terrorem.  This occurred in the year 277, and the anniversary was commemorated as the great religious festival of the Manichæans. This is not the place to attempt any account or criticism of the strange eclecticism of Mani.28  An adequate idea of the system may be gathered from the accompanying treatises.  It may, however, be desirable to give some account of the original sources of information regarding it. We study the systems of heresiarchs at a disadvantage when our only means of ascer- taining their opinions is from the fragmentary quotations and hostile criticism which occur in the writings of their adversaries.  Such, however, is our only source of information regard- ing the teaching of Mani.  Originally, indeed, this heresy was specially active in a literary direction, assailing the Christian Scriptures with an ingenuity of unbelief worthy of a later age, and apparently ambitious of promulgating a rival canon.  Certainly the writings of its early supporters were numerous;29 and from the care and elegance with which they were transcribed, the sumptuous character of the manuscripts, and the mysterious emblems with which they were adorned, we should fancy it was intended to inspire the people with respect for an authoritative though as yet undefined code.  It is, indeed, nowhere said or implied that the sacred books of the Manichæans were reserved for the eye only of the initiated or elect; and their reception of the New Testament Scriptures (subject to their own revision and emendation) would make it difficult for them to establish any secret code apart from these writings.  They were certainly, however, doctrines of an esoteric kind, which were not divulged to the catechumens or hearers; and many of their books, being written in Persian, Syriac, or Greek, were practically unavailable for the instruction of the Latin speaking pop- ulation.  It was not always easy, therefore, to obtain an accurate knowledge of their opinions.  Commentaries on the whole of the Old and New Testaments were written by Hierax;30 a Theosophy by Aristocritus; a book of memoirs, or rather Memorabilia, of Mani, and other works, by Heraclides, Aphthonius, Adas, and Agapius.  Unfortunately all of these books have perished, whether in the flames to which the Christian authorities commanded that all Manichæan books should be consigned, or by the slower if not more critical and impartial processes of time. 28 Böhringer characterizes it briefly in the words:  "Es ist der alte heidnische Dualismus mit seiner Naturtheo- logie, der in Mani’s Systeme seine letzten Kräfte sammelt und unter der gleissenden Hülle christlicher Worte und Formen an den reinen Monotheismus des Christenthums und dessen reine Ethik sich heranwagt " 29 Aug. c. Faustum, xiii. 6 and 18.  [See full list of Mani’s writings in Kessler’s art. in Herzog, R.E.—A.H.N.] 30 Lardner, however, seems to prove that Hierax was not a Manichæan, though some of his opinions approx- imated to this heresy.  The whole subject of the Manichæan literature is treated by Lardner (Works, iii. p. 374), with the learning of Beausobre and more than Beausobre’s impartiality. 48 Preface to the Anti-Manichæan Writings.