against enemies making their way down it. He started to think about what he would put in place if he had been in charge of such matters.
His thoughts were interrupted when he collided softly with the back of the man in front. The man behind him piled into his back, too, and so on down the line as they came to a halt, almost without a sound.
“A gate?” the subaltern whispered. Looking ahead, over the shoulder of the man in front, Vatueil could just make out a broad grating filling the tunnel ahead. The single lamp was turned up a little. The water sieved itself between thick bars of what appeared to be iron. There was more whispering between the captain and the subaltern.
The tunnellers were called forward and were confronted by the grating. It was locked shut against a stout, vertical iron stanchion immediately behind. It looked like it was designed to hinge back towards them and then up towards the ceiling. A strange arrangement, Vatueil thought. All three tunnellers were ordered to light their lamps, the better to inspect the lock. It was about the size of a clenched fist, the chain securing it made of links thick as a little finger. It looked rusted, but only slightly.
One of the other tunnellers lifted his pickaxe, testing his swing and where the point might strike to break the lock.
“That will be noisy, sir,” Vatueil whispered. “The sound will travel a long way down the tunnel.”
“What do you suggest, bite it?” the younger officer asked him.
“Try to lever it off with the pry bar, sir,” he said.
The senior officer nodded. “All right.”
The tunneller with the pry bar brought it over his shoulder and wedged it under the lock while Vatueil and the other miner held it out from the grating, angling it just so to increase the effect, then, once their comrade had taken the strain, joining him to pull hard on the end of the bar. They strained for a few moments to no effect beyond a faint creaking sound. They relaxed, then pulled again. With a dull snap and a loud clank the lock gave way, sending the three of them falling backwards into the water in a clattering tangle. The chain rattled down into the water to join them.
“Scarcely quiet,” the subaltern muttered.
They picked themselves up, sorted themselves out. “No sticks or branches or anything against it,” one of the other men said, nodding at the foot of the grating.
“Settling pool further back,” another suggested.
Through the grating, Vatueil could see what looked like stony blocks in the path the water took beyond, like square narrow stepping stones filling the base of the tunnel. Why would you put those there, he wondered.
“Ready to raise it?” the captain said.
“Sir,” the two tunnellers said together, taking a side each, arms thrust into the dark water to pull at the foot of the grating.
“Heave, lads,” the officer told them.
They pulled, and with a dull scraping noise the grating hinged slowly up. They shifted their grip as it rose and pushed it towards the ceiling.
Vatueil saw something move on the ceiling, just behind the slowly moving grille. “Wait a moment,” he said, perhaps too quietly. In any event, nobody seemed to take any notice.
Something – some things, each big as a man’s head – fell, one glinting in the lamp light, from the ceiling. They smashed on the edges of the raised blocks beneath and dark liquid came pouring out of them as their jagged remains vanished into the moving water. It was only then that the men hauling up the grating stopped; too late. “What was that?” somebody asked. The water around the blocks, where the liquid had entered, was bubbling and fuming, sending great grey bubbles of gas to the surface of the water, where they burst, producing thick white fumes. The gas was rising quickly into the air, starting to obscure what view there might have been down the tunnel beyond.
“It’s just …” somebody started, then their voice trailed away.
“Back, lads,” the