[a.d. 200–232–245.] In a former volume, strengthened by a word from Archbishop Usher, I have not hesitated to claim for Theophilus of Antioch a primary place among Christian chronologists. It is no detraction from the fame of our author to admit this, and truth requires it. But the great Alexandrian school must again come into view when we speak of any considerable achievements, among early Christian writers, in this important element of all biblical, in fact, all historical, science. Africanus was a pupil of Heraclas, and we must therefore date his pupilage in Alexandria before a.d. 232, when Dionysius succeeded Heraclas in the presidency of that school. It appears that in a.d. 226 he was performing some duty on behalf of Emmaus (Nicopolis) in Palestine; but Heraclas, who had acted subordinately as Origen's assistant as early as a.d. 218, could not have become the head of the school, even provisionally, till after Origen's unhappy ordination. Let us assume the period of our author's attending the school under Heraclas to be between a.d. 228 and a.d. 232, however. We may then venture to reckon his birth as circa a.d. 200. And, if he became "bishop of Emmaus," it could hardly have been before the year 240, when he was of ripe age and experience. He adds additional luster to the age of Gregory Thaumaturgus and Dionysius, as well as to that of their common mother in letters and theology, the already ancient academy of Pantænus and of Clement.