Note 47 — Chapter I · ADVANCE OF THE ROMANS TO THE FIRTHS OF FORTH AND CLYDE.

That in this campaign the Roman arms reached the Firth of Tay is distinctly asserted by Tacitus, and his clear statement cannot be explained away. Agricola could only reach it by two routes,—either entirely by land through Stirlingshire and Perthshire, or across the Firth of Forth through Fife. The former is most probable, as Tacitus usually mentions crossing estuaries where it takes place; and the latter route is moreover plainly excluded, as the nations on the north shore of the Firth of Forth were still new to him in the sixth campaign.