It is worthy of note that Chrysostom and Basil were the first to mark out definite lines of Christian instruction. During this period, also, the first songs of the Christian Church originated in the huts and caves of the poor. Thus in religious instruction and church song the foundations of the Christian common school were laid. =Catechetical Schools.=--The principal catechetical school was established at Alexandria A.D. 181, by Pantaenus. Others were located later at Antioch, Odessa, and Nisibis. The Alexandrian school, however, was by far the most important. Alexandria, at the close of the second century, was the seat of philosophy, as Athens had formerly been. It possessed the most important library in the world, and students and sages from all parts of the world flocked to this place of learning. Laurie says, "The great Alexander, in founding Alexandria, connected Europe, Asia, and Africa, not merely by mercantile bonds, but in their intellectual and literary life. Here arose, under the Ptolemies, a complete system of higher instruction, and libraries such as the world had not before seen. The books were lodged in the temple of Serapis, and accumulated to the number of seven hundred thousand. They formed the record of all human thought, until they fell a prey to internal civic and religious dissensions. The Serapeum dates from B.C. 298, and, after recovering from the fire of B.C. 48, it finally disappeared about A.D. 640." Under the stimulus of these surroundings, and with such an abundance of literary material at command, pagans and Christians vied with each other in their search for truth. But the pagans had better schools and better means of preparing themselves for intellectual combat. Christian teachers were called upon to defend their faith against subtle philosophers and trained thinkers, who had had the advantage of excellent schools. In order to meet this apparent defect and fortify themselves against their skillful opponents, the Christians established the catechetical school at Alexandria, the most celebrated school of its kind at that period. It took the name _catechetical_ from the fact that the method of instruction was largely that of catechising, though lectures were also given. Many pagans had been converted to Christianity, and it was necessary that they should be taught the reason of their faith, in order that they might maintain their ground when they came in contact with unbelievers. This was particularly necessary, if Christianity was to hold its own, in a city like Alexandria, where so many learned men had gathered. It was also necessary for the extension of the new faith among men of superior intelligence. Thus the object of the catechetical school was to instruct learned men in the doctrines and usages of the Church, to prepare believers to meet the arguments of the philosophers, and to train teachers.