"There isn't any water around here, is there?" Chester asked quickly.

"Just this." Will reached into a cardboard box on the table and handed his friend a plastic bottle of water. "Let's just chill out for a while."

They both sat in the old armchairs, sipping from the bottles, while Chester looked up at the roof and craned his neck to look at the two branch tunnels.

"It's so peaceful, isn't it?" Will sighed.

"Yes," Chester replied. "Very… um… quiet."

"It's more than that, it's so warm and calm down here. And the smell… sort of comforting, isn't it? Dad says it's where we all came from, a long time ago — cavemen and all that — and of course it's where we all end up eventually — underground, I mean. So it feels sort of natural to us, a home away from home."

"Suppose so," Chester agreed dubiously.

"You know, I used to think that when you bought a house, you owned everything under it as well."

"What do you mean?"

"Well, your house is built on a plot of land, right?" Will said, thumping his boot on the floor of the cavern for effect. "And anything below that plot, going right down to the earth's core, is yours as well. Of course, as you get nearer the center of the planet, the 'segment, if you want to call it that, get smaller and smaller, until you hit the very center."

Chester nodded slowly, at a loss for what to say.

"So I've always imagined digging down — down into your slice of world and all those thousands of miles that are going to waste, instead of just sitting in a building perched on the very crust of the earth," Will said dreamily.

"I see," Chester said, catching on to the idea. "So if you were to dig down, you could have, like, a skyscraper, but facing the wrong way. Like an ingrown hair or something." He involuntarily scratched the eczema on his forearm.

"Yes, that's exactly right. Hadn't thought of it like that. Good way of putting it. But Dad says you don't actually own all the ground under you — the government has the right to build subway lines and things if they want to."

"Oh," Chester said, wondering why they had been talking about it in the first place, if that was the case.

Will jumped up. "OK, grab yourself a pickax, four buckets, and a wheelbarrow, and follow me down here." He pointed to one of the dark tunnels. "There's a bit of a rock problem."

Meanwhile, back up at ground level, Dr. Burrows strode purposefully along as he made his way home. He always enjoyed the chance to think while he walked the mile and a half or so, and it meant he could save on the bus fare.

He stopped outside the newsstand, abruptly halting in midpace, teetered slightly, rotated ninety degrees, and entered.

"Dr. Burrows! I was beginning to think we'd never see you again," the man behind the counter said as he looked up from a newspaper spread out before him. "Thought you might've gone off on a round-the-world cruise or something."

"Ah, no, alas," Dr. Burrows replied, trying to keep his eyes off the Snickers, Milky Ways, and Mars bars that were displayed enticingly in front of him.

"We've kept your backlog safe," the shopkeeper said as he bent below the counter and produced a stack of magazines. "Here they are. Excavation Today, The Archaeological Journal, and Curator's Monthly. All present and correct, I hope?"

"Tickety-boo," Dr. Burrows said, hunting for his wallet. "Wouldn't want you to let them go to anyone else!"

The shopkeeper raised his eyebrows. "Believe me, there isn't exactly an excessive demand for these titles around here," he said as he took a Ј20 note from Dr. Burrows. "Looks like you've been working on something," the shopkeeper said, spotting Dr. Burrows's grimy fingernails. "Been down a coal mine?"

"No," Dr. Burrows replied, contemplating the dirt encrusted underneath his nails. "I've actually been doing some home repairs in my cellar. Good thing I don't bite them, isn't it?"

Dr. Burrows left the shop with his new reading matter, trying to tuck it securely into the side pocket of his briefcase as he pushed open the door. Still grappling with the magazines, he backed blindly out onto the sidewalk, straight into somebody moving at great speed. Gasping as he rebounded off the short but very heavyset man he'd blundered into, Dr. Burrows dropped his briefcase and magazines. The man, who had felt as solid as a locomotive, seemed totally unaffected and merely continued on his way. Dr. Burrows, stuttering and flustered, tied to call after him to apologize, but the man strode on purposefully, readjusting his sunglasses and turning his head slightly to give Dr. Burrows an unfriendly sneer.

Dr. Burrows was flabbergasted. It was a man-in-a-hat. Of late, he had begun to notice, among the general population of Highfield, a type of person that seemed — well, different, but without sticking out too much. Being a habitual people watcher, and having analyzed the situation as he always did, he assumed that these people had to be related to one another in some way. What surprised him most was that when he raised the subject nobody else in the Highfield area seemed to have registered at all the rather peculiarly slope-faced men wearing flat caps, black coats, and very thick dark glasses.

As Dr. Burrows had barged into the man, slightly dislodging his jet-black glasses, he'd had a chance to see a «specimen» at close hand for the very first time. Apart from his oddly sloping face and wispy hair, he had very light blue, almost white, eyes against a pasty, translucent skin. But there was something else: A peculiar smell hung around the man, a mustiness. It reminded Dr. Burrows of the old suitcases of mildewed clothes that were occasionally dumped on the museum steps by anonymous benefactors.

He watched the man stride purposefully down Main Street and into the distance, until he was only just in view. Then a passerby crossed the road, interrupting Dr. Burrows's line of sight. In that instant, the man-in-a-hat was gone. Dr. Burrows squinted through his spectacles as he continued to look for him, but although the sidewalks were not that busy, he couldn't locate him again, try as he might.

It occurred to Dr. Burrows that he should have made the effort to follow the man-in-a-hat to see where he was going. But, mild-mannered as he was, Dr. Burrows disliked any form of confrontation and quickly reasoned with himself that this was not a good idea given the man's hostile manner. So any thought of detective work was quickly abandoned. Besides, he could find out on another day where the man, and perhaps the whole family of hated look-alikes, lived. When he was feeling a little more intrepid.

Underground, Will and Chester took turns at the rock face, which Will had identified as a type of sandstone. He was glad that he'd recruited Chester to help with the excavation, since he really seemed to have a knack for the work. He watched with quiet admiration as Chester swung the pickax with immense force and, once a fissure opened up in the face, seemed to know exactly when to pry out the loose material, which Will quickly shoveled into buckets.

"Need a break?" he suggested, seeing that Chester was beginning to tire. "Let's take a breather." Will meant this literally, because with the entrance to the dig covered up, it all too soon became very airless and stuffy where they were, twenty feet or so from the main chamber.

"If I take this tunnel much father," he said to Chester as they both pushed loaded wheelbarrows before them, "I'll have to sink a vertical shaft for ventilation. It's just that it's such a drag putting one of those in, when I could be making more headway down here."

They reached the main chamber and sat in the armchairs, drinking the water appreciatively.