Tunnels 03, Freefall

blinking myopically at his son.
    "You mean these?" Will asked, wondering what was so vitally important about the bundle as he took it from his pocket and passed it to his father.
    Dr. Burrows fumbled it open and, one by one, felt the flat pieces of stone. "Thank God, they're all right. None of them are broken or lost. Well done, Will. Really well done!"
    "Good, no problem, Dad," Will said, still at a loss to know why his father was showing more concern for some little pieces of stone than he was for anything else. More even than for Will.
    "Now where are my glasses?" Dr. Burrows said, and immediately began to crawl on all fours to locate them.
    "But, Dad, I can' t believe this!" Will gushed, as the realization sank home that against all odds they had been reunited. "We're back together again! It's so brilliant to see you when--"
    "Yes, but I can't see anything!" Dr. Burrows snapped at him in a bad-tempered way, still looking for his glasses.
    Will hovered by his father for a moment, torn between staying with him or finding out if Chester and the others had escaped the explosion. "Dad, I'll be back in a minute. I'll help you find them then," he told his father, not waiting for a response as he whisked around and began down the tunnel.
    Although it wasn't very far to the entrance, the pieces of fungus made the going tricky. Due to the slick of oily fluid in the bottom of the tunnel, the larger slabs of fungus slid from under him as he climbed on top of them. And at one point the tunnel was completely obstructed and he was forced to clear away the debris before he could proceed. As he hefted sizeable chunks of fungus aside, he realized that it had probably saved their lives -- not only had it absorbed the blast, but it had also cushioned their landings.
    As he finally reached the mouth of the tunnel, he was met by the strangest calm. He was just about to step out when he happened to glance down. He gasped, stopping himself in the nick of time. There was nothing before him but a huge gaping hole. The entire floor of the cavern had completely disappeared. Although he couldn't see the bottom, the cavern walls were illuminated by the small fires that still burnt on them, like candles in the niches of a church grotto.
    Dr. Burrows appeared beside his son, having retrieved his glasses. For a while they simply stared into the cavern, watching as rocks and pieces of fungus detached from the roof and dropped into the blackness. Then they heard a low grinding sound.
    "The submarine," Will whispered, seeing it judder, then settle down again.
    "Submarine?" his father asked, as if he hadn't appreciated what was there before.
    It was quite something to behold; first burnt all over the vessel and the fungus coating had been blasted away, so its streamlined hull was clearly visible. But something seemed to be happening to it.
    There was a tremendous cracking sound that made both Will and his father flinch, then more grinding sounds. The submarine shook and dropped a small distance, then, as they watched, it seemed to be toppling sideways, but in slow motion.
    "It's going! It's falling!" Will exclaimed. The explosion had evidently destroyed either the fungus or the bedrock on which the hull had been lodged -- or both -- and now there was nothing to prevent it continuing on its way down.
    With a last tremendous groan, it tipped over, completely vanishing from view and leaving just the blackness of the void. Will and his father heard distant crashing sounds as it collided with the sides as it went.
    "I wonder if the Rebecca twins were on it," Will said quietly. "They had it coming."
    "Dr. Burrows fixed his eyes on his son. "You're going to have some explaining to do, my boy," he declared solemnly.
    "Huh?"
    "I just hope you know what you've done," Dr. Burrows said, his voice grave as he waved his hand in the direction of the crater. He shook his head, his unevenly-cut hair, soused in fungus juice, sticking up in spikes as if he was some middle-aged punk. He looked quite ridiculous.
    "You what?" Will spluttered. "I don't know quite how we managed it, but we just got out of there alive ... and you're acting like some bloody school teacher. You have got to be joking!"
    "Of course I'm not joking," Dr. Burrows retorted sharply. "You're going to be in big trouble for your part in this."
    That was it for Will -- he began to snort, then burst into a full-bodied laugh. "Big trouble," he repeated, his voice squeaking with incredulity. Catching his