Entitled 'The Book of Curiosities of the sciences and marvels for the eyes', this treatise is a compilation of earlier works including otherwise lost 9th–11th-century works by Muslim astronomers, geographers and travellers. Divided into 2 parts, the 1st half concerns celestial bodies with a focus on astrology and divination, while the 2nd concerns the earth. For the rectangular world map shown here, Geography by Claudius Ptolemy and the scholars commissioned c.830 by the Abbasid caliph Al-Ma’mun are cited as sources. North is at the bottom. At right are the Atlantic coasts of West Africa and the Iberian peninsula, and at left China. The Nile Delta is nearly in the centre while the southern sources of the Nile are at the top. The author’s considerable knowledge of the Nile Delta and his use of Coptic vocabulary, as well as his recognition of the authority of the Ismaili Fatimid caliphs of Cairo, suggest that Egypt was the location of the work’s production. This is the earliest rectangular world map to survive from before the Renaissance, and its graduated scale along the top is unique in the history of cartography up until the 14th century.