Tunnels 02, Deeper

over the tops of her shoes, she hopped back onto the bank, which was carpeted with a springy green pad of sheep-cropped grass. Still she maintained the same unrelenting pace and, before long, a rusted wire fence came into view, then the raised farm track that she knew ran behind it.
    She spotted what she'd come for: Where the farm track intersected the stream there stood a crude stone bridge, its sides crumbling and badly in need of repair. Her course beside the stream was taking her straight toward it, and she broke into a trot in her haste to get there. Within minutes she had arrived at her destination.
    Ducking under the bridge, she paused to wipe the moisture from her eyes. Then she crossed to the other side, where she held completely still as she studied the horizon. The evening was drawing in and the rose-tinged glow of newly lit streetlamps was just beginning to filter through a screen of oak trees, which hid all but the tip of the church steeple in the distant village.
    She returned to a point halfway along the underside of the bridge, stooping as her hair snagged on the rough stone above. She located an irregular block of granite, which was slightly proud of the surface. With both hands, she began to pry it free. It was the size and weight of several house bricks, and she grunted with the effort as she bent to place it on the ground by her feet.
    Straightening up, she peered into the void, then inserted her arm all the way to her shoulder and groped around inside. Her face pressed against the stonework, she found a chain, which she tried to pull down on. It was stuck fast. Tug as she might, she couldn't move it. She swore and, taking a deep breath, braced herself for another attempt. This time it gave.
    For a second, nothing happened as she continued to pull one-handed on the chain. Then she heard a sound like distant thunder emanating from deep within the bridge.
    Before her, hitherto invisible joints broke open with a spray of mortar dust and dried lichen, and an uneven, door-sized hole opened before her as a section of the wall lifted back, then up. After a final thud that made the whole bridge quake, all was silent again except for the gurgle of the stream and the patter of rain.
    Stepping into the gloomy interior, she took a small key-ring flashlight from her coat pocket and switched it on. The dim circle of light revealed she was in a chamber some fifty feet square, with a ceiling that was sufficiently high to allow her to stand upright. She glanced around, registering the dust motes as they drifted lazily through the air, and the cobwebs, as thick as rotted tapestries, which festooned the tops of the walls.
    It had been built by Sarah's great-great-grandfather in the year before he'd taken his family underground for a new life in the Colony. A master stonemason by trade, he'd drawn on all his skills to conceal the chamber within the crumbling and dilapidated bridge, intentionally choosing a site miles from anywhere on the seldom-used farm track. And as to why exactly he'd gone to all this trouble, neither of Sarah's parents had been able to provide any answers. But whatever its original purpose, this was one of the very few places she felt truly safe. Nobody, she believed, would ever find her here. She pulled off her scarf and shook her hair free.
    Her feet on the grit-covered floor broke the tomblike silence as she moved to a narrow stone shelf on the wall opposite the entrance. At either end of the shelf were two rusty, vertical iron prongs, with sheaths of thick hide covering their tips.
    "Let there be light," she said softly. She reached out and simultaneously tugged off both the sheaths to expose a pair of luminescent orbs, which were held in place on top of each prong by flaking red iron claws.
    From these glass spheres no larger than nectarines, an eerie green light burst forth with such intensity that Sarah was forced to shield her eyes. It was as if their energy had been building and building under the leather covers and they now reveled in their newfound freedom. She brushed one of the spheres with her fingertips, feeling its ice-cold surface and shuddering slightly, as if its touch conferred some sort of connection with the hidden city where such orbs were commonplace.
    The pain and suffering she had endured under this very light.
    She dropped her hand to the top of the shelf, sifting through the thick layer of silt covering it.
    Just as she'd hoped, her hand closed on a small polyethylene