Aud shook his head again. “We’ll just have to take our chances. I can’t spare a man. And none of these people can handle dynamite.”

I said, “I can.”

“ON THREE!” Aud and I, in line with twenty others, strained against a cable spooled through a block and tackle stripped from the camp machine shop, tied to an eyelet on an ice sledge. The sledge’s runners squealed, then groaned as the great iron box crashed onto its side like a dying mammoth. The echoes died against the canyon’s stone-cold walls, even as other cars toppled by others of the three hundred volunteer shopkeepers fell into place.

We were overturning sledges so that their iron floors became parapets that blocked the canyon bottleneck from vertical stone wall to vertical stone wall. Aud set the first line of our barricade six hundred yards up the canyon, near its crest, where the thousand-foot-high walls bottle-necked down to a twenty-yard width.

That way the front line of an entire division of attacking troops, even shoulder to shoulder, could never amount to much more than sixty soldiers. And those sixty would be advancing uphill, unprotected, for six hundred yards. Meanwhile, our guys, even if they weren’t marksmen, would hunker behind cover and mow their attackers down, then mow down the ranks behind them, until we ran out of ammunition or the attackers ran out of enthusiasm.

There’s a schoolyard simplicity to infantry tactics once you remove air power from the equation.

Boom.

The last sledge toppled across the canyon like a beached whale as Aud stepped alongside me, batting dust off his long coat with mittened hands. He craned his neck, up along the canyon’s east wall, where the narrow ledge overlooked both us and the plain to the south from which the attack would come. He sighed. “There’s no point in placing marksmen above. We have no marksmen but you.”

“I’m taking a rifle and a hundred rounds up on the ledge with me.”

Aud shook his head. “Your most vital job is to destroy the flanking route, not to play at target practice. Just set the charges, light the fuses, and run. Live to fight another day.”

I looked around. Men stacked rocks on the parapets. Others cleaned weapons or unboxed cartridges. Each shopkeeper busied himself to avoid the reality that they would die in this canyon. “Nobody else seems to have an exit strategy.”

I knelt, then swung up the pack with the dynamite. Aud grasped the pack’s handle, centered the load on my back. “Jason, I know you. You intend to return from the pass, then rejoin us here. You return to the camp. If the stones aren’t delivered, this sacrifice will count for nothing. Honor me, and these men, by making sure we all died for something. Promise me that.” He laid a hand on my shoulder.

I laid my hand over his, stared up at the late afternoon sky. “I better go. The only thing I hate worse than heights is climbing them in the dark.”

It might once have taken me a few hours to make my way back north along the canyon, then east to the steep, narrow route that switched back and forth toward the ledge that overlooked the canyon, then up the trail that climbed a fifth of a mile.

By the time I not only made it to the trailhead, then climbed to the ledge, my skinned knees and elbows trembled beneath my coat’s sweaty bulk, and the cotton that had once been saliva crusted my lips, and it was midnight, according to the Tressen pocket watch I carried. The only Spooknet-capable ’Puter the Spooks would allow us I had left behind with Jude, so that he could call for pickup of the Cavorite in case I didn’t make it back.

I lay on the ledge in the dark, too exhausted to fear the sheer drop that began inches from the blisters inside my boots.

I had no heated armor to keep my fingers and toes from going numb, no helmet water nipple, no padding when I slipped and fell, and no optics to keep the dark from blinding me. I huddled in a crevasse, snugged my clothes up to keep as warm as I could, and dozed.

I woke at four a.m.

The moonless Tressel night was frigid, black, and still.

Except for a faint glow on the southern horizon that shifted position back and forth. Like a train winding north.

WITHOUT NIGHT-VISION EQUIPMENT, I had to wait for dawn to begin my work. I was in no hurry. Among the things that had terrified me since childhood were heights and explosives.

My hands shook as I stuffed black-powder-cored fuse lengths into dynamite sticks. I had to take off my long coat and mittens to scramble down the rock face below the narrow ledge, wedge the old dynamite into cracks and joints in the granite, then pay out fuse to the place from which I would light it.

If I had done it right, a fifty-foot section of the ledge should shear away, so no infantry could either slip behind or get an angle to fire down on Aud’s unlikely Spartans.

By the time I finished, I couldn’t feel my fingertips.

I sat rubbing back the circulation while I stared toward the horizon, where the train’s glow had shone in the early-morning darkness. I focused on the quivering image of a tiny black worm against a white sea. The troop train was perhaps an hour away. I shouted a warning down to the defenders.

If it were spring, or even winter, there might be enough snow on the rock above the canyon for my shout to trigger an avalanche. That happens in the holos, not in real life.

I inched south along the ledge, cringing from the edge, until I found a notched boulder from behind which I had a clear field of vision and of fire over the train track and adjacent avenue of approach.

I had promised Aud-technically, I had avoided promising, but that was semantic crap-that I would return to camp, not to the canyon floor. I didn’t promise him when.

I loaded the rifle, a bolt-action Tressen standard, with a telescopic sight that was little more than lenses fitted in a tube bolted above the receiver that was as long and slender as a walking stick. Then I laid out ammunition on the rock ledge in front of me.

The train showed clear now. It streamed oily smoke that scudded above the flat whiteness, and it slithered closer minute by minute.

Sound echoed up crystalline from the canyon floor. Rifle bolts snicked, a dropped cartridge case jingled over rock. Voices whispered and prayed.

From my vantage, I could see the train. But an observer on the train wouldn’t be high enough to peer into the canyon’s shadows and see the blocked path. Minutes crawled by before the troop train visibly slowed.

When the train finally stopped, I estimated the range to the engine, an iron hedgehog with its great spiked wheels, at two thousand yards. If our attackers had bothered to bring artillery, they could have stood off and simply shelled the canyon. Our first tactical victory had been won for us by our opponent’s disdain.

A single patrol emerged from the first coach behind the engine’s oil tender and advanced along both sides of the ice trail.

I sighted the rifle not on the patrol, which was well out of range, but on the trench that we had dug to block the ice road to the canyon. An army could fill a trench fast, but not so fast if the trench was covered with aimed fire. Four hundred clear-shot yards away from and below me, the enemy wouldn’t be able to repair the trench as long as I kept sniping his repair crews. But our main purpose was not to kill repairmen but to prevent our enemy from using the train as an armored approach vehicle, or worse, as a battering ram.

We needn’t have worried. The train was Forty-fifth Division’s ride home. Their commander wasn’t about to put it in harm’s way. I swore to myself and wished for artillery, for a smart bomb, even for enough explosives to have improvised a train mine out there on the plain.