Sella led Gu into the regulator room, with Han keeping the station master outside. Yan and Qinghe followed at a distance from the brass casing. A faint bell rang each time the furnace drew power.
“That’s the fourth-minute sound,” Yan said.
Qinghe listened, then compared the ring to her notes. “Same rise before the tremor.”
Sella looked at the station engineer. “You hear that and polish the gauge instead of opening the casing?”
The engineer, Pao, held up a key. “It’s sealed by Registry order. The master keeps the duplicate.”
The seal looked newer than the regulator. Gu saw a local command mark stamped over an imperial one. Pao said he had installed neither.
Sella asked Han to open it in front of witnesses. The station master refused from the corridor. Han told him she would record the refusal and gave him one chance to reconsider. He took the key from his belt and passed it over without looking at her.
When the casing came free, dust spilled from the return vent. A thin crack ran through the ceramic lip. The bell had been warning them about pressure, not calling for more power.
