Please note that Mommsen uses the AUC chronology (Ab Urbe Condita), i.e. from the founding of the City of Rome. You can use this reference table to have the B.C. dates
From: The History of Rome, by Theodor Mommsen
Translated with the sanction of the author by William Purdie Dickson
In close association with the comparatively considerable development of urban life stands the activity of intercourse by land and by water. Everywhere there were roads and bridges. The river-navigation, which streams like the Rhone, Garonne, Loire, and Seine, of themselves invited, was considerable and lucrative. But far more remarkable was the maritime navigation of the Celts. Not only were the Celts, to all appearance, the nation that first regularly navigated the Atlantic ocean, but we find that the art of building and of managing vessels had attained among them a remarkable development.
The navigation of the peoples of the Mediterranean had, as may readily be conceived from the nature of the waters traversed by them, for a comparatively long period adhered to the oar; the war-vessels of the Phoenicians, Greeks, and Romans were at all times oared galleys, in which the sail was applied only as an occasional aid to the oar; the trading vessels alone were in the epoch of developed ancient civilization "sailers" properly so called.(14)
14. We are led to this conclusion by the designation of the trading or "round" as contrasted with the "long" or war vessel, and the similar contrast of the "oared ships" (--epikopoi veies--) and the "merchantmen" (--olkades--, Dionys. iii. 44); and moreover by the smallness of the crew in the trading vessels, which in the very largest amounted to not more than 200 men (Rhein. Mus. N. F. xi. 625), while in the ordinary galley of three decks there were employed 170 rowers (III. II. The Romans Build A Fleet). Comp. Movers, Phoen. ii. 3, 167 seq.
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