Though the pagan philosophy had been much discouraged at Alexandria by the destruction of the temples and the cessation of the sacrifices, yet the philosophers were still allowed to teach in the schools. Syrianus was at the head of the Platonists, and he wrote largely on the Orphic, Pythagorean, and Platonic doctrines. In his Commentary on Aristotle's Metaphysics he aims at showing how a Pythagorean or a Platonist would successfully answer Aristotle's objections. He seems to look upon the writings of Plotinus, Porphyry, and Iamblichus as the true fountains of Platonic wisdom, quite as much as the works of the great philosopher who gave his name to the sect. Syrianus afterwards removed to Athens, to take charge of the Platonic school in that city, and Athens became the chief seat of Alexandrian Platonism. Olympiodorus was at the same time undertaking the task of forming a Peripatetic school in Alexandria, in opposition to the new Platonism, and he has left some of the fruits of his labour in his Commentaries on Aristotle. But the Peripatetic philosophy was no longer attractive to the pagans, though after the fall of the catechetical school it had a strong following of Christian disciples. Olympiodorus also wrote a history, but it has long since been lost, with other works of a second-rate merit. He was a native of the Thebaid, and travelled over his country. He described the Great Oasis as still a highly cultivated spot, where the husbandman watered his fields every third day in summer, and every fifth day in winter, from wells of two and three hundred feet in depth, and thereby raised two crops of barley, and often three of millet, in a year. Olympiodorus also travelled beyond Syene into Nubia, with some danger from the Blemmyes, but he was not able to see the emerald mines, which were worked on Mount Smaragdus in the Arabian desert between Koptos and Berenice, and which seem to have been the chief object of his journey. Proclus came to Alexandria about the end of this reign, and studied many years under Olympiodorus, but not to the neglect of the platonic philosophy, of which he afterwards became such a distinguished ornament and support. The other Alexandrians under whom Proclus studied were Hero, the mathematician, a devout and religious pagan, Leonas, the rhetorician, who introduced him to all the chief men of learning, and Orion, the grammarian, who boasted of his descent from the race of Theban priests. Thus the pagans still held up their heads in the schools. Nor were the ceremonies of their religion, though unlawful, wholly stopped. In the twenty-eighth year of this reign, when the people were assembled in a theatre at Alexandria to celebrate the midnight festival of the Nile, a sacrifice which had been forbidden by Constantine and the council of Nicsea, the building fell beneath the weight of the crowd, and upwards of five hundred persons were killed by the fall. [Illustration: 271.jpg ARABS RESTING IN THE DESERT]