purchase of a field for a burial place for strangers.[310] After leaving what was once the home of the Patriarchs we saw little of interest until we reached Nisibis. But Nisibis, like Haran, is interesting rather for what it was in the distant past than for what it is at present. Like Haran, it was once a busy and commanding mart between the East and the West. Now, however, like Haran, it is little more than a mass of ruins which are eloquent witnesses of ancient power and splendor. This is evidenced by the remaining arches of a great bridge across the Gargar on which the city was built and by the crumbling walls and columns of a great cathedral whose florid Corinthian ornaments remind one of those which so distinguish the famous temples of Baalbec and Palmyra. As I contemplated the three or four hundred hovels which make up modern Nisibis, it seemed difficult to believe that it was once a city of palaces and schools and the great bulwark of Rome in Mesopotamia against Persians and Parthians, and that it was for centuries compelled to endure a constant change of rulers. The Armenians, to begin with, took it from its founders. Lucullus, after a long siege, captured it from Tigranes. After the crushing defeat and death of Crassus at Haran,[311] the Parthians wrested it from the Romans. It next fell into the power of Trajan and under Septimus Severus became a stronghold of the Roman colony established in these parts. Sapor I became master of it in the year 242, but it was soon retaken by the Romans under Gordianus III Diocletian and Maximian, recognizing the importance of this strategic point and foreseeing that it would inevitably be subject to the attacks of the enemy, had it strongly fortified. Ammianus Marcellinus gives us some idea of the formidable character of its fortifications when he declares that Nisibis had served the Orient as a barrier against the invasion of the Persians.[312] But Nisibis was not only a stronghold of the utmost importance to the nation that controlled it; it was also a literary center whose fame extended to Africa and Italy and whose schools were as celebrated for certain of their courses of study as were those of Rome and Alexandria.[313] When the famous school of Edessa was closed in 489 by Bishop Cyrus and the Emperor Zeno on account of its Nestorian tendencies, its teachers and students repaired to Nisibis, where they became the most zealous advocates of Nestorianism as they subsequently became its most active propagators in Persia.