Although they have strong associations with doom, some legends paint fairy circles as places of fertility and fortune. Welsh folk belief is that mountain sheep that eat the grass of a fairy ring flourish, and that crops sown from such a place will prove more bountiful than those from normal land. A folk belief recorded in the "Athenian Oracle" claims that a house built on a fairy circle will bring prosperity to its inhabitants. Likewise, a legend from Pont y Wern says that in the 13th or 14th century, the inhabitants of the town of Corwrion watched fairies dancing in a ring around a glow worm every Sunday after church at a place called Pen y Bonc. They even joined the sprites in their revels. The legend survives in a rhyme: "With the fairies nimbly dancing round / The glow-worm on the Rising Ground." John Rhys recorded a Welsh tale in 1901 that tells of a man who supposedly lived on the side of the Berwyn, above Cwm Pennant, in the early 19th century. The man destroyed a nest of rooks in a tree surrounded by a fairy ring. In gratitude, the fairies gave him a half crown every day but stopped when he told his friend, "for he had broken the rule of the fair folks by making their liberality known". Nevertheless, fairy boons are not without their curses, and tales often tell of the sprites exacting their revenge.