Moth-winged woman with skull and roses

The lamp in the Ossery dome went dark again last night, and by dawn the moths had come down the ventilation shafts in their hundreds, pale and dusted with soot, looking for it the way they always do. Mother Ysolde stood under the cold glass with her palms open and let them settle on her arms until her sleeves were furred with wings. She has kept the wick since before the grid was rewired, and she says the moths were here first and will not be told where the light lives now.

The engineers came up from the lower levels with their clipboards and their talk of cold cells and sealed panels. They said the flame was a fire hazard and a waste of tallow, and that the dome could be lit by a single humming strip that never needed tending. Ysolde heard them out with a red rose tucked behind one ear, the skull she keeps for funerals pinned at her crown, and then she asked them to name one thing the strip could do that a moth could not follow. They had no answer. She laughed, and the moths lifted off her like smoke.

That evening she pressed a cross on a beaded cord into my hand. It is bone, not metal, carved by a man who has been dead longer than the chapel roof. She told me to climb the north shaft with a jar of the last tallow and light it at the top, where the old beacon sits behind the vent grille. I did not want to go. The shaft is black for three hundred metres and the air tastes of rust.

I am writing this from the ledge with the jar between my knees. The flame is small and the wind keeps trying to take it. Below me the moths are rising in a slow pale column, and I think they can see it. If the light holds, you will know from the north wall. If it does not, follow the moths.