He wrote, moreover, on theology, geography, natural history, and philology; but his most celebrated work is his 'Book of Animals,' in which he displayed all his knowledge of the Arabic tongue. He was frightfully ugly, and obtained the surname of Jahiz on account of his protuberant eyes. He himself informs us that the Khalif Mutwakkil intended to appoint him as tutor to his sons, but was deterred by his ugliness, and dismissed him with a present of ten thousand dirhems. Al-Jahiz died A.D. 869, over ninety years of age.
