The stillness in the vault was heavier than stone. Without the slow drift of air through the ceiling chimney pipes, the heat began to climb, warmed by the heat of their bodies and the tiny yellow bead of the trimmed dark-lantern. But it wasn’t a comfortable warmth. It was a damp, clammy heat that smelled of sixty years of decomposing bookbinder’s glue, rancid sheep fat. The acrid, biting stench of sulfur burning acid that seeped from the decomposing dark oak-ink on thousands of discarded parchment quires.
Tomas sat down upon a dry oak packing crate, resting his elbows upon his knees. He had learned the discipline of oxygen conservation during his early winters in the low wash-cellars of Bellwether, where winter ice often choked the chimney pipe pipes and filled the laundry rooms with charcoal fumes. A panicked man breathes thirty times a minute, gulping down air and filling his blood with terror. A working cart driver, accustomed to pacing his breath against ninety-pound loads, slows his pulse by conscious will. It drew steady, shallow breaths through his nose and held each breath out for four deliberate heartbeats.
“Keep your heads low,” Tomas instructed softly, his voice scarcely above a whisper. “Carbonic acid gas is heavier than sky air. In a fully stale room, it will eventually pool in the drainage gutter. But the heat from our bodies will cause the stale air to rise and swirl. Don’t make any sudden movements. Every unnecessary motion burns coal in your lungs.”
