XXVII The Museum and Library at Alexandria BEFORE the time of Alexander Greeks had already been spread- ing as merchants, artists, officials, mercenary soldiers, over most of the Persian dominions. In the dynastic disputes that followed the death of Xerxes, a band of ten thousand Greek mer- cenaries played a part under the leadership of Xenophon. Their return to Asiatic Greece from Babylon is described in his Retreat of the Ten Thousand, one of the first war stories that was ever written by a general in command. But the conquests of Alexander and the division of his brief empire among his subordinate generals, greatly stimulated this permeation of the ancient world by the Greeks and their language and fashions and cultiu-e. Traces of this Greek dis- semination are to be found far away in central Asia and in north- west India. Their influence upon the development of Indian art was profound. For many centuries Athens retamed her prestige as a centre of art and culture ; her schools went on indeed to 529 a.d., that is to say for nearly a thousand years ; but the leadership in the intellec- tual activity of the world passed presently across the Mediterranean to Alexandria, the new trading city that Alexander had founded. Here the Macedonian general Ptolemy had become Pharaoh, with a court that spoke Greek. He had become an intimate of Alexander before he became king, and he was deeply saturated with the ideas of Aristotle. He set himself, with great energy and capacity, to organize knowledge and investigation. He also wrote a history of Alexander's campaigns which, unhappily, is lost to the world. Alexander had already devoted considerable sums to finance the enquiries of Aristotle, but Ptolemy I was the first person to make a permanent endowment of science. He set up a foundation in Alexandria which was formally dedicated to the Muses, the Museum of Alexandria. For two or three generations the scientific work done at Alexandria was extraordinarily good. Euclid, Eratosthenes who measured the size of the earth and came within fifty miles of its true diameter, Apollonius who wrote on conic sections, Hipparchus who 144
