The summons came before the disposal carts left the yard.
Attendant Wu waited at the gate with a paper in his hand. Yan had just tied down the last empty jar crate. His palms smelled of ash and old rope.
“Elder Zhao wants you in the testing room,” Wu said. “Now.”
“What for?”
“A witness to a batch test.”
“Whose batch?”
Wu glanced at the paper. “The elder’s.”
Yan looked past him toward Furnace Three. The first cart was already moving toward the slope. “Can this wait until the shift bell?”
“It cannot.”
Wu held out the summons. The wording was brief: report to the experimental corridor, confirm receipt, attend testing. There was no description of the medicine or the kind of witness expected. Yan signed the receipt line, keeping his handwriting small.
Ren came up with the next cart. “You leaving the count?”
“Only for a test.”
Ren looked at Wu. “Is he allowed to refuse?”
Wu’s mouth went tight. “The contract assigns him to the elder’s work.”
Yan thought of the open ledger and Ning’s name beside his. “I’ll come.”
The clean corridor felt cold after the yard. Wu led him past shelves of sealed jars to a testing room with one table, two chairs, and a wash basin. A covered cup sat at the center. A contract ledger lay open near it. Both siblings’ names appeared beside the same labor clause.
Elder Zhao Heng stood by the window. He wore a dark robe with a narrow gold edge, and his hair was tied back without a loose strand. He had the steady manner of a man accustomed to being obeyed without raising his voice.
“Shen Yan,” he said. “Sit.”
Yan did not sit yet. “The summons says I’m a witness. What am I witnessing?”
“A human test of a new cultivation draught.” Zhao gestured toward the cup. “The animal trials produced strong qi accumulation. We need to confirm the result in a human body.”
“Has a volunteer agreed?”
“The sect assigned the test as part of your work.”
Yan glanced down at the ledger. His own name was beside a line about refusal. Ning’s was below it. “So no one has agreed.”
Zhao’s eyes remained on him. “A labor assignment is not a question of agreement. Your contract gives Ashfall authority to extend your service if you refuse a necessary duty.”
The elder did not threaten to hurt Ning. He did not have to. The open page said enough. Yan had spent years learning how much a clerk could do with one line in a ledger. He could refuse and hope the elders ignored the terms, or drink the draught and find out what Zhao wanted.
He pulled out the chair and sat. “Tell me what’s in it.”
Zhao uncovered the cup. The liquid was dark and clear, with a pale ring of oil around the edge. Yan smelled bitter root and the mineral tang of black salt.
“Frostvine, river ginseng, and black salt,” Zhao said. “The frostvine tempers the ginseng’s heat. The black salt carries the qi into the channels. In animal trials, the draught accumulated qi quickly.”
“And the risk?”
“Meridian corrosion. It can be severe in a novice, but the body usually recovers.”
“Usually?”
“The amount is controlled. The benefit is worth the risk.” Zhao tapped the batch card. “No meaningful contaminant was found.”
“If the pain starts, what should I do?”
“Sit still and let Wu measure you.”
“If I can’t sit still?”
“Then Wu will keep you from falling.” Zhao said it as if the possibility were an inconvenience, not a reason to stop. “The sample is small.”
Yan looked at the cup. It was ordinary ceramic, white with a blue rim. A brown ring marked the inside where the liquid had dried before it was poured. “You’ve tested it on animals. Has anyone taken this same dose before?”
“Not in a human trial.”
“Then how do you know the amount is controlled?”
“We measured it against the animal result and reduced the dose.”
Yan turned the batch card so he could read the ingredients himself. The script was clear, though the numbers beside the black salt were cramped. “Does the salt cause the corrosion?”
“It carries the qi. The frostvine should protect the channels.”
“Should?”
Zhao’s gaze sharpened. “The recipe is sound. If you want to debate every word, we will not finish before the bell.”
“I want to know what to expect.”
Wu set down a small hourglass beside the tray. “We’ll watch the pulse for the length of this measure. If you become faint, tell me. If you feel pain, tell me where it moves.”
Yan checked the sand. “And if the pulse gets worse?”
“We’ll treat you,” Wu said.
Zhao added, “The test is not designed to harm you.”
It did not answer what would happen if it did. Yan looked at the ledger again. There was a place for the dose, a place for his pulse, a place for the result. No line asked whether he wanted to be there.
Yan looked at the card. The ingredient lines were written in neat black ink. The space beside “impurity” was blank.
“What was in the sample before it was mixed?”
“Nothing that affected the recipe.”
“That isn’t the same as nothing.”
Zhao’s expression did not change. “The assistants found no meaningful contaminant. We are testing the draught, not the jar.”
Attendant Wu set a measuring tray beside the cup. The scale was clean; the weights had been wiped. “Please sit still for the baseline,” he said.
Yan held out his wrist. Wu counted the pulse, then wrote it on the slip. Yan asked him to record the time and dose too.
“You want a complete record?” Wu asked.
“A test needs a before and an after.”
Zhao considered him, then nodded. “Record it.”
Wu wrote the starting pulse, the cup’s batch number, and the measured quantity. Yan watched each word form. He had seen workers lose pay because someone forgot to write a day. He did not intend to let this test become an unnamed thing that happened without a record.
“Any allergies?” Wu asked.
“Refinery dust irritates my lungs. I take an ordinary broth for it.”
“Anything else?”
“No.”
“Recent injury?”
“My hand is cut from the yard. Nothing serious.”
Wu made a note. Zhao pushed the cup toward Yan.
Yan looked once at the door. He could walk out, but the contract would remain open on the table. He thought of Ning’s bill and the shift she wanted to change. He thought of the way she had asked the physician questions herself. She had not asked him to make this choice for her; the choice belonged to him.
“Will the test affect her treatment schedule?” he asked.
“The experiment is separate from the infirmary,” Zhao said. “Your sister’s bill is unchanged.”
It was not an answer about what refusal would mean. Yan had asked anyway.
He reached for the cup. The liquid warmed his fingers through the ceramic. He could smell the bitter root more clearly now. He raised it, felt the rim touch his lip, and drank.
The draught was bitter enough to make his tongue curl. He swallowed once, then again, until the cup was empty. He set it back on the tray and waited for Zhao to tell him what came next.