The light of the miniaturizer had flashed on again after submergence and the fluid all about had turned into a glimmering opaque milk, but nothing followed that could be observed from within the Proteus.- If the opacity were spreading out and the ship shrinking further, there was no way of telling.

Grant did not speak in 'that interval of time, nor did anyone else. It seemed to last forever. And then the light of the miniaturizer went out and Owens cried out, "Is everyone all right?"

Duval said, "I'm fine." Cora nodded. Grant lifted a reassuring hand. Michaels shrugged slightly and said, "I'm all right."

"Good! I think we're at full miniaturization now," said Owens.

He flipped a switch which hitherto he had not touched. For an anxious moment, he waited for a dial to come to life. It did, with a dark and sharp 60 outlined- upon it. A similar dial, lower in the ship and visible to the other four, recorded the same.

The wireless rattled harshly and Grant sent back the ALL WELL. For a moment, it was as though some climax -had been reached.

Grant said, "They say outside we're at full miniaturization. You guessed correctly, Captain Owens."

"And here we are," said Owens, sighing audibly.

Grant thought: Miniaturization is complete but the mission isn't. -It's just beginning. Sixty. Sixty minutes.

Aloud, he said, "Captain Owens. Why is the ship vibrating? Is there anything wrong?"

Michaels said, "I feel it. It's an uneven vibration." "I feel it, too," said Cora.

Owens came down from the bubble, mopping his forehead with a large handkerchief.

"We can't help this. It's Brownian motion."

Michaels raised his hands with an "Oh, lord," of helpless and resigned understanding.

Grant said, "Whose motion?"

"Brown's if you must know. Robert Brown, an eighteenth century Scottish botanist, who first observed it. You see, we're being bombarded by water molecules from all sides. If we were full-size, the molecules would be so tiny in comparison that their collisions wouldn't affect. However, the fact that we're tremendously miniaturized brings about the same results that would follow if we had remained constant and everything in our surroundings had been greatly magnified."

"Like the water all around."

"Exactly. So far, we're not badly off. The water around us has been partly miniaturized with us. When we get into the blood-stream, though, each water molecule-on our present scale-will weigh a milligram or so. They will still be too small to affect us individually, but thousands will be striking us simultaneously from all directions, and those strikes won't be distributed evenly. Several hundred more might strike from the right than from the left at any given instant, and the combined force of those several hundred extra will shove us toward the left. The next instant we may be forced a bit downward and so on. This vibration we feel now is the result of such random molecular strikes.

"It will be worse later on. "

"Fine," groaned Grant. "Nausea, here I come."

"It will only be for an hour at most," said Cora, angrily. "I wish you would act more grown up."

Michaels said, with obvious worry, "Can the ship take the battering, Owens?"

Owens said, "I think so. I tried to make some calculations concerning it in advance. From what I feel now, I think my estimates weren't far off. This can be endured."

Cora said, "Even if the ship is battered and crushed, it's bound to stand up under the bombardment for a little while. If everything goes well, we can get to the clot and take care of it in fifteen minutes or less and after that it really doesn't matter."

Michaels brought his fist down on the arm-rest of his chair. "Miss Peterson, you are speaking nonsense. What do you suppose would happen, if we managed to reach the clot, destroy it, restore Benes to health and then have the Proteus smashed to rubble immediately afterward? I mean, aside from our deaths which I am ready to consider ignoring for the sake of further argument? It would mean Benes' death, too."

"We understand that," broke in Duval, stiffly.

"Your assistant apparently does not. If this ship were to be beaten into fragments, Miss Peterson, then when the sixty minutes - no, fifty-nine - are up, each individual fragment, however small, would enlarge to normal size. Even if the ship were dissolved into atoms, each atom would enlarge and Benes would be permeated through and through with the matter of ourselves and the ship."

Michaels took a deep breath, one that sounded almost like a snort. He went on, "It is easy to get us out of Benes' body if we are intact. If the ship is in fragments, there will be no way of flushing every fragment out of Benes' body. No matter what is done, enough will remain to kill him at de-miniaturization time. Do you understand?"

Cora seemed to shrink within herself. "I hadn't thought of that."

"Well, think of it," said Michaels. "You too, Owens. Now I want to know again, will the Proteus stand up under the Brownian motion? I don't mean only till we reach the clot. I mean till we reach it, finish it, and return! Consider what you say, Owens. If you don't think the ship can survive then we have no right to go on."

"Well, then," interposed Grant, "stop hectoring, Dr. Michaels, and give Captain Owens a chance to talk."

Owens said doggedly, "I came to no final opinion till I felt the partial Brownian motion we now experience. It is my feeling at the present motion, that we can stand up to sixty full minutes of the full pounding."

"The question is: Ought we to take the risk on the mere strength of Captain Owens' feelings?" said Michaels.

"Not at all," said Grant. "The question is: Will I accept Captain Owens' estimate of the situation? Please remember that General Carter said I was to make the policy decisions. I am accepting Owens' statement simply because we have no one of greater authority or with a better understanding of the ship to consult."

"Well, then," said Michaels, "what is your decision?"

"I accept Owens' estimate. We proceed with the mission." Duval said, "I agree with you, Grant."

Michaels, slightly flushed, nodded his head. "All right, Grant. I was merely making what seemed to me a legitimate point." He took his seat.

Grant said, "It was a most legitimate point, and I'm glad you raised it." He remained standing, by the window.

Cora joined him after a moment and said, quietly, "You didn't sound frightened, Grant."

Grant smiled joylessly. "Ah, but that's because I'm a good actor, Cora. If it were anyone else taking the responsibility for the decision, I would have made a terrific speech in favor of quitting. You see, I have cowardly feelings, but I try not to make cowardly decisions."

Cora watched him for a moment. "I get the notion, Mr. Grant, that you have to work awfully hard, sometimes, to make yourself sound worse than you really are."

"Oh, I don't know. I have a talen ..."

At that point, the Proteus moved convulsively, first to one side, then to the other, in great sweeps.

Lord, thought Grant, we're sloshing.

He caught Cora's elbow, and forced her toward her seat; then with difficulty took his own while Owens swayed and stumbled in an attempt to make it up the ladder, crying out, "Damn it, they might have warned us."

Grant braced himself against his chair and noted the Time Recorder reading to be 59. A long, minute, he thought. Michaels had said the time-sense slowed with miniaturization and he was obviously right. There would be more time for thought and action.

More time for second thought and panic, too.

The Proteus moved even more abruptly. Would the ship break up before the mission proper had even started?

Reid took Carter's place at the window. The ampule with its few milliliters of partially miniaturized water, in which the completely miniaturized and quite invisible Proteus was submerged, gleamed on the Zero Module, like some rare gem on a velvet cushion.

At least Reid thought the metaphor, but did not allow it to console him. Calculations had been precise and the miniaturization technique could produce sizes that would fully match the precision of the calculation. That calculation, however, had been worked out in the space of a few hurried and pressure-filled hours, by means of a system of computer programming that had not been checked out.

To be sure, if the size were slightly off, it could be corrected, but the time required to do so would have to come out of the sixty minutes-and it was going to be fifty-nine in fifteen seconds.

"Phase Four," he said.

The waldo had already moved above the ampule, the claw adjusted for horizontal holding, rather than vertical. Again the device was centered, again the arm dropped and the claws came together with infinite delicacy.

The ampule was held with the firm gentleness of a lioness' paw upon her unruly cub.

It was the nurse's turn at last. She stepped forward briskly, took a small case from her pocket and opened it. She removed a small glass rod, holding it gingerly by a flat head set upon a slightly constricted neck. She placed it vertically over the ampule and let it slide a small fraction of an inch 'into it, until air pressure held it steady. She spun it gently and said, "Plunger fits."

(From his upper view, Reid smiled in tight relief, and Carter nodded his approval.)

The nurse waited and the waldo lifted its arm slowly. Smoothly, smoothly, the ampule and plunger rose. Three inches above the Zero Module, it stopped.

As gently as she might, the nurse eased the cork base off the bottom of the ampule, revealing a small nipple centered on the otherwise flat lower surface. The tiny opening in the middle of the nipple was masked with a thin plastic sheet that would not stand up against even moderate pressure, but would hold firm against leakage as long as undisturbed.

Moving quickly again, the nurse removed a stainless steel needle from the case and adjusted it over the nipple.

"Needle fits," she said.

What had been an ampule had become a hypodermic needle.

A second set of claws swung out from the waldo and was adjusted to the head of the plunger, then clamped into place. The entire waldo, carrying the hypodermic needle in its two claws now moved smoothly toward the large double-doors that opened at its approach.

No human being could, with his unaided eyes, have detected any motions in the liquid so steadily transported by the inhumanly smooth movement of the machine. Both Carter and Reid, however, understood quite well that even microscopic motions would be nothing less than storm-tossing to the crew of the Proteus.

When the device entered the operating room and stopped at the table, Carter recognized this fact by ordering: "Contact the Proteus!"

The reply was: ALL WELL BUT A LITTLE SHOOK, and Carter forced a grin at that.

Benes was lying on the operating table, a second focus of interest in the room. The thermal blanket covered him to the collarbone. Thin rubber tubes led from the blanket to the central thermal unit under the operating table.

Forming a rough semi-sphere beyond Benes' shaven, grid-marked head were a group of sensitive detectors intended to react to the presence of radioactive emissions.

A team of gauze-masked surgeons and their assistants hovered about Benes, their eyes fixed solemnly on the approaching device. The Time Recorder was prominent on one wall and at this point it changed from 59 to 58.

The waldo stopped at bedside.

Two of the sensors moved from their place, as though they were suddenly endowed with life. Following the long-distance manipulations of a quick-working technician, they lined up on either side of the hypodermic, one adjacent to the ampule and one to the needle.

A small screen on the technician's desk woke to greenish life as a blip appeared upon it, faded, was reinforced,. faded again, and so on.

The technician said, "Proteus radioactivity being received."

Carter brought his hands together in a harsh clap and reacted with grim satisfaction. Another hurdle, one which he had not been allowing himself to face, had been overcome. It was not merely radioactivity that had to be sensed, but radioactive particles that had themselves been miniaturized; and that, because of their incredibly tiny, infra-atomic size could pass through any ordinary sensor without affecting it. The particles had, therefore, to pass through a de-miniaturizer first, and the necessary juxtaposition of de-miniaturizer and sensor had only been improvised in the frantic hours of the early morning.

The waldo holding the plunger of the hypodermic now pushed downward with a smoothly increasing pressure. The fragile plastic barrier between ampule and needle broke and, after a moment, a tiny bubble began to appear at the tip of the needle. It dropped off into a small container placed underneath; a second bubble and a third followed.

The plunger sank, and so did the water level within the ampule. And then, the blip on the screen before the technician's eyes changed position.

"Proteus in needle," he called out.

The plunger held.

Carter looked at Reid, "Okay?"

Reid nodded. He said, "We can insert now."

The hypodermic needle was tilted into a sharp slant by the two sets of claws and the waldo began to move again, this time toward a spot on Benes' neck which a nurse now hastily swabbed with alcohol. A small circle was marked on the neck, within the circle a smaller cross, and toward the center of the cross the tip of the hypodermic needle approached. The sensors followed it.

A moment of hesitation as the needle-tip touched the neck. It punctured and entered a prescribed distance, the plunger moved slightly and the sensor-technician called out, "Proteus injected."

The waldo moved off hurriedly. The cloud of sensors moved in, like eagerly-reaching antennae, settling down all over Benes' head and neck.

"Tracking," called out the sensor-technician, and flipped a switch. A half-dozen screens, each with its blip in a different position, lit up. Somewhere the information on those screens was fed into a computer, which controlled the huge map of Benes' circulatory system. On that map, a bright dot sprang into life in the carotid artery. Into that artery the Proteus had been injected.

Carter considered praying but didn't know how. On the map there seemed only the smallest distance between the position of the dot of light and the position of the blood-clot on the brain.

Carter watched as the Time Recorder moved to 57, then followed the unmistakable and rather rapid motion of the dot of light along the artery, headward and toward the clot.

Momentarily, he closed his eyes and thought: Please. If there is anything out there somewhere, please.

Grant called out, having a little difficulty catching his breath. "We've been moved toward Benes. They say they're getting us into the needle and then into his neck. And I've told them we're a little shook. Whoof - a little shook!"

"Good," said Owens. He battled with the controls, trying to guess at the rocking motions and neutralize their effect.

He wasn't very successful.

Grant said, "Listen, why - why do we have to get into the - oof - needle?"

"We'll be more constricted there. Moving the needle will hardly affect us then. Another-uh-thing, we want as little of the miniaturized water pumped into Benes as possible."

Cora said, "Oh, dear."

Her hair had fallen into disarray and as she tried, futilely, to move it back and out of her eyes, she nearly fell over. Grant tried to catch her but Duval had her upper arm in a firm grip.

As suddenly as the erratic rocking had started, it ceased.

"We're in the needle," said Owens with relief. He turned on the ship's outer lights.

Grant peered ahead. There was little to see. The saline solution ahead seemed to sparkle like a dusting of dim fireflies. Far up above and far down below was the distant curve of something which shone more brightly. The walls of the needle?

A quick sense of worry nagged at him. He turned to Michaels. "Doctor..."

Michaels' eyes were closed. They opened reluctantly and his head turned in the direction of the voice. "Yes, Mr. Grant."

"What do you see?"

Michaels stared forward, spread his hands slightly, and said, "Sparkles."

"Do you make out anything clearly? Does everything seem to dance about?"

"Yes, it does. It dances."

"Does that mean our eyes are affected by the miniaturization?"

"No, no, Mr. Grant." Michaels sighed wearily, "If you're worried about blindness, forget it. Look around you here in the Proteus. Look at me. Is there anything wrong with how it looks in here?"

"No."

"Very well. In here, you are seeing miniaturized lightwaves with an equally miniaturized retina and all is well. But when miniaturized light-waves go out there into a less-miniaturized or completely unminiaturized world, they are not easily reflected. They're quite penetrating, in fact. We see only intermittent reflections here and there. Therefore, everything out there seems to flicker to us."

"I see. Thank you, doc," said Grant.

Michaels sighed again. "I trust I get my sea-legs soon. The flickering light and the Brownian motion together are giving me a headache."

"Here we go!" cried Owens, suddenly.

They were sliding forward now, 'the sensation was unmistakable. The far-off curving walls of the hypodermic needle seemed more solid now as the spotty reflection of miniaturized light from their walls blurred and melted together. It was like riding a roller-coaster down an infinite incline.

Up ahead, the solidity seemed to come to an end in a tiny circle of flicker. The circle enlarged slowly, then more rapidly, then yawned into an incredible abyss-and all was flicker.

Owens said, "We're in the carotid artery now." The Time Recorder read 56.