The ten bodyguards marched with stiff deliberation to join their fellows already standing in front of the bulkhead. They clumped along two by two, the leading pairs carrying Niger and Rufus; and one of the last pair carried a shield, just as the file-closer had said.

It seemed to be an ordinary legionary's scutum of leather-covered plywood, twice as high as it was wide and slightly convex on the side toward the enemy. The rim was bound with bronze strips, and there was a rectangular boss of the same metal bulging out sharply to give room for the hand of the man carrying it.

Neither the boss nor the shield-facing had any of the fancy work, heraldic engraving and appliqued geometric designs, which distinguished the equipment Crassus' army carried into Parthia. Structurally the shield appeared to be the same, and the way Niger's arms flexed when the guard handed it to him showed that the piece was of at least the usual weight.

The guards who held Niger released the young Roman's arms so that he could take the shield. One of them boomed something to him, probably in Latin, but Vibulenus heard it only as a rumble of sound. Niger's brow knitted as he tried vainly to make sense of the order.

Clodius Afer's hand was back on the tribune's shoulder in a gesture of comradeship rather than control. The two men were blank-faced because they had dissociated their intellects as completely as possible from their bodies and from the memory that would flesh out the data their eyes were receiving.

Two of the armored guards stood close to Niger, near the corner formed with the front wall. Legionaries on that side of the room shifted so they were farther from the comrade snatched from among them than they had been from the original line of guards.

"There's five thousand of us, aren't there?" said Vibulenus softly, rationally. "Well, less after this morning, maybe." But Arrius Crescens stood, open-eyed and stolid, no longer a subject of fear in the midst of newer uncertainties…

"And there's twenty of them," the tribune went on. "Twenty-one, yes…"

The file-closer's hand tightened enough to remind Vibulenus that they would wait and watch, the two of them.

Rufus and the guards directing him marched toward the Commander who stood slim and aloof with the bulkhead behind him and the legion in front-the one with no more volition than the other.

The blue figure glanced toward Niger and perhaps spoke something into his ears alone. The young legionary raised the shield over his head, holding it by the lower rim so that the soft highlights of the boss were toward the Commander. The shield wavered a little; Niger steadied it and himself by backing a step to the sidewall and bracing his shoulder there.

"Our own weapons-those of my guild," said the Commander as his shimmering eyes swept the legion again, "are of greater destructiveness than even this demonstration will prove. Nevertheless, watch the shield which your fellow is holding."

While the Commander spoke, his hands swung forward a black cylinder slung behind him, visible but unremarkable in this interval that held so many remarkable things. The cylinder was about the length and diameter of the Commander's forearm. The irregularities on it, including the handles by which the Commander raised the device to his shoulder, gave it the look of plumbing which should have been decently hidden behind stone facings or molded bronze.

The guards holding the other Pompilius cousin halted near the Commander-behind him, actually, now that he was facing the side-but the blue figure ignored them. There was a glitter in the air above the cylinder, something that could have been static electricity but suggested an image of the shield toward which the cylinder was aimed.

A jet of light so cohesive that Vibulenus thought it was a fluid spurted from the cylinder to the shield. The boss exploded in a fountain of green sparks as the flash-heated metal burned in the air. Niger was one of a hundred men who screamed in surprise. He flung the shield away from him as drops of molten bronze spattered twenty feet in every direction.

The shield hit the floor, walking on its rim in a slow pirouette before clanging down on its convex face. The hole burned through the boss was large enough to pass a clenched fist. Strips of wood glued to form the shield's core sprang outward at the edge of the burned metal so that they looked like ravelled ends of rope.

Pompilius Niger bolted back into the mass of legionaries from which he had been taken. None of the guards tried to stop him-but Rufus found, when he made a similar attempt, that his arms were still held firmly.

"When I or any employee of my guild give you an order," said the Commander with his usual cool precision, turning toward his audience again, "you must obey instantly and utterly."

He released the cylinder. It snuggled itself to his back, out of the way but quickly available at need.

Charred wood and burning felt created a musty reek in the atmosphere as the shield continued to smolder.

"He wasn't carrying it outside this building, though," said the file-closer thoughtfully, while his fingers gently kneaded the muscles of Vibulenus' shoulder.

"The shield will remain here after this assembly," said the Commander. "I had intended to have your fellow carry it among you himself, but I underestimated the effect our weapons would have on warriors of your- cultural level."

"Little bastard," whispered Clodius Afer because the Commander's voice in his ears had hinted at amusement.

"Maybe they can't use anything but, but maces outside this ship," the tribune murmured to the veteran. "Maybe their gods would strike them down for violating that law."

Though why would there be such a law?

"Almost the whole of the ship is yours to roam as you please," continued the Commander, "except when you are summoned for training or assembly. This bulkhead-"

He stretched out one delicate, overfingered hand to tap the shifting pastels of the bulkhead behind him "-is my territory and that of my crew and guards. You are not to attempt to enter it, and you are not to approach within three feet of its surface. If you do- watch closely, now."

Vibulenus was watching the Commander's hands, expecting one of them to reach back for the cylinder. The blue figure did not move at all.

Two of the guards flung Pompilius Rufus toward the bulkhead.

The boy did not thump against the lighted metal because his body disintegrated in the air with a tearing crash.

The Commander winced an instant before the noise erupted behind him, and his shoulders hunched against the sauce of pulverized body spitting back into the room.

There was a barrier three feet from the visible wall. The momentum of Rufus' body carried him against it, and the young legionary splashed across the plane of contact as if he had fallen from a high cliff. Bone and muscle, as fluid and finely divided as the blood with which they merged, squirted sideways in a vertical tapestry behind the Commander, thinning and disappearing ten or a dozen feet from the center of impact.

Occasional globules overloaded what was an almost instantaneous process of digestion. Those caused the pops and sputters that threw droplets as high as the ceiling and as far as the middle rows of men watching the demonstration.

The tribune's forehead felt damp. He wiped it with his palm, then wiped his palm on his tunic, telling himself as he did so that it was sweat.

He felt no urge to attack the Commander. In fact, his guts were filling with ice water and his legs began shaking so violently that he was afraid he would fall down.

"This is not something I or my subordinates do, you understand," said the Commander in the chill tones of nightmare, his words heard clearly throughout the Main Gallery despite the gasps and cries of the men assembled there. "It is something that happens automatically to anyone who steps close to the wall. Only those whose nerve patterns have been keyed into the- mechanism of the ship-can survive."