Tunnels 03, Freefall

that a pier -- also constructed of concrete and approximately fifteen meters long -- branched off it and out into the lagoon. Down both sides, this pier had rusted iron bollards set into its surface, several of which had chains hanging from them, although it wasn't obvious what these were for as they trailed into the water. Will ran to the side to see them more clearly.
    'Dad, what are those down there? Boats?" he asked, spying several vessels -- basic looking dinghies -- attached to the chains but lying on the bottom of the lagoon. They were either made of plastic or fiberglass, and all in varying stages of disintegration. Others were completely broken up, and now the cavern was so well lit Will could see their remains scattering the far bank amongst the craggy rocks.
    "They certainly are. And see over there, Will!" Dr. Burrows shouted. "It's a barge!"
    As he peered into the far corner of the cavern, Will spotted a long vessel in the water, its sides mottled with a patina of rust. It appeared to have broken free from its mooring and drifted to its current position, its bow touching the cavern wall. At the helm there was a small cabin, and the rest of the vessel was open, with metal crates stacked in it.
    "Good God, Will, this is some kind of underground harbor!" Dr. Burrows said, his words clipped by his sheer excitement. He immediately began to survey what was on the rest of the quay, which continued for several hundred meters from where they were standing. As he and Will spotted more buildings along the base of the cavern wall, they broke into a run to reach the nearest of them. The first had a door with another rotating handle in the center, and Dr. Burrows wasted no time in tackling it.
    "Want me to have a go?" Will offered as his father struggled with it.
    "No, leave it to me," Dr. Burrows replied as he spat on his palms and resumed his efforts. He strained hard and the handle finally began to move, then he pulled the door open. There was a hiss as air was released from inside.
    "Oh, yeuch!" Will gasped, wrinkling his nose as they both ventured in. "Dad, that wasn't you, was it?"
    "Most certainly not!" Dr. Burrows huffed indignantly. "Smells a little like swamp gas... like methane. There must have been a build up of it in here."
    "Sorry," his son mumbled, throwing himself into an examination of the interior to mask his embarrassment. With its meter-thick walls, the concrete cabin had the same internal dimensions as the first building, but was windowless. The lights didn't seem to be working, so Will used his lantern to explore it. Three sizeable engines were mounted in pits sunk into the floor, rainbow-crazed pools of fluid around their bases.
    "Generators?" Dr. Burrows said. "Yes. See the fuel lines going into them, and the electrical conduits and switching gear on the wall over there?"
    "Er... I think I've found what smells so bad," Will announced from a corner of the cabin. His lantern revealed a Thermos flask with a faded tartan pattern on it, and, beside it, an open-topped plastic box, inside which there was something black with rot.
    "Somebody forgot their lunch," Dr. Burrows grinned.
    "It's a bit more than that, Dad," Will said as he peered into the box. "There's a rat in here, too... and it's been dead for a very long time."
    "Probably got locked in and that's all it had to eat," Dr. Burrows suggested as they left the cabin to try the next building along.
    In this one they found that the walls were lined with sturdy metal shelves, on which were a number of wooden crates. Dr. Burrows heaved at one of these. Not realizing just how heavy it was, he found he couldn't support it as he slid it off the shelf. "Damn!" he yelled, jumping back, as it crashed to the floor and broke open. Assisted by Will, he lifted the pieces of crate aside. They could see there was something large, wrapped in oil-stained cloth, which ripped as they tugged at it.
    "What is it?" Will asked.
    "An outboard motor, I think," Dr. Burrows said, as he slid a finger over the marine screw. With the grease removed, the metal shone brightly. "Yes. And in bloody good nick too!" He turned to his son, and grinned. "This is all incredible. Let's see what else is here," he said, and they both returned outside.
    Moving down the quayside, they reached the next building but Dr. Burrows didn't stop, jogging past it and several others along the way. He seemed to be in a tearing hurry as if he'd spotted something just beyond them. There were two