There is a much more definite note of time in Cat. vi. § 20, where speaking of Manes Cyril says:  “The delusion began full seventy years ago.”  If we may assume that the outbreak of this heresy is to be dated from the famous disputation between Archelaus and Manes in 277 Cat. vi. § 27., it follows that Cyril must have made this statement in 347 or 348.  And further, if Dr. Routh Rell. Sac. v. p. 12. is correct in fixing the date of the Disputation between July and December 277, the Lent in which the Lectures were delivered must have been, as Touttée decides, that of 348, not of 347, as Tillemont had supposed.