In the loose and obscure chronology of the times, I am guided by an authentic record, (in the book of ceremonies of Constantine Porphyrogenitus,) which certifies that, June 4, A.D. 638, the emperor crowned his younger son Heraclius, in the presence of his eldest, Constantine, and in the palace of Constantinople; that January 1, A.D. 639, the royal procession visited the great church, and on the 4th of the same month, the hippodrome.