Mirror iron was still the limit.
Every module needed a channel lined with it. The lining was what let the channel carry the well’s flow without the flow eating the metal: the same lining that had made the Hearth heart work, and the ribs, and the collar’s growing. And the crew had almost none left. One whole sheet, at Lorn, under Lisan’s custody. And a box of offcuts from the ribs’ linings, on the findings shelf, none bigger than Mara’s hand.
So the first module’s channel was a short-section version. Instead of one long lining down the channel’s length, it took a series of short pieces, cut from the offcuts, butted end to end inside the channel and pressed into the body.
They tested it at the second hour of the afternoon.
Sen ran a low flow through it from a test line off the reservoir. Not the well’s full flow; a fraction, a trickle, enough to make the channel ring.
Mara stood at the bench with the module in its frame in front of her.
She heard it.
Not well. Not the way she would once have heard it. The coupling was off, on the bench where she had set it in the growth chamber, logged as removed. The graft alone gave her only a faint buzz behind her left ear, at this distance, through the frame and the body and the lining.
