Three-Quarters of an Inch of Iron

"Every prison is built by someone who understood exactly how a person would try to leave it."

The shutters held.

Roderick tried them all, one after another, in a cold methodical rage that Thalessa could only admire. He tried the door with a lever of splintered stool-leg and a wedge of brandy flask. He tried the arch to the cave with the heavy iron stand from the twenty-first lamp, swinging it in both hands like a ram, until the plate rang like a gong and his arm shook with the shock of it. He tried the walls. He tried the stone slab that closed the secret stair, and the seams of the floor, and the places where the roof curved into the wall.

Nothing gave.

By the time he stopped, the smell had changed. It was no longer a faint wrongness at the edge of the nose. It was a taste. It lay on the tongue like a coin, sour and metallic and strange, and when she breathed it she felt a thin prickling burn behind her eyes.

"Here," she said, and held out the mask.

"I don't need it."

"You are coughing."

"I'm clearing my throat."

"You're coughing blood, Inspector, and you know it." She pushed the folded cloth into his hand. "Hold it to your face. Breathe through it. It tastes foul but it will keep the worst out."

He looked at her. The sweat had run down his face in streaks through the dust. His left arm hung loose in its sling and the bandage on his shoulder had bled through again, a spreading rust-red stain. He was gray to the lips.

"It won't open," he said hoarsely.

"I know."

"It is three-quarters-of-an-inch plate. Wrought. Hung on pivots in the rock. I've looked at the hinges, there are none, it's cast into the lintel. It was made by someone who knew what a hinge was for and decided to leave it out."

"I know."

"If I had a sledge. If I had a cold chisel. If I had a day."

"You have eighteen minutes."

He looked at her. Then, to her astonishment, he laughed, a short cracked bark.

"You're enjoying this," he said.

"I am not."

"A little."

"A very little." She put the mask to his face with her own hand and held it there. "It is the only part of the situation that is amenable to analysis. Breathe."

He breathed.

…

They gathered at the table, the three of them, standing among the burning jars.

The haze had thickened. It lay across the vault now in a gray veil at about the level of the knee, and it rolled and shifted as the air moved, creeping slowly outward from the vents along the floor. The lamps burned steadily above it, twenty-one small golden flames, but the light they gave had grown yellow and dim, and the farthest end of the crypt was lost.

Thalessa wore her mask round her neck, ready, a pad of grayed linen on a loop of the tablecloth hem. Vespera wore hers already. She stood at the end of the table in her gray dress and white apron with a wet cloth tied over the lower half of her face, so that only her eyes showed, and those were fixed and dark and strangely steady.

"There is one thing," she said.

"Tell us."

"I did not think of it before." The words came muffled through the cloth. "It did not seem to matter. I was not going to use it."

"What?"

"The lantern."

Roderick frowned. "The lantern?"

"In the roof." She pointed, with a hand that was almost steady. "At the seaward end, over the arch. Where the vault ends and the cave begins. There is a place in the ceiling that is not stone."

They looked.

At first Thalessa saw only the roof: black basalt, streaming with brine, hung with its curtains of white crystal. Then her eye caught a pale gleam, high up, at the very limit of the lamp-glow, over the sealed arch. It was a disc about the size of a dinner plate, set flush in the rock, faintly greenish, faintly translucent. It glimmered like a coin at the bottom of a pool.

"Glass," she said.

"Glass. Three inches thick. A lens." Vespera nodded. "The smugglers made it, a hundred and fifty years ago, for a signal. There's a shaft behind it. It goes straight up through the cliff. It's forty feet, or perhaps forty-five, and it comes out in the floor of the old watch-house, under the hearth. They used to light a lantern at the top, and the glow would come down the shaft and shine in the crypt, and the men in the boats could see it from the cave."

"The watch-house," said Roderick.

"On the cliff. The ruin."

"I've been in it." His voice was suddenly alert. "Thalessa stitched me there. The hearth was heaped with gulls' nests. There was a flagstone."

"That's it. It's laid loose over the mouth of the shaft. A man could lift it from below, with a bar." She swallowed. "I covered the lens with tar, last winter. Because it let in a light at night, when the moon was up, and I was afraid of it. I painted it over from the cave side, from a boat."

"Can it be broken?"

"The glass? With an iron bar, if you could reach it. But it's thirty feet over the floor. There's nothing to stand on."

"Rope?"

"There's none."

"The tablecloth."

"It's linen. It would never bear a man's weight." She hesitated. "And the salt. You couldn't climb it. The columns are slick as glass."

Thalessa had gone quiet.

She stood with her head tilted, her eyes on the pale green disc in the roof, her lips moving silently. It was a look Roderick knew. He had seen it twice before: once at the bedside of Ragnar Sterling's corpse, and once on a ladder in the dark. He waited.

"The gas is heavy," she said at last.

"Yes."

"It sinks. It pools. It fills the low places first, the floor, the stair, the cave. In a sealed room, it fills from the bottom up, like water in a bath. By the time it reaches the roof, it will have filled the whole vault."

"That's what you said."

"Yes. But it is also dense. It is a column. If I open a door at the top of that column, it will not flow out. It will stay where it is." She frowned. "Unless there is a draft."

"The shaft."

"Forty-five feet of it, vertical, with an opening at the top into the open air. On a cold night, with the wind rising." She turned her head. "Roderick, how cold is it outside?"

"Cold."

"Very cold?"

"It was snowing at dusk."

"Then the air in that shaft is far colder than the air in this vault. The vault is warm. The lamps, the breath, the furnace. Warm air rises. Cold falls." She spoke faster. "A chimney draws. If I open the top of the shaft, the warm air in the crypt will rush up it like smoke up a flue. And it will pull the gas with it."

"Pull it up."

"Pull everything up. Out. Into the night."

"And us?"

"We should have air. At the cost of a freezing wind down the shaft." She was breathing quickly. "It would give us time. An hour, two hours. Until the furnace burns out. Until the tide falls and the cave can be unsealed. Until someone knows we are here."

"No one knows."

"No one," she agreed. "But there is still the lens."

Roderick was looking at the roof.

It was an enormous distance. In the gold dim light the vault seemed to climb like a cathedral, black and streaming and hung with its icicles of salt. The pale disc was a faint green moon, remote and unreachable, over the arch. Between it and the floor there was nothing at all.

"Thirty feet," he said.

"Thirty-two, to be exact. I measured it."

"A man can't fly."

"No."

"Then he must climb." He rubbed his chin, leaving a black smear. "What is there to climb?"

"The columns."

"You said they were slick."

"They are slick with brine. But the brine is only a film." Vespera's eyes had narrowed. "Underneath, they are rough. It is crystal. It has edges. If one had gloves, and something to grip with, and—"

"I've no gloves," said Roderick, "but I've two good hands."

"You've one."

"I've one good one. And one that holds." He flexed his right fist. "Thalessa, bring me the lamp-stand."

…

She watched him prepare.

He did it as he did everything, with a kind of grim economy. He took off his coat, and his sling, and his waistcoat, and stood in his shirtsleeves in the golden dusk, rolling his sleeves above the elbow. The bandaged shoulder was a ruin of rust-colored cloth. She wanted to cry out. She said nothing.

He took the iron lamp-stand, a rod as thick as his thumb, three feet long, with a flat base, and slung it across his back with a strip of linen. He tore the hem from the tablecloth, and wound it round both hands, thickly, and knotted it at the wrists. He looked at the nearest column, a fat white spear of crystal that rose from the floor beside the arch to the roof, and tested it with his palm. It was wet. It glittered.

"You cannot do this," said Thalessa.

"I'm going to do it."

"Your shoulder."

"It's not broken."

"It is torn open, and I stitched it, and every stitch will rip." She caught his sleeve. "Roderick. If you fall."

"Then I fall."

"Thirty feet. On stone."

"Then you will have an extremely interesting autopsy." He turned to face her. His eyes were bright, and clear, and a little mad. "Thalessa. You told me that there is always an antidote. I'd like to be the thing that opens the window."

She stared at him.

Then, with a gesture that surprised them both, she took his face in her two hands and kissed him on the mouth, hard, quickly, with the iron taste of the gas on both their lips.

"If you die," she said, "I shall never forgive you."

"I'll bear it in mind."

"I mean it."

"I know." The ghost of a smile. "Mask."

She tied it over his face. Her fingers shook. She drew the knot tight at the back of his neck, and smoothed the cloth over his nose, and stepped back, and looked at him, a tall gray shape in the flickering gold, with the iron stand on his back and the white bandages on his hands.

Vespera had been watching in silence.

She came forward now, slowly, and stood beside Thalessa. Her wet cloth hid half her face. Above it her eyes were enormous.

"Inspector," she said.

He turned.

"I'm sorry," she said.

"You will tell me that at the trial."

"I may not—"

"You will." His voice came muffled through the linen, but steady. "You'll tell me at the trial, and I'll stand in the box, and I'll tell the court you saved my life by remembering a skylight." He put out his hand. For a moment she hesitated. Then she took it. "Hold the lamp," said Roderick. "I'd like to see where I'm going."

He turned to the column.

He set his hands against it. He set one foot, and then the other, on a knob of crystal at the base. He drew a deep breath, and exhaled, and began, slowly, painfully, with a wet slithering rasp, to climb.