Note 3582 — THE JULIAN CALENDAR AND THE CHRONOLOGY OF CAESAR’S INVASIONS OF BRITAIN

Cf. Unger (Neue Jahrbücher für Philologie, &c., cxxix, 1884, p. 586), and Zumpt (Jahrbücher für classische Philologie, vii Supplementband, 1873-5, p. 564).

Bergk (ib., 13 Supplementband, 1884, p. 618), remarking that Napoleon admits that Caesar quitted Britain in 55 B.C. as early as the 12th of September, says that the rise of Arcturus, which, according to Pliny (Nat. Hist., xviii, 31 [74], § 310), took place on that day, marked the commencement of the stormy season, and that it is therefore inconceivable that Caesar would have postponed his departure until the middle of the month. I do not attach the least importance to this argument. Caesar went by the equinox, not by the rise of Arcturus, and he waited as long as he thought safe. Moreover, Bergk apparently forgets that the date fixed by Pliny for the rise of Arcturus was borrowed from the Julian calendar, the astronomical calculations for which were not made until 46 B.C. [It should be noted that, according to Columella (De re rust., xi, 2), whom Bergk also quotes, the rise of Arcturus took place on the 17th of September, but the 13th presaged the approach of stormy weather (tempestatem significat).]