---The historical cera of the Greeks which is dated from the 787th year before the Julian period; consequently, by the addition of 787 to any given year of the Julian period, the year of this aera may be obtained; and, on the other hand, by subtracting 787 from any year of this aera, the year of the Julian period may be obtained: hence, by the addition of 787 to 4714, the year of the Julian period corresponding with the birth of our Saviour, 5500, is obtained, the year of this 82rn, which corresponds with the first year of the vulgar aera. In like manner any years of this aera may be reduced to the years of the vulgar aera, and vice versa : thus, if from 7215, a given year of this aera, 5500 be subtracted, the remainder, 1715, will be the year of Christ; and if to the year 1715, 5500, the sum 7215 is the year of this aera.

—The ecclesiastical cera of the Greeks was dated 780 years before the Julian period, and consequently, by the addition of 4714 years, was 5494 years before the vulgar aera; this was otherwise called the Alexandrine aera, and was first employed by Panodorus, an ./Egyptian monk, in calculating the Easter and other ecclesiastical matters. To reduce the years of this aera to those of the vulgar aera, add or subtract 5493: thus, if 5493 be added to 1822, it gives7315, the year of the ecclesiastical aera; and if from 7208 be subtracted 5493, it leaves 1715, the year of the vulgar aera. To reduce, therefore, the years of this aera to those of the vulgar aera, and vice versa, add or subtract 5508: thus, if to the present year, 1822, be added 5508, it will give 7330, the year of this aera; and if from 7223, the given year of this aera, be taken 5508, it will leave 1715, the year of the vulgar aera.

— The civil (era of the Greeks, which was used by the Emperors of the East in their public acts, and has since been used by the Russians, is dated 795 years before the Julian period, and 5509 years before the vulgar sera