Let us suppose that the calendar which, as we may learn from the astrological tablets, was already in Sargon’s time a well known and venerated institution, had been originally drawn up at a date much earlier than Sargon’s, when the first month (Bar zig-gar), was not the first _spring_ month, but when it was the first _winter_ month of the year. This date (see Plate I., fig. 1) would have been about 6,000 B.C.; for then the sun entered the constellation Aries at the _winter solstice_--a season equally well, if not better suited than the spring equinox to hold the first place in the calendar.[8] Under this supposition, it would no longer be difficult to imagine why the ancient Accadian astronomers should have chosen Aries as the first constellation of the Zodiac, and Nisan (Bar zig-gar) as the first month, and the “beginning of the year.” [8] After this paper had appeared in the _Proceedings of the Society of Biblical Archæology_, a corroboration of this opinion occurred to the writer’s mind, suggested by a further study of the month names in the Accadian calendar. It is as follows:-- The twelfth month is named “sowing of seed.” Seed may be and is, sown in many latitudes in _spring_, and also in _winter_ time. “Sowing of seed” might therefore describe a month at the ending of an equinoctial or of a solstitial year: but the thirteenth (_i.e._ the occasionally intercalated) month is named that of “dark sowing.” This epithet _dark_, added to the “sowing” of the twelfth month, very plainly points to a solstitial or midwinter ending of the year. The thirteenth month in a luni-solar year, whose beginning should be bound to the vernal equinox, must always cover some of the concluding days of March and some of the first days of April; and those days are certainly much _lighter, not darker_ than those of the preceding month, covering parts of February and March, whereas, the thirteenth intercalary month in a luni-solar year, whose beginning should be bound to the winter solstice, must always cover the concluding days of December and those at the beginning of January; and might well be distinguished by the epithet _dark_, not only from the days of the preceding month, but indeed from those of any other month of the year (see Plate I., figs. 1, 2.) It is of interest here to note that this insistence in Accadian month nomenclature on the darkness of the thirteenth month, tends to confirm the already formed opinion of scholars, that the Accadians were not indigenous to Babylonia, but had descended into it from more northern latitudes, where darkness is a more marked concomitant of winter than in the nearly tropical latitude of Babylonia.