Smoke on the Hill — Daily puzzle for 2026-10-23

Medium — logic-grid deduction puzzle

Five charcoal burners each fired one pit on the hillside, and you work out when each one did it, which wood they stacked and which cover they used.

Five charcoal burners climbed the hill before the sun was up: Algernon, Ottoline, Gilbert, Maud and Zachary. Each one piled a different kind of wood into a pit, lit it, and sealed it under a different cover so the fire would burn slow and low. The pits were lit one at a time, from dawn to dusk, so every burner had a turn of their own. By evening the whole hill was smoking, the notes were smudged with soot, and nobody could quite remember who had done what. Read the notes and set it straight.

Clues

1. Ottoline took the turn right after Algernon.
2. Gilbert's pit was lit immediately after Ottoline's.
3. Maud lit a pit later than Gilbert, but still before dusk.
4. The oak stack was Algernon's or Gilbert's, and the alder stack belonged to the other of the two.
5. Ottoline had one of the beech and birch stacks, and Maud had the other.
6. Of Algernon and Gilbert, one tended the oak stack and the other sealed a pit under the slate cover.
7. The oak stack went to one of Algernon and Zachary, and the ash cover to the other.
8. One of Ottoline and Maud tended the beech stack; the other used the turf cover.
9. At least one of these is true: the oak stack burned in the turn just before the beech stack, or the clay cover went on in the turn just before the slate cover.
10. The clay cover went on before the moss cover did.

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