The most famous library of antiquity. Located in Alexandria, it was the principal center of Hellenistic culture under the Ptolemies, and contained hundreds of thousands of rolls. Among its earliest librarians were Callimachus and Apollonius of Rhodes. In his Caesar and Cleopatra (1899), G. B. Shaw treats humorously the burning of the library by Julius Caesar. It was burned and partly consumed in 391; in 642, according to a dubious legend, the caliph Omar seized the city and used the library's books to " heat the baths of the city for six months. " It is said that it contained 700,000 volumes, and the reason given by the Muslim destroyer for the destruction of the library was that the books were unnecessary in any case, for all knowledge that was necessary to man was contained in the Koran, and any knowledge contained in the library that was not in the Koran must be pernicious. Most modern experts, however, agree that the story of the library 's destruction by Omar is probably apocryphal. See Aristarchus.