Ruo sent the courier message to engineer Qiao at the border station using the address Bai had copied from the archive letter. She wrote the question on the official form: did he still have the site measurements for Gu’s local-regulator plan, and could he provide verified copies?
Bai checked the wording before she sealed it. “Ask him to preserve the originals where they are. We need copies, not a second lost archive.”
Ruo nodded and sent the message through the capital route. “Four days if the north road stays open.”
Yan looked toward the study room window. “I could carry the request faster.”
“Your body could,” Gu said. “But the courier’s official route has a stamped receipt. Qiao can answer it without someone arriving at his door carrying a half-remembered request.”
Yan’s eyes narrowed. He knew Gu was right, which did not make the waiting easier. “Fine. We wait for the reply.”
Gu unfolded the copied plans and compared Qiao’s old notes with the archive sketch. The local regulators could fit the border furnace without replacing its central feed. The design could support a controlled trial, but its safety depended on the current machine’s condition.
Qinghe read the clinic reports attached to the project file. “We also need current medical data from workers who used the old formula. The plans alone can’t tell us whether changing the flow reduces harm.”
