Tunnels 01, Tunnels

said.
    "Could it be a gas pipe?"
    "Nope, doesn't smell like it and, anyway, they've never been made of brick. Judging by the echo, it's quite a large space." His eyes flashed with anticipation. "I just knew we were on to something. Get me a candle and the iron rod from the main chamber, will you?"
    When Chester returned, Will lit the candle a good distance back from the hole and then carried it slowly before him, nearer and nearer to the opening, watching the flame intently with every step he took.
    "What does that do?" Chester asked as he looked on in fascination.
    "If there are any gases you'll notice a difference in the way it burns," Will answered matter-of-factly. "They did this when they cracked open the pyramids." There was no change in the flickering flame as he brought it closer, then held it directly in front of the opening. "Looks like we're all clear," he said as he blew out the flame and reached for the iron rod Chester had leaned against the tunnel wall. He carefully lined up the ten-foot pole with the hole and then rammed it through, pushing it all the way in until only a short length protruded from between the bricks.
    "It hasn't hit anything -- it's pretty big," Will said excitedly, grunting with exertion as he checked the depth by letting the end of the pole swing down. "But I think I can feel what might be the floor. OK, let's widen this a bit more."
    They worked together and within moments had removed enough bricks for Will to slither through headfirst. He landed with a muffled groan.
    "Will, are you all right?" Chester called.
    "Yes. Just a bit of a drop," he replied. "Come in feetfirst, and I'll guide you down."
    Chester made it through after a tremendous struggle, his shoulders being broader that Will's. Once he was in, they both began to look around.
    It was an octagonal chamber, with each of its eight walls arching up to a central point about twenty feet above their heads. At its apex was what appeared to be a carved stone rose. They shone their flashlights in hushed reverence, taking in the Gothic beading set into the perfectly laid brickwork. The floor was also constructed from bricks laid end on end.
    "Awesome!" Chester whispered. "Who'd have ever expected to find anything like this?"
    "It's like the crypt of a church, isn't it?" Will said. "But the strangest thing is..."
    "Yes?" Chester shone his flashlight at Will.
    "It's absolutely bone-dry. And the air's sort of sharp, too. I'm not sure--"
    "Have you seen this, Will?" Chester interrupted, flicking his light around the floor and then over the wall nearest to him. "There's something written on the bricks. All of them!"
    Will immediately swiveled around to study the wall closest to him, reading the elaborate Gothic script carved into the face of every brick. "You're right. They're names: James Hobart, Andrew Kellogg, William Butts, John Cooper..."
    "Simon Jennings, Daniel Lethbridge, Silas Samuels, Abe Winterbotham, Caryll Pickering... there must be thousands in here," Chester said.
    Will pulled his mallet from his belt and began to knock on the walls, taking soundings to see if there was any sign of a hollow or adjoining passage. He had methodically tapped away at two of the eight walls when for no apparent reason he suddenly stopped. He clapped a hand to his forehead and swallowed hard.
    "Do you feel that?" he asked Chester.
    "Yeah, my ears popped," Chester agreed, sticking a gloved finger roughly into one of his ears. "Just like when you take off in a plane."
    They were both silent, as if waiting for something to happen. Then they felt a tremor, an inaudible tone, somewhat akin to a low note played on an organ -- a throbbing was building, seemingly within their skulls.
    "I think we should get out." Chester looked at his friend blankly, swallowing now not because of his ears but because of the waves of nausea welling up inside him.
    For once Will did not disagree. He gulped a quick yes, blinking as spots appeared before his eyes.
    They both clambered back through the gap in double-quick time, then made their way to the armchairs in the main cavern and slumped down in them. Although they had said nothing of it to each other at the time, the inexplicable sensations had ceased almost immediately after they were outside the chamber.
    "What was that in there?" Chester asked, opening his mouth wide to flex his jaw and pressing the palms of his hands against his ears.
    "I don't know," Will replied. "I'll get my dad to come and see it -- he