“Back off the toggle reader,” Myrian Vitremarvis bellowed through his bullhorn. “Unclutch the address drive from the operatin’ counter.”

A series of metallic bangs punctuated by less-metallic blasphemies from the floor above accompanied the execution of this order.

“Okay, now get the donkey strapped up. Advance address counter to 12,732. 12,732, you hear?” He turned to belabor the crew behind him. “Now lower away on the bit winch. Get the shackle down to the reader level –”

A clangor cut him off, as the operating-code shaft spun and the great master toggle chain clattered down into the depth of its well.

“Okay, 12,732? Give me the next eight toggles in sequence.”

“Up, up, down, down, up, up, up, down, boss,” a yell came down from the reader balcony, “and the edging lines are right.”

“Clamp it and cut it. Cut it above, remember, we’re losing link 12,731.” He turned again. “Lower away on the bit winch, get us space. First chain!” A gesture with a wrench ushered in a half-dozen junior operators bearing another length of toggle chain on their shoulders. “Give me the leader.”

Myrian scrutinized the pattern of lines etched into the first link of the new chain. “It’s valid. Get it up to the reader walk.” He raised his bullhorn again. “Got it? Weld it. Then run the address counter forward until the loose end’s up at the reader walk. And haul away on the bit winch, get the shackle back at par – then hook that and weld it, too.”

A flurry of acknowledgements came back.

“Good. Now run the chain back seven hundred sixty-eight places, an’ get the reader in position. Rig for a test read-and-compare off the donkey. Seventeen more chains to patch and only a day and a half left in the maintenance window – so snap it up, you code dogs!”