Ida kept the lamp low as she unlocked the chart room. Salt had silvered the lock, but the key still turned. Her father’s tide charts lay in careful stacks. She took the newest one first.
The same reef appeared twice, one cable apart. Ida checked the older charts. They showed it once.
A chain rattled outside. Marta stood at the boathouse doors with the harbour key in her fist. She did not ask what Ida had found. Her eyes went straight to the doubled reef. “No one takes a boat tonight,” she said.