Claudius Ptolemaeus (approx. 100 - approx. 180 AD.) also known as Ptolemy, was a cartographer, geographer and astronomer working in Alexandria, whose research has had a sustainable influence on science up until modern times. Ptolemy was working at the museum in Alexandria, which had one of the most important libraries of the Ancient World, which also provided him with the best basis for his extensive research in the fields of astronomy, geography, optics etc. His "Mathematike syntaxis" is undoubtedly one of the most important books on astronomy of the late Middle Ages and the early modern age (first printed in Venice in 1496).
The theory of a geocentric universe presented in this book was only replaced in the 16th century by Copernicus' idea of a heliocentric solar system with the sun and not the earth in the center of the universe.
In his second most important work, "Geographike Hyphegesis", which comprised a total of eight books, he wrote an introduction to cartography with the aim of drawing a representation of the entire hitherto known surface of the earth.
He picked up where Marinus of Tyre had left off in a work that no longer remains today, who had projected a right-angled grid system on a comprehensive list of place names to receive so-called flat maps. In the first book Ptolemy explained an alternative projection process, which takes the curvature of the meridians and parallels into account.
Books 2 to 8 provide a list of coordinates of over 8,000 locations on the surface of the earth known in his time. Only the appearance of Dutch cartographies by Ortelius and Mercator changed the modern maps of countries compared to that to Ptolemy.
The first incunable editions of the ptolemaeic geography appeared in Vincenza in 1475 (without maps), in Bologna in 1477 and with copperplate engravings of the maps in Rome.