 In 1649, the Latin phrase "annus æræ Christianæ" appeared in the title of an English almanac.A 1652 ephemeris is the first instance found so far of the English use of "Christian Era".The English phrase "common Era" appears at least as early as 1708, and in a 1715 book on astronomy it is used interchangeably with "Christian Era" and "Vulgar Era".