《太平广记·卷十六·神仙十六》
临走时，他登上烧毁的房基，看见那炼丹炉已坏了，当中有个铁柱子，有手臂那么粗，好几尺长，那仙师正脱了衣服，用刀子削那铁柱子。
子春强登基观焉，其炉已坏，中有铁柱，大如臂，长数尺，道士脱衣，以刀子削之。
As he was leaving, he looked back at the foundations of the burnt house and saw that the furnace for refining the pill of immortality that had been destroyed. The remains of it were an iron pillar, as thick as an arm and several feet long. The immortal teacher was stripping off his clothes and using a knife to cut the iron pillar.