Tunnels 01, Tunnels

directions.
    "I don't get this 'As below, so above' stuff," Will told Cal in a low voice. "I thought everybody hated Topsoilers."
    "Above isn't Topsoil ," Cal replied, so loudly and in such a petulant tone that several burly men in earshot turned to regard Will with snarls of disgust. He winced -- he was beginning to wonder if having a younger brother was all it was cut out to be.
    "But how often do you have to do that -- go to church?" Will ventured when he had recovered sufficiently from Cal's last response.
    "Once a day," Cal said. "You go to church Topsoil, too, don't you?"
    "Our family didn't."
    "How strange," Cal said, looking shiftily around to check that no one could overhear him. "Load of drivel, anyway," he sneered under his breath. "C'mon, we're going to see Tam. He'll be at the tavern in Low Holborn."
    As they reached the end of the street and turned off it, a flock of white starlings spiraled above them and swung into a barrel roll toward the area of the cavern where the boys were now heading. Appearing from nowhere, Barleby joined them, flicking his tail and wobbling his bottom jaw at the sight of the birds, and giving a rather sweet and plaintive mew that was totally at odds with his appearance.
    "Come on, you crazy beast, you'll never catch them," Cal said as the animal sauntered past, his head held high as he hankered after the birds.
    As the boys walked, they passed hovels and small workshops: a smithy where the blacksmith, an old man, backlit by the blaze from his furnace, hammered relentlessly on an anvil, and places with names like Geo. Blueskin Cartwrights and Erasmus Chemicals. Of particular fascination to Will was a dark, oily-looking yard full of carriages and broken machinery.
    "Shouldn't we really be getting back?" Will asked, stopping to peer through the wrought-iron railings at the strange contraptions.
    "No, Father won't be home for a while yet," Cal said. "Hurry up, we should get a move on."
    As they progressed toward what Will assumed was the center of the cavern, he couldn't stop himself from looking all around at the amazing sights and the packed houses, huddled together in seemingly endless rows. Until now he hadn't fully appreciated just how huge this place was. And looking up he saw a shimmering haze, a shifting, living thing that hung like a cloud above the chaos of rooftops, fed by the collective glow of the light of all the orbs below.
    For a moment, it reminded Will of Highfield during the summer doldrums, except that where there should have been sky and sunlight, there were only glimpses of an immense stone canopy. Cal quickened his pace as they passed Colonists who, from their lingering glances, evidently knew who Will was. A number crossed the road to avoid him, muttering under their breath, and others stopped where they stood, glowering at him. A few even spat in his direction.
    Will was more than a little distressed by this.
    "Why are they doing that?" he asked quietly, falling back behind his brother.
    "Ignore them," Cal replied confidently.
    "It's like they hate me or something."
    "It's always the same with outsiders."
    "But...," Will began.
    "Look, really, don't worry about it. It'll pass, you'll see. It's because you're new and, don't forget, they all know who your mother is," Cal said. "They won't do anything to you." All of a sudden, he drew to a halt and turned to Will. "But through here keep your head down and keep moving. Understand? Don't stop for anything ."
    Will didn't know what Cal was talking about until he saw the entrance by the other boy's side: It was a passage barely more than shoulder-width. Cal slipped in, with Will reluctantly following behind. It was dark and claustrophobic, and the sulfurous stench of old sewage hung in the air. Their feet splashed through unseen puddles of unidentifiable liquids. He was careful not to touch the walls, which were running with a dark, greasy slime.
    Will was grateful they finally emerged into the dim light, but then he gasped as he beheld a scene that was straight out of Victorian London. Buildings loomed on either side of the narrow alleyway, slanting inward at such precarious angles that their upper stories almost met. They were timber-framed and in a terrible state of disrepair. Most of their windows were either broken or boarded up.
    Although he couldn't tell where they originated, Will heard the sound of voices and cries and laughter coming from all around. There were odd snatches of music, as if scales were