The drill was making the wall flinch.
Iven heard the machine first, a regular metal chatter from the service recess beyond the clinical turn. Then the sound changed under his feet. A low movement passed through the older structure, stopped and passed again in the same place.
He put down the drawing case.
At the recess, four men were feeding a narrow boring head through an opening in the human housing. The frame stood square on its rails. Its power connection was guarded. The advance lever had a clean depth mark beside it. None of that made the surface behind the plate dead.
The drill tip entered the pale material beneath.
It tightened away from the cut.
“Stop,” Iven said.
The foreman turned. He was a thick-necked man with a shaved patch above one ear and a pencil pushed into the seam of his cap. A field guard stood beside the control frame, carrying a short baton. Both recognized Iven.
