At the beginning of the next morning shift, on day 1122, the agreed equipment-test signal from Three Steps reached First Vent in six pulses. The answer reached Three Steps in five. Heda separately confirmed that no new flood had begun while they checked the discrepancy.
Heda sent the discrepancy back before Brin had finished copying the first message. Leth checked the indicator at the junction and found that the sixth pulse had passed through the local relay. Somewhere beyond it, the return line had lost a beat.
“Could be a loose contact,” he said.
“Could be someone changing the signal,” Brin replied.
“Could be both,” Iven said.
Brin gave him a look. “You spend a lot of time avoiding the interesting answer.”
“I spend a lot of time making sure it’s the right one.”
The lost pulse mattered because the temporary code Heda and Brin had agreed upon used six strokes for a water warning and five for a request to test the line. A message that arrived shortened could make an urgent problem look like a routine exercise.
