A vibrant and evocative account of how the great scientific ideas of the ancient world were lost and found. 'A lovely debut from a gifted young author. Violet moller brings to life the ways in which knowledge reached us from antiquity to the present day in a book that is as delightful as it is readable.' Peter Frankopan, author of the silk roads 'an endlessly fascinating book, rich in detail, capacious and humane in vision.' Stephen Greenblatt, author of the swerve: how the world became modern in the map of knowledge Violet moller traces the journey taken by the ideas of three of the greatest scientists of antiquity - Euclid, Galen and Ptolemy - through seven cities and over a thousand years. In it, We follow them from sixth-century Alexandria to ninth-century Baghdad, from Muslim Cordoba to Catholic toledo, from salerno's medieval medical school to Palermo, capital of Sicily's vibrant mix of cultures, and - finally - to Venice, where that great merchant city's printing presses would enable Euclid's Geometry, ptolemy's system of the stars and galen's vast body of writings on medicine to spread even more widely. In tracing these fragile strands of knowledge from century to century, from East to West and North to South, moller also reveals the web of connection between the Islamic world and Christendom, connection that would both preserve and transform astronomy, Mathematics and medicine from the early middle Ages to the Renaissance. Vividly told and with a dazzling cast of characters, the map of knowledge is an evocative, nuanced and vibrant account of our common intellectual heritage.