Sam sucked in her breath. “What d’you mean?” She took the card from me. “Who is this?”
“Your grandfather.”
“My grandfather.” She shook her head, confused. “You mean the guy who did that movie?”
“The very same. Unless someone else ripped off his BSC card. In which case, they made a very bad mistake.”
“But how would they get him in here? I mean, the door—”
She shone her torch on the crescent-shaped entrance to the chamber. “It was blocked—you saw that stone. Nobody could have moved that, not without an excavator.”
“Sure they could. They built the pyramids, right? They built this place. Someone could’ve brought the stone in with a wagon, maybe even a big wheelbarrow.
“Or maybe it was already here. All you’d need would be a fulcrum, some kind of wedge. You could raise it with rollers on planks. It might take a while, but out here you probably have a lot of time on your hands. One person could do it, if they weren’t in a hurry.”
“But wouldn’t he escape?”
“Not if he was knocked out or drugged.”
“But…” Sam stared at me, bewildered. “Why?”
“Why would someone kill those babies?”
She gazed down at the skeleton, biting her lip, and looked at me again. “Because they were his?”
“Great minds think alike. That would be my guess.” I tucked the card into my pocket. “We better go. It’s getting late.”
“No!” Sam grabbed my arm, pointing at the far side of the chamber. “What I wanted to show you is just there. It’ll only take a minute. You need to see it while the sun’s out.”
I started to pull away, but stopped. Faint light glimmered on the wall that Sam had indicated: another doorway. That might mean that this portal opened onto a chamber that led outside.
I nodded. “Okay. But be quick.”
We crossed the chamber in a dozen steps, a solitary whelk crunching under my boot. I halted beside Sam, just inside the doorway. My head grazed the stone lintel as I followed her into the next chamber.
Unlike the circular room where Leith Carlisle had been immured, this one was long and narrow, ten feet wide and twice as long. After the dark passages and dim chamber behind us, it seemed painfully bright.
And cold. At one end of the chamber, there was an opening in the wall, six inches square and shoulder height from the floor—a window or light well. I could glimpse stones silhouetted black against a brilliant gold square of late-afternoon sky, and hear the unearthly moan of wind from atop Carn Scrija.
“This is what I showed you.” Sam hurried to the opening and stood on her toes to peer out. “When we were out on the moor. This is where the rocks tumbled down the hill, so I could see the window.”
The wind lashed her black hair from her face. For an instant she looked like Adrian, gazing out at the colossal stones that loomed above Salisbury Plain. Then she turned to me once more.
“Be careful,” she warned, and headed toward the opposite end of the chamber. “Ground’s wet where the rain and snow got in.”
The damp was restricted to the area beneath the window, where it had seeped into the packed earth, leaving a dark square like a shadow on the floor. I glanced outside then went to join Sam. She’d stopped at the midpoint of the narrow room.
“Look,” she said.
From the floor rose an immense heap of whelk shells. At its highest, the pile came up to my thighs, sloping from the wall for a distance of three feet. Then it settled into an ankle-deep mound that ran along the wall for several yards, until the pile devolved into random shells scattered across the floor.
I picked up one. It was slightly larger than the whelks Sam had bashed to a pulp on the freezer. Glancing at the midden, I saw that all of the whelks were about two inches in length. They’d been selected for uniform size. I stooped and ran my hands through the mound, letting shells fall between my fingers in a hail of dull blue and gray.
None of these whelks had been crushed. Instead, they’d all been broken in the same place—the last whorl of spiral near the top. I ran my thumb along the edge of one, touched the slender central spire from which the outer shell radiated. The dye would have been extracted from a gland in here: cracking open the shell at just the right point would have exposed the tiny sac.
You’d need hundreds—thousands—of shells to extract enough mucus to make a dye or emulsion. Here in the fogou, there might have been tens of thousands, or more.
I thrust my hand into the midden and dragged it through the shells until at last I touched the floor. I leaned into the heap, heedless of the miniature avalanche of whelks that pelted me, inching my fingers across the floor until they brushed against something flat and solid. With a grunt, I dug my hands beneath it.
“What is it? Can I help?” Sam appeared at my side, her face flushed, and began scrabbling at the bottom of the heap.
“Be careful,” I said. “I don’t want all this falling on me.”
Soon I was able to wedge both hands beneath the object buried inside the mound. I grasped the edge tightly and slowly pulled it toward me. Shells cascaded around us as I drew it out.
I sank to the floor, catching my breath, and set the object in my lap. A flat stone, the size and shape of a small flagstone. Sam stared at it in disgust.
“It’s a fucking rock,” she said.
“No.” I bent to blow across the surface. “It’s an anvil.”
Grit from crushed shells stung my eyes as I swiped my sleeve across the stone, then bent my head to inhale deeply. My nostrils flared as I caught the ghostly scent of garlic. I looked up at Sam.
“See if you can find a rock in here. Something small enough to fit in one hand.”
She hopped up and paced the room, examining the floor. After a few minutes I shook my head and pointed at the midden.
“Probably it’s buried under there,” I said. “Forget it.”
“Wait—like this?”
She scooped something from the ground and handed it to me. “It’s just another rock.”
I turned the fist-sized stone over in my hands. It was oblong, rust-colored. “Yeah, but look here.” I tapped the stone with a finger. “See how it’s abraded there? Someone used this to break the shells. And he broke them all at the same place—see?”
I tossed a whelk at her. She caught it and examined it dubiously.
“That’s where the dye sac was,” I said. “Someone had a whole little factory operation here, cracking those open and removing the glands.”
Sam inclined her head toward the midden. “That’s why I wanted you to see it—all those shells. When you showed me that down by the farm, how the slime changed colors. But what would they use them for?”
I placed the flagstone on the floor and stared at it. I licked the tip of my index finger and pressed it, hard, against the stone, let it remain there for a long moment. I drew my finger to my mouth and touched it to the very tip of my tongue.
It tasted of salt.
“Shit.”
I looked at Sam in amazement, then scrambled to my feet. I turned to face the far end of the chamber, and the rock wall directly across from the window.
A second window appeared to be inset within the granite: a foreshortened square of sunlight, cast from the opening in the opposite wall. The bright square aligned almost perfectly inside a square of pale granite that was finer-grained than the surrounding stones and flecked with glittering mica.
The center of this granite slab appeared to have been smudged with broad bands of ash or charcoal, like a Rothko painting done in shades of gray. There were oddly shaped flaws in this darker substrate.
Very slowly I walked toward the wall, stopping when I was a foot away. I glanced back.
Light from the window formed a horizontal shaft that pierced the dim chamber, ending in that bright square on the granite wall. I angled myself so my shadow wouldn’t fall across the sunlit square. My entire body prickled with gooseflesh.
Small luminous impressions were scattered across the granite, so faint I might almost have imagined them. Tiny arrowheads designed to fell a sparrow. A scallop shell. A blade-shaped leaf.
And, in one lower corner of the square, a curving line that might almost have been a flaw in the rock.
Only it wasn’t. The line traced part of a human profile: nose and upper lip and chin: the bright shadow of a face. Again I licked my finger and pressed it against the stone, drew it to my mouth and tasted salt. Sam crept up beside me and touched my arm.
“What is it?” she whispered.
I let her lean into me. It was a long time before I answered. When I did, my voice shook.
“That window behind us? It’s an aperture. Whoever made this chamber knew exactly what they were doing.” I looked down into Sam’s white face. “We’re standing inside the world’s oldest camera obscura.”