Tunnels 03, Freefall

on his sweat covered face as he stood below one of them. And considering that the massive door must have been airtight, the atmosphere didn't seem to be in the least bit stale to him.
    "Lino," Dr. Burrows said as he took a few steps on the grey and rather shiny floor. "And look... there's hardly any dust in the place at all." He had gone a little way down the passage when he stopped, then glanced over his shoulder at his son. "If you think about it, we're now moving beyond the edge of the cavern wall itself." He turned and held up his hands, his palms outwards, to indicate where he thought the wall should be. "So, while the cavern outside may be a natural feature, I'd say that this passage has been hollowed into the bedrock itself."
    "Yeah," Will said, "but I wonder what's in these." Down one side of the passage were a series of small cabins with metal doors. Dr. Burrows and Will explored the first one of these. The walls were painted with a dark grey gloss up to waist height, above which the remainder of the walls and the ceiling were a rather dirty ivory color, but the cabin was completely empty.
    They backed out of it and into the side passage again.
    " Radio Operator ," Will said, reading the stenciled letters on the door of the next cabin along. As they opened it, they discovered there was a chart on the back of the door, with several months mapped out in a grid and names allotted to specific hours within each day. Neither Will nor his father made any comment as they entered the room itself. It was approximately twice the size of the first cabin, with a bench against the longest wall which was covered with all manner of electronic equipment. Dark grey metal boxes with numerous dials trailed wires down below the bench where they were bound together into a thick snake which fed into a duct in the floor.
    "What are those?" Will asked, pointing at the intricate glass bulbs that protruded from tops of some of the boxes.
    "Radio valves. It's pre-transistor technology," Dr. Burrows said. "And to complete the picture, here's a microphone," he added, pushing aside one of a pair of metal-framed canvas chairs so he could pick up the chunky black object at the front of the bench. He weighed it in his hand, then reached for a pair of headphones that lay beside it. Will opened a loose-leaf file on the bench and flicked through the laminated pages, upon which were matrices of numbers and letters. "Maybe they're codes?" Dr. Burrows suggested.
    But Will was more interested in an old television monitor mounted on the wall to their left. He tried the various switches on it, but nothing happened. "What does that mean?" Will asked as he saw the word ROTOR printed on a map beside the screen. The map was an outline of the British Isles over which scores of overlapping circles had been prescribed.
    Dr. Burrows shrugged. "Doesn't ring a bell with me. Maybe it's an acronym?"
    "No... I bet you the letters stand for something," Will suggested, missing the fleeting smile on his father's face. "Telephones!" Will exclaimed as he noticed the red and black telephones mounted on the opposite wall, next to an old switchboard with a tangle of leads dangling from it. "Should we try to ring someone?" he proposed.
    "Don't waste your time -- I doubt they've worked in years," Dr. Burrows said. "Come along," he laughed, waving Will out of the room.
    The next cabin had the same dimensions, but was an Aladdin's cave of military equipment.
    "An armory!" Dr. Burrows said as soon as he stepped inside. All the wall space was taken up with rough wooden racking. He bent to peer at a stubby-looking weapon on the rack closest to him. It was obscured by thick gobs of dirty-looking grease, but this didn't seem to present any difficulty to Dr. Burrows. "It's a Sten gun," he decreed as he took it from the rack. "A submachine gun first issued to British troops in the forties. They were made in Enfield and were known as the Plumber's Nightmare . You can see why. Ugly-looking thing, isn't it?"
    "Yeah, really ugly," Will said, but his voice was full of wonder.
    The rest of the room was crammed with military equipment, either neatly slotted into the racks or in metal crates piled high in towers against the walls. Each crate was stenciled with numbers and letters, and occasionally with the name of what was inside them.
    Will busied himself by throwing open the lids to some of the crates. The first revealed more guns, entwined with heavily greased sacking, side by side with