It is narrated from Sayyiduna Abu Sa'id al-Khudri (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said concerning (the saying of Allah Almighty) "water like molten brass (al-muhl)" [Surah al-Kahf: 29] : "It will be like the dregs of olive oil; when he (the dweller of Hell) brings it near his mouth, the skin of his face will fall into it." The chain of this hadith is sahih (authentic), but the two Shaykhs did not record it.