The sphincter-valve at the apex of the lower channel was four meters across. It was built from six overlapping plates of hardened bone that interlocked like the iris of a clockwork camera.
Arthur Vance didn’t use explosives or star-fire torches to breach it. Instead, he knelt before the valve’s outer rim. He used his razor-sharp razor knife to make a precise three-inch clean cut into a pale, pulsating nerve knot cluster embedded in the surrounding joint padding. He injected five cubic inches of dilute zinc sulfate solution directly into the nerve node. The chemical shock bypassed the creature’s central nervous control. That forced the muscular sphincter to undergo a reflex parasympathetic burst.
With a wet, high-pressure sigh, the bone iris dilated wide, venting a cloud of freezing, amber-tinted mist that tasted of dry aether and stone-hard fossil dust.
Arthur stepped through the sky-slit, Grimm flanking his left hip in a tight heel-walk, his black ears swiveling to track the whistling draft. Pip remained perched on Arthur’s right shoulder plate, his head tilting with rhythmic, curious twitches. Meanwhile, Vesper drifted behind them like an unmoored shadow, her starlit whiskers shimmering in the freezing gloom.
Beyond the valve lay a cavernous hollow so huge that Arthur’s shoulder lamp failed to light up the opposing wall.
