.
     With the hatches closed and the occupants insulated from the outer activities except for
the electronic chatter of check and counter-check, the tension within the ship swiftly
subsided. It was replaced by an immediate sense of identity with the ship and its purpose.
Porter took the control room, Driscoll the blister. Grus, having re-run a check-out exercise on
the reactor, hastened to his beloved computer where the instrument data was being processed
into an endless electronic digest which could be all the world outside might ever know as to
their fate in deep-Tau.
     Brevis, his instrumentational chores completed, found himself suddenly at a loss, and
retired to his bunk to lay, half resting, mentally reviewing what he knew of the strengths and
weaknesses of his companions, and listening to their conversation on the intercom set.
     “Zero minus ten minutes.” Porter’s voice over the loudspeaker was a clear, precise,
ritualistic chant. Perfectly controlled. No sign yet that his subconscious had fully absorbed the
impact of the situation.
     “Tracking stations Pi and Sigma receiving our beam and locked on,” said Grus. Sigmund
Grus—his strength was that he probably never would perceive the deeper significance of the
situation. As the flesh served to cushion his body, so his technology cushioned his mind. But
pity him on the day when some inexorable reality leaned down to crush him.
     “Seventeen point nine times ten to the minus eleven. Sigmund, I’ll need help with the
tensor analysis.” That was Driscoll. His psyche knew where they were going . . . had known it
for a long time . . . had soaked itself in a little acid-pit of dread. But when your psyche has a
wound in it as deep and raw as his, you can’t bear to be far away from the possibility of death
for long. Nevertheless you can still leave sweat, grey upon the pillow.
     And himself? How much of the unknown could he take? No use to worry. The unknown
and the irrational was his speciality. His drugs had taken him through stranger exercises of the
mind than anything deep-Tau might have to offer. Perhaps.
     “Three minutes,” said Porter’s voice. “This will be a two-part take-off. We will adopt the
Tau state but remain on the grid until the computer has cleared the course co-ordinates. Eric,
if you want to do any preliminary work on the Tau phenomena you’d better join Pat in the
blister right away.”
      Brevis leaned to his microphone. “Check!”
      He made his way to the blister directly. Somewhere down the corridors as he walked, the
ship made a perfect transition from real space into Tau, becoming coexistent with the
molecules of the air which rushed in to fill the void it had left on the grid. But deep within the
ship the transition was indetectable. In the blister, beyond the screens, it would be different.
Very different. He halted before the heavy blister door and wiped the sweat from his palms.
The reaction of unshielded Tau influence with certain centres of the brain gave rise to
hallucinatory images so strong that they equated fairly well with all a man could ever know of
reality.
      He shouldered the door open, watching the telltales on the wall to give him an indication
of the position of the screens set mazeform to shield the emanations of the blister from the
ship. The room was dark, but three steps sufficed to place him in the maze and from there he
could proceed by fingertip location of the route. But as his head cleared the final screen he
again stopped, breathing heavily with part fear and part wonder.
     Although their spatial analogue was still the black iron of the grid in the confines of Tau
Research, nothing of this was visible. Instead, the blister seemed to be an island floating in
alarming isolation in the midst of a pink waste which was the characteristic image of the Tau
Gamma mode of resonance. But the knowledge of its origin in no way lessened its scope and
awesomeness. Here was space, limitless in a way no real-space panorama could ever be.
      Nothing was visible above or below, nor on any side, save for a shifting pink radiance
which had no apparent source and which closed around from all sides. Brevis knew this to be
subjective illusion, and that even if he closed his eyes the impression would remain. But he
could not rid himself of the vertigo or the feeling of profound insignificance which the scene
impressed upon his mind.
      Driscoll’s familiarity, however, had made him more immune. He was already at work
under the blister’s dome with refractometer, spectrum analyser, polariscope and sighting
apparatus, relaying vector and tensor co-ordinates to Grus to form the basis for the calculation
of the course. Brevis was fascinated. Driscoll was setting up line, angle and point relationships
by purely visual reference to the Tau-domain image beyond the blister, fixing point
co-ordinates to seven decimal places as though they were physical absolutes. But how the
information was determined, or how it could be established with such accuracy from the Tau
image, he was unable to decide. In this he sensed the reason for Driscoll’s inclusion in the
team. The ability to interpret the Tau image in terms of mathematically usable quanta was
indeed a facility worthy of respect.
     Brevis had no idea at all how it was achieved. If any features were visible at all, they were
vague features of contrasted intensity in the illuminated field, like some cosmological X-ray
diffraction pattern, which Driscoll could read with expert eyes and from which he established
his axes and points, as though drawing an elaborate imaginary three-dimensional spider-web
across the pink backdrop of unreality.
     Finally Sigmund Grus was satisfied.
     “That’s all we need for now, Pat. Computation time is about seven minutes. Paul, I can give
you a deadline in ten minutes.”
     “Right.” Porter’s voice cut in on the communicator. “Primary acceleration will exert an
apparent force of a half gravity in a direction parallel to the long axis of the ship. This is not a
measure of the acceleration rate but a gravitic nuclear reluctance effect which will dissipate
rapidly as the ship leaves the Earth’s magnetic field. Eric, you won’t have experienced this yet,
but just brace yourself against a stern bulkhead until it passes. Sigmund, I’m handing control to
the computer. As soon as the course is taped you can give her the gun.”


                                              THREE

Bred in a world used to the statistics of the crushing acceleration gravities of rocket
spaceflight, Brevis had earlier envisioned their leap towards light-speed velocities would be a
prolonged spell of suffering in an acceleration couch. But in the modified physics of the Tau
domain their actual departure was a physical anticlimax. The half gravity Porter had promised
proved no more than a gentle push against the wall, a force against which he could move and
lean quite easily. The effect was as if the room had rotated slightly on its axis so that the wall
on which he leaned inclined back at an angle and the floor sloped upwards. After a few
minutes both wall and floor returned to the normal.
     When conditions had stabilized and the Tau image remained unchanged, Brevis left the
blister and went to the control room where the activity was now centred. So effortless had
been the moment of departure that he was inwardly slightly sceptical that they had already
achieved a velocity greater than a conventional rocket could ever hope to match. It was also
incredible that they could have developed a rate of acceleration beyond the structural
endurance of any known material operating in a real-space environment.
     Even in the control room the air of unreality grew no less. The T-Döppler radar and
similar devices meant things to Porter and the computer but to Brevis’ untrained eye gave no
more sensible indication of speed now than they had when the ship was at rest. As their speed
climbed to measurable fractions of that of light Brevis was completely at a loss to convince
himself of any condition other than that of being completely at rest. He finally dismissed the
problem and turned his attention to his own charges—the human components of the ship.
     And it was here he discovered, at least in Grus and Porter, that the sense of speed and the
fear of it was very much in evidence. What Driscoll thought he absorbed into himself, but the
tension rising in the other two was a minute by minute tightening of a spring. Real-space
physics postulated the speed of light to be a physical absolute, which nothing could transcend.
But in less than four hours they and their ship were going to challenge that barrier at a velocity
nearing three hundred thousand kilometres a second. Then something was going to have to
give—ship and men, or physical absolute, and nothing in their experience could guide them as
to what might follow. Brevis reflected curiously that while both men had dared to penetrate
so far into the field of Tau physics they still had an inbred fear of transgressing the absolute of
light speed.
     Occasionally he returned to the blister, but the Tau Gamma image held steady and
inscrutable save to Driscoll’s eyes as he occasionally took reference readings from the pink
transience to verify the computed course. The psychologist noted that the image was growing
in intensity, and hardening in such a way that on entering the blister the image would snap into
view rather than simply become apparent as a visual image would. Also its influence
extended farther into the screen maze.
     The strength of the hallucination was now beginning to overpower the visual, so that the
blister layout and Driscoll’s instruments were all assuming an apparent transparency through
which diffused the pinkness of the surrounding image. Even Driscoll and himself were
becoming translucent and losing definition under the influence of the Tau emanation. And,
while the others were inwardly fearing the approach to the light barrier, Driscoll’s fear was
more apparent in the blister, where the shaping and intensification of the image was a tangible
portent of the unknown into which they were headed.
     “I don’t like this at all, Paul,” said Driscoll at last. “Signs are that this image is growing
unstable as our velocity increases. I don’t know what it will break into, but it won’t be a
simple mode jump.”
     “Is that bad?”
     “At this intensity the image is tolerable at the moment because it’s unchanging. But if it
breaks to a living pattern it could become a nightmare in here. And if it breaks fast we might
not even make it to the door.”
     “How so?”
     “It can flay the senses out of you in seconds if you catch a rogue run of images. And since it
can enter and confuse the brain even when you’re unconscious, it can interfere even with the
autonomic nervous system. Then it becomes a killer. I’d say it was a killer Tau storm that’s
brewing now.”
     “Then let’s get out,” Brevis said.
     “You go. I’ve got to take a few more readings while I can still see the instruments.”
      “Then do me a favour,” Brevis said. “Leave the communicator open and report not less
than once a minute. Miss a minute and I’ll be back here to get you out.”
     “Thanks, Eric. I’ll do that. You’ve just five minutes if you want to be in the control room
when we hit the light barrier. I think this image will split wide about then, and it may be
preferable if one of us is elsewhere than in the blister when that happens.”

A simple indication. Two blips on the face of an oscilloscope, crawling inexorably together.
One blip indicating the speed of light, the other giving ship speed. The space intervening
represented the amount by which the ship velocity lagged behind that of light. A narrowing
difference. An approaching unknown.
     Two blips crawling together. Now two centimetres apart, now one, with the basic tenets
of real-space physics stacked high against the odds of their meeting, and the ingenuity of man
pushing fearfully in favour of their passing.
     The sweat stood broad on Porter’s brow. Grus’ fingers deftly laid mathematical
expressions on the keyboard of a computer input. He too was near to breaking under the
strain, but syphoned his nervous energy constantly into symbolic equations representing the
event. The separation between the blips closed to a few millimetres, then to a hairsbreadth
spacing which seemed to endure for an eternity. Then, just as it seemed that the absolute
velocity of light was going to remain inviolate, the blips passed one another. And concurrently
the men experienced an indefinable shiver which ran throughout their bodies as if every cell
had undergone some transition yet still emerged whole and undamaged.
     Porter rapidly checked his instruments and confirmed that they had indeed passed the light
barrier, and that their rate of acceleration was still increasing. The detectors told of a million
kilometre light flare they had wakened in the emptiness of space, but this evidence, was
purely metered information, and inside the ship human senses were still totally unable to
appreciate the fantastic velocity of their passage.
     But Brevis had anticipated the sudden cessation of Driscoll’s voice over the intercom.
Without pausing to share with the others the relief and triumph of the moment he rushed back
through the corridors to the blister. As he passed through the screens he was aware, even
before he could see it, that the image had broken. The kaleidoscope of lights that hit him as he
reached the end of the maze shocked his senses, and he would have lost orientation had not
his shoulder still been in contact with the lead slab of the screen.
     Driscoll was immediately in front of the entrance, invisible now against the strength of
the hallucination, but presumably standing fascinated by the living diorama of the now
overwhelming Tau image. When Brevis grasped his arm he woke as though from sleep, and
allowed himself to be led through the maze like a blind man. Outside, Brevis inspected him
closely.
     “Are you all right? How do you feel?”
     Driscoll bit his lip and smiled wanly. “As well as can be expected. I guess I stayed a little
longer than I should.” His face was deathly white.
     Brevis nodded. “That’s a fair summary. I want you to go to your cabin, Pat, and rest for a
while. I’ll give you a sedative that’ll put you to sleep for a few hours. And I don’t want you to
go back into the blister again until you’ve checked with me. I knew a rogue Tau image was
vicious, but I’d not expected it to have that sort of effect in so short a time.”
     Driscoll’s eyes searched the psychologist’s face, and he seemed about to say something
when a sudden wave of nausea and dizziness caused him to sway and clutch at his head.
Thereafter he leaned heavily on Brevis’ arm all the way to the cabin.

Though the light barrier had been passed, the tensions were still very much in evidence. They
were now facing the great unknowns, a tiny, impudent, splint of metal and humanity fleeting at
super-light speed across the analogue of interstellar space. The probes had previously
achieved this condition also—but the few that had ever returned now formed a mind-twisting
collection of physical paradoxes in the grim museum vaults of Tau Research. But there were
no answers yet as to what had happened to the probes or why.
     Men and computer constantly scanned every available bit and digit of instrumental data,
searching for some clue to the mystery. But both mechanisms and men failed to identify
anything amiss with the project. All known functions were staying well within their
designated parameters, and thirty times a second the computer completed its checks and
returned a negative comment. Grus let the printout tape slip by him unnoticed. Its detail was
irrelevant. Although the computer was satisfied, none of the men could confess to being free
from the nagging apprehension that they had already penetrated past the point of no return. But
whatever the factor which had been added or taken away, it was neither recordable nor
encompassed by their systems of detection.
     Drawn by a certain fascination, Brevis returned once to the blister maze and cautiously
sampled the now rampant image. It blazed in his head and formed such frightening confusion
that he was forced to retire without gleaning anything of value from the experiment. As he
was returning to the control room he found Sigmund Grus bending close to the floor in the
corridor, examining something. He moved to pass, but the physicist motioned him back.
     “Careful, Eric! There is something here I don’t understand. See there—a tiny light shining.”
     Without Sigmund’s direction Brevis would not have noticed the phenomenon for himself,
so minute and intangible did it appear. But following the line of the indicating finger he found
the object, and paused in wonder. In the corridor, unsupported and apparently unaffected by
the airstream from the ventilators, drifted a minute splint of light, like a luminous dust mote. It
took him several seconds to realize that the object was in fact incredibly small and that it was
visible mainly by virtue of its extreme brilliance. It was difficult to imagine how such a
degree of radiation could be sustained by anything so lacking in size.
     “What is it?” Brevis asked at last.
     “It could be a projection of something from real-space into Tau—a sort of breakthrough
of atomic condition.”
     “I thought that was impossible.”
      “It’s barely possible, even in theory. Projection requires an extreme degree of excitation
on the part of the basic atom—a very extreme degree, I can assure you.”
     “How extreme?’
     “The excitation state involved in nuclear fusion, at least.” Grus appeared thoughtful. “But
something tells me this isn’t a simple projection. This is something new. Such a thing should
never exist, even as a projection. You couldn’t have a self-sustaining fusion reaction that
small.”
     He produced a pencil and probed the splint carefully. It did not move, but seemed rather
to penetrate the pencil and emerge unchanged. He examined the pencil in silence.
     “I don’t like this at all,” he said finally, holding the pencil up to the light. “Would you fetch
Paul?”
      Porter came without comment. The top-line frown reflected the fear which was already
clawing deep in his guts, and the new phenomenon could add no more or less to the burden of
responsibility he was already carrying. Brevis watched him carefully for signs of hysteria, and
was relieved to find none.
     When they reached the corridor Sigmund had extinguished the overhead fluorescent
panels, and was observing his discovery against the background under the dim illumination of
the tritium safety lamps. In this setting the splint burned inconceivably bright for its size,
casting a clear glow on the bulkhead.
     “Don’t touch it,” Grus warned. “It could be dangerous. I want to try a test.”
     He went off to the laboratory and returned with a square of fine tungsten foil. He passed
this several times through the point of light. It remained unmoving. Then he ran to the optical
room and closed the door. A minute later he was back.
     “Holes right through,” he said. “I don’t think this can be a projection. Its heat is incredible
but the holes it makes are so minute that they’re hardly capable of being resolved with our
microscope. Nothing that small should possess that sort of energy. Paul, I want to do a
spectrum analysis on this thing.”
     “I’ll help you,” Porter said. “But we’ll have to dismount the spectrograph and fetch it out
here since we can’t pick that thing up.”
     “Can I assist?” Brevis asked.
     “Not much at the moment, Eric. We’ve some delicate work ahead of us, and its
specialized. We’ll let you know our findings when we’re through.”
     Brevis nodded and returned to his cabin. He had the curious impression that both men
already suspected and feared what their findings would be. He checked through his stocks of
tranquillizers in the store-cupboard and wondered just how long such mental and intellectual
strain could be offset by purely chemical means. At some point a psyche was going to refuse
to be pacified by drugs, and when that point came somebody was going to snap. Driscoll was
already showing signs of breaking up. And who next?
     It was about an hour later that Porter knocked on his door.
     “May we come in?”
     “Do.” Brevis pulled down the other bunk to form a seat and beckoned him in. Grus
followed, still studying the long strips of photographic paper from his instrument. His hands
were trembling.
     “We’ve found what it was, Eric.” Even at that point Porter was reluctant to put a name to
his fear.
     “I think I already know,” said Brevis quietly. “It’s a star.”
     “You knew?”
     “I guessed about the same time that you did. But I was expecting it. You weren’t.”
     “But a star . . .” said Porter, and his voice was ragged. “It’s a spectral G-type sun, similar to
Sol. It could measure perhaps a million miles across. And it’s out there in the corridor like a
point of light so small you can hardly measure the holes it makes. Christ, Eric, if that’s a sun
out there—what size does that make us?”


                                                FOUR

Putting his empty glass unsteadily back on the table, Porter pushed the hair from his face.
      “I still don’t see how you could have anticipated this, Eric.”
      “Not exactly this, but I was prepared for something of this nature. I saw the Tau probe
vessel which came back only twenty-two inches long. This is part of the same pattern.
Somehow, Paul, entry into deep-Tau cuts things adrift not only from the universe but from the
controlling physical constants of the universe. I’ve no idea how long the ship is now, but if you
want to try the calculation, start by using light-years instead of metres.”
      “And yet you aren’t frightened silly at the prospect?”
      Brevis refilled the glasses from the bottle on the table.
      “No. So far the survival threats here are purely intellectual ones. It would take a
well-trained mind to appreciate that we three, sitting here drinking whisky, regard ourselves
as being close to death. And if asked what form of death, we none of us could even define it.”
      Porter watched his face carefully for a moment. “You’re dead right of course. We’ve come
unstuck from the universe, certainly, but so far it’s panic not physics which is most likely to
kill us. Sigmund, have you enough data to calculate our size from the dimensions of that star,
assuming it’s a regular G-type dwarf?”
      “I’ll work on it,” said Grus. “But there’s a more urgent problem first. That star must have
entered through the hull, and therefore left a puncture. I think our first concern must be the
preservation of our atmosphere.”
      “If the holes it made in the hull are no greater than those it made in the foil, the air losses
won’t be measurable.”
      “True. But that’s only a simple G-dwarf. What happens if we run up against a giant like
Betelgeuse? That would make a hole we couldn’t afford to ignore. I suggest we try to navigate
in a direction away from the island universes until we’ve some idea of what we’re up against.”
      “Good point,” said Porter. “I’m going up to the control room to see if we can get sufficient
information from the instruments to give us a bearing on a relatively unpopulated region of
space. I could use Pat’s help, Eric. Is he still sleeping?”
      Brevis glanced at his watch. “I gave him a sedative about four hous ago. He should be out
of it by now. I’ll go and wake him.”
      “Get him to join me in Control. We’ve got instrumentation for detecting stellar objects in
real space, but whether it can detect star systems the size of meteorites projecting into Tau is
a rather different problem. Is it possible to use the blister?”
      Brevis shook his head. “That’s completely out of the question. The Tau-psychic interaction
in there is so strong it would drive a man senseless in fifteen minutes, and kill him in thirty.”
      Porter nodded his acceptance of the fact and went out of the door. Brevis’ own intention
of following was delayed by a sudden gesture from Grus towards the end of the room. Through
the wall of the cabin another star had drifted, and they both paused in fascination as the tiny
splint of light cleared the mirror of the table top by a centimetre and neared the whisky bottle
standing in its path. Brevis moved to take the bottle out of the way, but Grus stopped him.
      “Wait, Eric. There’s something we need to know.”
      The splint touched the bottle and penetrated slightly into the glass. Then with a crash the
bottle shattered, scattering liquor and glass on to the table and the floor. The star, apparently
unaffected, continued its slow, amazing journey across the room.
      “Bad!” said Grus. “We none of us dare sleep with those things drifting through. At best they
could be painful, at worst, lethal. Can you imagine waking with one of those entering your
temple? Even walking into one could cause a pretty nasty injury.” He glanced around him. “And
it’s only a matter of time before one of them cuts some wiring or hits something vital. And . . .
Oh my God!”
      Brevis was caught by his sudden spasm of alarm.
      “My God!” said Grus again. “I’ve been worrying about the heat and visible spectra, but
those things must be chucking out hard radiation as well. Not only could they be a fair
biological hazard, but if one of them gets into the computer it’ll flip every solid-state device
in the whole assembly. The whole control system will go haywire, to say nothing of the loss of
the computer function. You’d best get Pat up to Control fast. I’ll try and get a radiation check
on this one, but unless I miss my guess we’ve a death threat far more tangible than panic
already with us.”
      Brevis tried to raise Driscoll on the intercom, but failed. Carefully avoiding the star in the
corridor he ran to Driscoll’s cabin. It was empty. The sheets on the bed were still warm, but
not too recently occupied. Swiftly he checked the few other likely places. They were
similarly bare. Then he flipped the emergency communication button.
      “Paul! Sigmund! Is Pat with you somewhere?”
      “Not here,” said Grus.
      “Nor in Control.” Porter’s voice carried a note of alarm. “What’s the matter, Eric?”
      “I’ve an idea the damn idiot’s gone back into the blister. The image there is so ultra-real it’s
almost addictive. I’ve noticed a similar tendency in myself. Once you’ve experienced it you
can’t let it alone.”
      “Damn!” said Porter. “Have you tried him on the intercom?”
      “He must be hearing my voice now,” said Brevis, “but if he’s in the blister he won’t respond
because the Tau image will represent the dominant reality. Pat, for God’s sake, if you can hear
me, answer!”
      The set returned only silence and little electronic sounds gathered from various parts of
the ship.
      “Then he’ll have to stay there until the course is re-set,” said Porter.
      “No. He could have been there ten or fifteen minutes already. Leave him exposed for as
long again and we won’t need to fetch him out. Just paint R.I.P. on the blister door and pack his
effects for his relatives. That’s a killer image in there. I’m going to try and help him.”
      Without waiting for Porter to reply, Brevis ran directly to the blister door. It was slightly
open, though he knew it to have been closed the last time he had left. The telltales on the wall
indicated that the screen maze inside had been altered or damaged. This in itself was sufficient
to show that Driscoll had entered and therefore needed help.
      Before he could enter, Grus arrived. Porter was close behind. Porter summed up the
situation with a quick glance, and turned to Brevis.
      “I can’t let you go in there, Eric. Pat’ll have to take what’s coming to him. I daren’t risk
losing you too.”
      “And we daren’t risk losing Pat—not if we ever want to find our way home again. He may
be unconscious, but I doubt if he’s dead yet. There’s still a chance of getting him out alive.
Later there won’t be.”
     Porter came to a sudden decision. “Very well. But you go in with a rope around your
waist. You’ll have five minutes, and then we’ll haul you out if necessary. And try not to fall
down among the screens or you might get hurt on the way out.”
      “If you insist.” Brevis stood submissively while Grus fetched a rope from the store-room
and fastened it round his waist. Porter caught him by the shoulder.
     “Five minutes, Eric—and good luck!”
     Brevis shouldered open the heavy door and entered. It was quite dark inside, and, as the
telltales had indicated, the internal screens were disarranged. All he could see initially was a
fuzz of diffused polychromatic light which crept around the disordered lines of the lead
panels. Seeking orientation, he moved back to the wall and sought the light switch.
     As his fingers moved the toggle he was engulfed by a wave of vibrant, dancing, idiotic,
multi-coloured patterns, which swarmed in front of him like a living kaleidoscope. The
imagery trapped his senses in a mesmeric focus which almost robbed him of his power to
react. Mercifully the toggle remained under his fingers and he snapped it off urgently,
thankfully relaxing in the return of darkness.
     “Are you all right, Eric?” Porter’s voice sounded a hundred times farther than it should.
     “Just about,” said Brevis. “Deep-Tau emanation and A.C. lighting make a formidable
combination. I couldn’t stand that for long. I’ll do the rest blind.”
     Slowly he found the screens and devised a path between them and across those which had
fallen, scowling at the thought of the psychic paroxysm which had driven Driscoll to attack
the heavy screening with such irrational violence. The edges of the lead sheets appeared
fuzzed and burred with a polychrome haze which grew stronger as he entered through the
maze and hinted at the violence and turbulence of the Tau-psychic effects rampant in the
blister proper.
     He searched each area urgently with his hands, hoping that Driscoll had fallen between
the screens and away from the awful aura ahead. But he knew in his heart that this would not
be so, and he felt a wave of fear at the prospect of having to penetrate finally into the
unshielded extravagances of the raw Tau influence.
     When he turned the last corner into the blister the wave of imagery and sensation tore
down at him apparently from all sides, swamping his senses and leaving only the single core of
his objective mind to guide him in his purpose.
     Dazed by light and form and colour, his eyes attempted to follow and analyse the
geometrically untenable planes and images as he trod apparently through a macrocosm of
chaos which only his iron resolution reminded him was the blister floor. His mind seized on
the shattering images and attempted to rationalize them into meaningful terms and
comprehend the semantic substance with which every line of light was seeded. Every now
and again his imagination became caught in a snare of some intriguing speculation, and he had
to wrench his mind free with almost physical effort, knowing the deadly penalty for
indulgence.
     He could understand now the fatal attraction of the Tau images for Driscoll. The brain
received the images direct, without the filtration and attenuation of the normal human senses.
The mind was released from the mundane bonds of limited sensory experience, and could
swing, undamped, in domains of previously unfathomable concepts, without the distractions
and reflexes of the body.
     A savage jerk under the ribs brought his own wandering thoughts back to focus on his
mission. He stumbled over Driscoll’s body on the floor, but fortunately did not fall. He could
see nothing of the form he caught up to his shoulders, only the variegated colours of the quasi
infinities which clawed at his mind with snags of intangible steel.
     Again the rope caught at his chest, this time insistently. He hesitated, having no means of
gaining his bearings in the unchartable fantasies in which he was immersed. The rope had now
become the sole link with another sort of reality, an invisible umbilical cord connecting him
across the unknown to an isolated, dark womb of fear and apprehension which was the ship
and its situation. He felt an irrational desire to slip the knot and not to return to the
worry-shrouded oppression of shades with its precarious chance of re-birth.
      The third pull of the rope was decisive. Before he could re-arrange his burden so as to get
his fingers to the knot he was dragged forcibly against the screens and through them, until, near
the end of the ruined maze, darkness closed down again and the mental turbulence grew quiet.
Hands seized him in the darkness and slipped the body from his back, then thrust him outward
into a different kind of light—the cold, fluorescent harshness of reality. He fell into the
corridor and remained there for many seconds, shaking the images from out of his head, until
Porter came and helped him to his feet.
      “How do you feel, Eric?”
      “Grim. But I think it will pass.” He looked up and saw the door of the blister still part
open. “But it’s not a risk I’d care to take again. Can you fix that hatch permanently closed?”
      “I’ll weld it shut,” promised Porter. He looked at Driscoll, now laid desperately
unconscious in the gangway. “Not that it looks as if he’ll be interested in it for a while.”
      “I wasn’t thinking of him,” said Brevis. “I was thinking of myself.”

Outwardly, Porter’s evasive manoeuvre seemed to be a success. His instrumental questing
finally located a direction in space where the stellar population was obviously less. Breaking
the pre-set course co-ordinates, he manually directed the ship in this direction. Miraculously
both astral bodies which had entered the hull drifted slowly out through the fabric again
without detectable damage to the vessel. Then they waited. No further cosmic intruders
penetrated into the ship, and finally they relaxed.
     This gave them the respite needed to consider their plight more logically. But internal
tensions were creeping dangerously high. Brevis was more than anxious about the continuing
stress and its inhibiting effect on the type of intellectual free-wheeling which the problem
demanded.
     Grus was tending to concentrate his energies on routine tasks, as though trying to
convince himself that he did not have time enough to grapple with the major problem.
Driscoll was being maintained in a state of light sedation after his experiences in the blister,
and was therefore intellectually inactive. Even Porter was having difficulty in bringing his
mind to a position of logical attack.
     “The hell of it is,” said Porter, “you can’t even find a point from which to start solving a
problem like this.”
     “You’re not thinking too clearly, Paul,” said Brevis. “You’re allowing yourself to be fazed
by the size of the concepts instead of looking for fundamentals. I’m no physicist, but the
problem appears to me to be one of congruency. We’ve lost physical congruence with our
own universe. We’re no longer controlled by whatever factors control the size of things.
Now, what factors do control the size of things, Paul? Why is anything the size it is, rather than
a million times larger or smaller?”
     “A good question,” said Porter, “and way outside my field. I don’t pretend to know the
answer. The size of a thing is always relative. I suppose the nearest thing to absolute units are
the sizes of the atoms and molecules from which matter is constructed. Aggregates of matter
generate and are acted upon by certain forces—molecular binding forces, gravitation,
centrifugal forces and the like, which roughly determine the mass-range which that type of
object normally achieves.
     “It’s the interaction of possible states of matter, and the forces generated by them and
acting upon them, which appears to control the size of everything in the universe. You can’t
have a molecule as large as a star or a star as small as a molecule because either would be
unstable.”
      “Then what happened to place us outside this control?”
      “I don’t know. We were in a state of Tau-spin resonance when we accelerated through the
speed of light. It’s beginning to look as though the Einsteinian mass-velocity relationship does
apply in Tau, but in a peculiar way. Instead of the velocity being limited to that of light, we
passed easily through the light barrier, but tore our own atoms free from the controlling
influence of the universe instead. Effectively we’re a universe in our own right now—still
self-integrated, but unconnected with any other universe. And Heaven alone knows what
factor is controlling our absolute size relative to the universe from which we started.”
      “Are we still in Tau-space?”
      “The Rorsch generator is still running, but our molecular density is so low relative to the
star stuff through which we’re passing that it’s doubtful if a true Tau state is being maintained.”
      “Can’t we just reverse the process and drop back through the light barrier?”
      “We’re trying,” said Porter, “but there’s no indication yet that it’s going to work. Since we
cleared the star patch we’ve been winding down our speed—eighteen hours, and we still
aren’t much above light velocity now. So far our size has done nothing but increase slightly
more. I’d guess that once our atoms were torn from the universe they found some arbitrary
relationship of their own which is independent of velocity.”
      “That’s a key factor,” said Brevis. “This arbitrary relationship—I’m not convinced it’s true. I
suspect there’s still some relationship between our present size and the size we were when
we started. I think there must be some connecting link. Can we check this at all?”
      “We can fling all our co-ordinates into the computer and see if we can spot a relationship.
If there is a controlling principle it should show up as a function of something.”
      “Will you do that?” said Brevis. “If you can isolate the controlling factor it gives us a
possible method of attack on the problem by attempting to reverse the issue.”
      “I’ll get Sigmund on it right away. If we spot anything I’ll let you know immediately.”


                                                FIVE

In this, Brevis had at least achieved his object of getting Porter to apply himself to the task.
Once a line of investigation had been initiated Porter could be relied upon to follow it to its
logical conclusion. Even if the research proved futile, he had at least set up the pattern of
attack. He was not therefore surprised when Porter’s next communication carried a note of
enthusiasm.
      “Eric!” Porter was speaking from the computer room. “I think we’ve isolated the
controlling factor. The computer has thrown up an interesting set of constants which give an
extrapolation back to the time of our breaking the light barrier. The constants are independent
of velocity or distance from point of origin, but they are related to elapsed time.”
      “How does this affect us?” Brevis asked.
      “Frankly it means the longer we stay in this state the larger we shall become. We’re like
the proverbial exploding universe. Where stars can now float through the ship, soon it will be
galaxies. Can you imagine . . .”
      “Shut up!” said Brevis sharply. “I’m trying to think. I don’t believe this is any accident, Paul.
It’s rather what I suspected. Now think carefully. Is anything at all still tying us to the old
universe? For instance, on what do we base our conception of measured time?”
      “All our instrumentation is related back to the master oscillator. That itself is
synchronized with . . . Eric, you may just be on to something. Look, I’ve got some checking to
do. I’ll call you back in a few minutes.”
      Brevis acknowledged the hastily broken connection with a raised eyebrow. His eyes
automatically wandered to his precious drug cabinet. As an explorer of the human mind he
had learnt the humility of the chemical modification of human outlook. Any mind-state could
be conditioned for better or for worse by a few micrograms of the right substance in the
bloodstream. He had drugs which could make his comrades accept their present situation
with joy or equanimity, but nothing in any phial or bottle which could fire the spark of genius
they needed to resolve the problem.
      His reverie was interrupted by Porter’s insistent buzz on the intercom.
      “Eric, I’ve got a lead. Don’t ask me how, but we’re still receiving timing pulses from the
Tau Research transmitters. A ten kilocycles square wave. Is this the sort of thing you were
looking for?”
      “It could well be. What do we do with it?”
      “Use it to correct our own master oscillator. In effect we’re using it as a time reference
for damn nigh every time constant on the ship—clocks, transmitter, instruments,
computer—the lot. The master oscillator crystal is pulling like hell, but it’s still synchronized
with the reference signal.”
      “So all our time referents are still tied to the old universe?”
     “Effectively, yes. What do you suggest we do?”
      “Turn the receivers off. Kill the signal.”
      “First let’s consider what that’s going to achieve. If the time constant has any bearing on
the size of this ship, what happens if we cut adrift from it? We will lose our very last point of
congruence with the universe. We’re already adrift in the three physical dimensions. If we
lose congruence with time also, our chances of ever getting back would appear to be
remarkably slight.”
      “Something’s controlling our size,” said Brevis. “And the computer’s proved it’s no casual
relationship. But that controlling factor has caused us to become about four light years longer
than we started out. I would guess that somehow our size is attempting to compensate for an
untenable time constant to which we are tied regardless of velocity. As I see it, our only hope
is to break every possible link so that our size determinator is a purely arbitrary factor. Then
we have a chance to do some research into instituting our own control.”
      “I think it’s a hell of a risk, Eric. Better the devil we know than the one we don’t.”
      “How much do we know about this devil called time Paul?”
      Porter considered this in silence. “Very well! I’m turning the receivers off now. But I wish
to hell I knew what you had in mind. I know there’s something buzzing in that brain of yours.”
      “Perhaps. I’m wondering whether to take a gamble, based on something I saw in the vaults
of Tau Research. When you can show that our size determinator is arbitrary I’d like to set up
an experiment which I think might work. I think it stands a chance because I suspect that it
was tried by somebody once before. Somebody who finished up one and a quarter inches tall.”
      There was silence for a long second. “At this stage, Eric, any idea is better than none. How
do we set about it?”
      “I need to tidy up a few details first. So I’ll give you the proposition in its final form. And
Paul . . . !”
     “Yes?”
      “I’d appreciate it if you’d keep this to yourself for a while. You understand why.”
      “Sure, Eric. The whole situation’s a psychological bomb.”
      “Check! Get those receivers off and have Sigmund watch the computer to see if the
linking factor is broken. When you’re sure the time correlation has gone let me know—but
quietly. Hullo, Paul, are you still there?”
      “Sorry. I was just thinking. I wonder what it’s like to be one and a quarter inches tall?”
As he cut the connection Brevis noted that his own hands were shaking. The scheme which
had formed in his mind in the course of the conversation was one born of desperation, and
would involve the type of risk that only desperation could justify. That the idea had sprung
from his own mind was a fascinating insight into the pressure of the fear which lay in his own
subconscious. And, despite his words, it was not something he could discuss with either
Porter or Grus. In fact, there was only one other person aboard likely to be able to follow his
reasoning and appreciate the nature of the experiment.
     Slowly his considerations formed into a practical plan of action. Some of the steps he
was loath to take, but again the sense of desperation forced the conclusion that there was no
other course. He knew now what drugs he could use and to what purpose.
     Then he reached the point of decision, and moved swiftly. From the automatic kitchen he
removed the coffee dispenser and doctored the first two charges of coffee concentrate. From
the surgery he took a couple of pre-sterilized hypodermic syringes and two ampoules, which
he concealed carefully in his pocket. And all the while he was watching the clock, knowing
the shipboard habit pattern with such certainty that he could afford to let affairs take their
own course up to a point where his active intervention was necessary.
     The only new factor to be added was Porter on the intercom, his voice ragged and near
hysteria.
     “Eric, the time link factor’s been broken. But we should never have switched off the
receivers.”
     “Why, what the devil’s happened?”
     “It’s the stars, Eric. My God, what have we done?”
     “What’s the matter with the stars?”
     “I thought the instruments were broken, but it isn’t that. I’ve checked. But the stars have all
gone out.”

Brevis verbally strove to quell the rising panic, playing for time. To ensure that the coffee
reached its intended destination he collected it himself and took it to Grus and Porter, and
stood for a moment while they tried to coax the computer to handle mathematical concepts
of infinity for which no programmes would ever be available. The unmistakable smell of fear
was heavy in the air. Brevis estimated that the knockout drug in the coffee would be effective
in about five minutes, and was somewhat apprehensive when Porter decided to consult the
micro-reader in his own cabin just before this time. He followed Porter discreetly, to be on
hand in case he should fall on the stairs. But Porter continued safely almost to the cabin before
he fell unconscious in the corridor.
     Brevis caught the fallen figure under the armpits and dragged it in to the bunk. Baring an
arm, he prepared a hypodermic syringe and made an injection. Then he stopped and looked
about him. The ship seemed curiously still. Only the whispered rustle of the automatics and
the slight sound of the air conditioning system broke the silence. There was no drive
operating, not even for routine attitude or spin correction. Even the power hum had fallen to
an inaudible level, and the Rorsch generator, working in such tenuity, had long since ceased to
voice its characteristic harmonics. In these conditions he imagined he could hear the
molecules in the walls around him creaking as they strained to find some controlling
principle which would set their absolute as well as their relative size.
     He went out into the corridor and then back up to the computer room looking for
Sigmund Grus. The physicist was already asleep, his head resting on the console. Brevis moved
him to the floor and gave him an injection as he had done with Porter. Then, satisfied, he left
Grus at rest, and headed for Driscoll’s cabin.
     Driscoll woke up at his entry and propped himself sleepily up in the bunk, an unspoken
question on his lips. Brevis seized his wrist and checked his pulse impatiently. Then nodded.
     “Get up! We’ve got work to do.”
      Driscoll scowled at the abruptness of the address, but complied nevertheless, swinging
into his working jeans, all the time his deep eyes trying to wrest information from Brevis’
impatient face.
      “Now what? What’s going on?” Even waking from sleep Driscoll took it as axiomatic that
something unusual was in progress.
      “We’re going into the blister. Paul’s welded the door shut, so get a cutting torch and join
me there.”
     “But Paul’ll never . . .”
     “Paul can’t stop us. Nor Sigmund. I’ve got them both under sedation. Now I’ve got some
work to do in the blister and I need your help. What’s the matter—don’t you dare?”
      “You know how much I’d dare to get back in there.” Driscoll’s intelligence shone through
the perspiration on his brow. “But God, Brevis, I hope you know what you’re doing! Was it you
who got me out?”
     “Yes. That’s how I know how much of it I can stand and how much you can stand. It should
have killed you, but it didn’t.”
      “After a while you learn to come to terms with it. The effect of Tau imagery is essentially
akin to a drug experience. When it’s as strong as we found it in the blister it can combine
mescalin fantasy with opiate addiction. And there’s a limit to what you can take and still retain
your own volition. But you can prolong your tolerance by repeated exposure.”
      “This time,” said Brevis, “there’ll be no question of even trying to retain your own volition.
We may have to go well beyond that point. The best we can hope for is that one of us can
retain sufficient objectivity to complete the job.”
     “What job?”
      “Getting the ship back into congruence with the universe from which it started.”
      Driscoll watched him narrowly for a moment or two. “I know you’re not mad, Brevis,” he
said, “so you must have some idea behind what you’re saying.”
     “It’s more of a hunch than an idea. In the vaults of Tau Research I saw a probe vessel
twenty-two inches long with a pilot to match. What intrigued me was not so much that he
finished up at such a size, but why he happened to finish up at that particular size. I wonder
now if I’m beginning to see an answer.”
     “Go on.”
      “My theory is this. His probe vessel, like ourselves, probably broke dimensional congruity
with the universe due to some Tau phenomenon when passing through the light barrier. And
like ourselves, by accident or design, he established that his size determinator was an arbitrary
factor.”
     “Is ours?”
      “It is now. We were apparently maintaining time congruency with the universe due to our
dependence on Tau Research timing pulses. This link we’ve now broken. So we should have
access to the same sort of control which I think the probe pilot used to correct the size of his
ship.”
     “Which is what?”
      “Imagination. Tau-psychic interaction is something we can prove to exist even though we
don’t yet understand it. The Tau hallucinations in the blister are part of it. An area of the brain,
apparently located near the so-called pineal eye, responds directly to unshielded Tau
influence, and there is evidence that certain aspects of Tau are mutually responsive to strong
psychic states. I suggest that having realized the size determinator of his probe was arbitrary,
the pilot went into the blister and attempted to mentally correct the size of his ship by
reference to the Tau image. He literally thought his way back into near congruence.
Unfortunately he overshot the mark, but when you consider through how many orders of
magnitude he probably descended, it was a feat of genius.”
       “My God, Brevis!” Driscoll was standing now, his eyes alight with comprehension. “I was
in Control when that probe came in. You couldn’t have known this, but the pilot was in the
blister when it arrived. I got him out with a spatula and my thumb. I’ve had nightmares about it
ever since.”
      “I guessed as much. But are you willing to attempt the same thing?”
      “Of course. We don’t have anything to lose, after all. And if it worked for him it should
work for me. But I’m not too certain about you. After certain minimal exposure to Tau
hallucination one tends to become . . . ‘wedded’, as we pilots say. But the honeymoon period is
a pretty harrowing affair. I suggest you stay outside the blister and leave the manipulation to
me.”
      “I would, but for one thing,” Brevis said. “When you’re pitting your own psyche against the
truly infinite it takes a rare degree of dissociation to establish your own status accurately. The
probe pilot underestimated himself with disastrous results. You’re an outstanding introvert.
Any error in your judgment will necessitate the use of a microscope to extricate us from this
ship. Conversely, I have insufficient experience of Tau imagery to drop us through even one
order of magnitude. But I do have enough training in psychological balance to correct us to
approximately the right endpoint. As a composite we have a chance of bringing the size of the
ship to a point where Paul and Sigmund may usefully survive.”
       Driscoll accepted the point without comment. “When do we start?”
      “The sooner the better. The others will be out for about three hours, and the less
imaginations we have working at once the more likely we are to succeed.”
      “Is that why you put them out?”
       “I despaired of ever trying to convince them of the scheme which you have accepted
almost without hesitation. That’s why I approached you alone. I also put them out as a humane
precaution which I cannot extend to either of us.”
      “Which is?”
       “At our present size we could include a whole galaxy in the ship and never notice it. But
when we start to descend through a few orders of magnitude you can imagine our
predicament if we happen to include within the ship’s structure even one solitary expanding
star.”


                                               SIX

Seeing his unfamiliarity with the tool, Driscoll took the cutting torch away from him and cut
deeply into the metal, causing a shower of burning metal droplets to cascade to the floor.
Then he levered the still white-hot metal open with a bar, and forced the door back with his
foot. But despite his exertions, the sweat that beaded his brow was of emotional rather than
physical origin. He stood aside for Brevis to enter.
     After their last desperate emergence very few of the screens remained standing, and the
extremities of the unshielded Tau emanation seemed to burn off every angle and projection
with an intensity which was almost audible. Brevis did not need to enter far to know that the
savagery of the raw Tau influence was considerably greater than it had been even when he had
almost succumbed while getting Driscoll out. Both his hope and his determination drained as
the force of the situation hit him. Driscoll, coming up behind him, stopped abruptly, appalled
at the intensity of the effect.
     “Jesus! That will eat us alive. We could never function in there.”
     “You don’t think we could stand it?”
     “We might stay conscious, but it wouldn’t be possible to think. It would be almost a
complete mental wipeout with that degree of activity.”
     “Let’s get outside again,” Brevis said, “and see if we can find another angle on this.”
     Back in the corridor they closed the damaged door and leaned against it, thankful for the
respite.
     “We’ve not much time, Eric. The level’s rising all the while. Whatever we decide will
have to be done soon. If it gets much stronger it’ll strip us senseless before we can get through
the screens.”
     “Can you think of anything at all which might give us a lead?”
     “Given some sort of focal point or target on which to concentrate, it might just be
possible to remain objective. But you’d never handle abstractions against that level of
interference.”
     “Tell me something,” said Brevis. “When I went into the blister to get you out, I put on the
light at the door side of the screens. There was some Tau emanation leaking past the screens,
and the interaction nearly blacked me out. Is this usual?”
     “No.” Driscoll’s eyes were shrewd with their dark intelligence. “It isn’t usual, but it
happens sometimes. Occasionally in terrestrial Tau work the ship breaks from real time into
the Tau temporal analogue. Under Tau emanation in a blister the light attempts to make the
real-to-analogue transition and you get the same impression twice—once visually and once
via the Tau hallucination. But the two signals are out of phase and set up a ringing pattern in
the brain.”
     “I see,” said Brevis. “That accounts for the patterning of the image.”
     “Probably. But it has its uses. The ringing sets up something similar to a mental moire
fringe interference pattern from which an experienced man can read the time differential
with almost micrometer accuracy. Using a narrow-band light source with controllable
illumination, it makes a useful research tool.”
     “Have we got such a source?”
     “We’ve got a mono-isotope krypton 86 discharge lamp in the blister. That’s about the best
available. With it you could detect an analogue-to-real time displacement of less than two
milliseconds. Does that help?”
     “It just might,” Brevis said, “if you could use the lamp as your focal point and concentrate
on correcting only the time differential.”
     “How would that help?”
     “Since we broke the link with the Tau Research timing pulses, the ship analogue time has
adapted itself to fit the same controlling constant as ship size.”
     “Are you sure of that?”
     “Porter told me the stars had all gone out. This suggests there has been a time shift from
real to analogue time. Our time scale is now so vast that normal light frequencies just don’t
register with us. It’s too much of a coincidence that the stars disappeared just after the
receivers were turned off. I surmise that if we can get one dimension back into congruity, the
others will follow. After all, they’re all now tied to the same controlling constant. Alter one
dimension and the others must modify themselves to balance the equation.”
     Driscoll pulled his lip. “The whole theory’s based on far too many assumptions.”
     “We don’t have time to re-examine the data. Unless you’ve anything better to offer I
suggest we go back in there and try it.”
     “You’re right, of course. At this stage even a bad theory is better than none. And if we’re
going to die anyway, I know where I’d prefer to be.”

Driscoll opened the door and walked towards the blister. Brevis followed, hiding his face in
the shadow of Driscoll’s fading silhouette—a shadow made surrealistic by the polychromatic
fuzz which made nonsense of the outline. The crackling lure of the bright imagery seized his
mind and drained his volition. He followed like an automaton, with his eyes fixed on a
narrowing area of darkness which was the small of Driscoll’s back. And in his mind there
nestled an even smaller and more rapidly reducing area of objectivity.
      Driscoll was in the blister now. Forcing his hands to find and operate familiar instruments
now entirely invisible because of the strength of the hallucination.
      “Lamp on,” Driscoll said. “It’ll take a few minutes to warm. I’m sitting right in front of it.
Make it easy on yourself. Go outside and wait.”
      “I’m staying,” Brevis said. Unable to orientate himself with respect to the now unseeable
blister layout, he sat down on the floor. At rest, the impressions overwhelmed him. The Tau
images, suffering no attenuation through the limiting filters of the body, assumed an exquisite
fidelity and “edge” which he found both intolerable and irresistible at the same instant.
      There was no way now to shut out the startling excitations, nor any way to keep his
personality contained. The Tau-psychic interaction continued through to fusion point, and its
effect was one of mental dispersion, as though his consciousness was being distributed
homogeneously into the surrounding phenomena. His mind and the Tau-space imagery
momentarily seemed fused into one.
      It was later that something left of himself tired of being alone and infinite, and tripped his
attention to Driscoll’s disembodied voice rambling in the midst of chaos. Only one phrase was
sufficiently articulate to be understood—but that was sufficient to shock his mind back into
narrower awareness.
      “Brevis . . . stop fighting me. Is that what you want . . . infinity?”
      In that instant of revelation Brevis forced his mind to withdraw from the fantastic rapport,
and forced his muscles to carry him to his knees. As he did so a new form of image forced
itself into his head—great sliding bands of alternate light and darkness, slipping, twisting,
moving always downwards. Then he knew that his eyes had come within the range of the
krypton lamp. This was the moire fringe effect, though what was visual and what was
hallucinatory he was unable to decide.
      But he was conscious that Driscoll was somehow forcing the bands downwards across the
field of view, seeking a smaller pattern, a smaller differential between their time and the real
time of the universe. The flickering bands cascaded to a blur of grey, then slowed as Driscoll
paused for a closer examination of phase, angle and magnitude.
      Brevis relaxed, and in doing so he lost the image of the moire fringe. The turbulent Tau
image crowded over him again, slipping away on all sides in a torrential series of changing
modes and characters breathlessly unlike anything he had previously experienced in Tau.
Unable to regain his vision of the fringe, he attempted to remain a passive observer as the
drunken kaleidoscope of subjective impression veered down an ever-narrowing funnel of
restricted effect.
      The thought formed hazily in his head at first, and then with a clear and rising panic, that
Driscoll had lost control. The descent seemed too far and too fast, and they were gaining an
impetus which it appeared impossible to halt. From the infinitely large, Driscoll’s own
introspection was threatening to drive them into the infinitely small, and they stood the risk of
becoming voyagers in some untenable sub-nuclear domain.
      Brevis attempted to extend his mind into correlation with the now fleeting image. But the
relative velocity between the phenomenon and the speed of his own thought processes defied
the contact and threw him back with a headful of sparks. And his panic grew to a certainty as
the velocity of the descent increased still further as judged by the transience of the parade of
imagery.
      Once again he attempted to enter the battle, and this time his mind caught and held, but
with a mental wrench that almost stripped him of consciousness. Then he was back again,
fighting to re-form the patterns of Tau image with which he had become acquainted through
exposure to more normal states of Tau.
      Then suddenly stasis, quietude, rest; a synchronous locking. He caught at the image and
held it, and the whole scene stabilized in the rose-pink panorama of the Tau Gamma mode
illusion. It seemed they had arrived.

It took him many minutes to collect his senses and to take stock of the situation. The intensity
of the Gamma image was low, and the krypton lamp, now itself visible, provided sufficient
illumination to draw out other real details against the pink hallucination. Stumbling to his feet
Brevis located the switch for the blister’s internal lighting. Immediately the normal details of
the room became apparent and the pinkness shrank back to a mere ghost of an illusion.
     Driscoll had slipped from the chair in front of the lamp and was now prostrate on the
floor. Relying now on his eyes, Brevis sought a path through the disordered screens and
dragged Driscoll out to the corridor. A swift examination suggested he was not dead but
merely in a state of shock. Despite the urgency which the treatment of Driscoll seemed to
merit, Brevis felt impelled to visit both Porter and Grus on his way to collect his emergency
case. Both were still sleeping, but stirring and shortly due to wake.
     It was only when he reached his cabin that his experience in the blister caught up with
him. As he opened the door a brief confrontation of his own face in the mirror filled him with
confused amazement. In attempting to correlate the death-white idiotic features which he saw
with those of his normal image, the wonder and the horror caught up with him. He had a
vague impression of falling as delayed shock drove the resistance from his body and tipped
him into a pit of unconsciousness.
     When he finally awoke, Porter was standing at his side.
     “How do you feel now, Eric?”
     “Weak,” said Brevis.
     Porter nodded. “It certainly took it out of you. But you’ll be pleased to know that whatever
you did was successful.”
     “You mean we’ve made it?” Brevis sat up. “We got back into congruence?”
     “As near as we can tell. When Sigmund and I came round we found we were in a simple
Gamma mode. We took the chance and dropped the ship out of Tau into real space. There we
found everything according to the catalogue. We’ve been taking spectroscope and
radio-telescope fixes on the identifiable primaries and radio-sources, and we’ve even
managed to establish our position.”
     “How did Pat make out?”
     “Fine. He recovered a lot quicker than you. He’s back in the blister right now doing
triangulation fixes for Sigmund, and feeling rather chipper about the whole thing. He estimates
we can make the return trip without losing congruence as long as we don’t tie our time
constant to a fixed point of reference.”
     “With that I agree,” said Brevis. “Our dimensional dilemma was a simple example of
Tau-psychic interaction. The radio-pulses controlled our instruments and our clocks. From
these we took our consciousness of time. It wasn’t a condition of time appropriate to the
separate universe we had become at that velocity, but we fondly imagined that time, at least,
was real.
     “It was our acceptance of that measured time which fixed it as a time constant as far as
Tau-space was concerned. All the other physical dimensions then had to adapt in order to
maintain the right mass-time relationship. I think for that we can steal Diepenstrom’s term of
an imagination trap—because that’s precisely what it was. Next trip just let the time constant,
and thus our time consciousness, drift with the ship. By the way, how far did we travel?”
     “When you feel up to it, Eric, come down to Control and see the scanners. It’s rather an
impressive sight. The Milky Way, seen from completely beyond its boundaries, is a rather
frightening and a rather nostalgic thing to see.”