Career

He is noted for excavating the temple of Mithras beneath the Basilica of San Clemente in Rome. In 1849 Mullooly became lector in Sacred Theology at the College of Saint Thomas in Rome, the future Pontifical University of Saint Thomas Aquinas, Angelicum. Mullooly wrote Saint Clement, Pope and Martyr, and His Basilica in Rome about the excavation project at San Clemente.