Sahih Bukhari

Narrated Ibn 'Abbas: (regarding) the explanation of ""... It throws sparks as Al-Qasr ..."" (V. 77:32): We used to collect logs of wood, three cubits long or longer, to store for heating purposes in winter, and we used to call it Al- Qasr, it also means a castle or a fort. ""As if they were Jimalatun Sufr (yellow camels or bundles of ropes)"" (V.77:33): means the ropes of a ship which are made in bundles till it become as wide as men's waists