" Bartimaeus: By-name of the demon Sakhr al-Jinni, mentioned in Procopius and Michelot. A middle-ranking djinni of ancient standing, great ingenuity, and no little power. First recorded in Uruk; later in Jerusalem. Fought at the battle of al-Arish against the Assyrians. Known masters have included: Gilgamesh, Solomon, Zarbustibal, Heraclius, Hauser. "

― Jonathan Stroud , Ptolemy's Gate (Bartimaeus, #3)