The expression of Tacitus, ‘æstuaria ac silvas ipse prætentare,’ shows that this was the scene of his campaign. It is only with reference to the west coast, south of the Clyde, that such an expression is applicable, and the Solway could hardly have been excluded from it. It will be afterwards shown that the Selgovæ who occupied its northern shore were a Brigantian tribe. Footnote 44: The position of the Roman camps and forts illustrates in a remarkable manner the expression ‘præsidiis castellisque circumdatæ.’ It must be kept in view, in following Tacitus’ narrative, that from the peculiarity of his style every word is pregnant with meaning, and has a precision which has been much overlooked. Footnote 45: Paullatimque discessum ad delenimenta vitiorum, porticus et balnea et conviviorum elegantiam.—TACIT. _in Vit. Ag._, c. 21. Footnote 46: Novas gentes aperuit. Footnote 47: 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. Footnote 48: ‘Quod tum præsidiis firmabatur.’ These were obviously different from and farther south than the forts mentioned in the previous campaign. The expression ‘summotis velut in aliam insulam hostibus’ is the significant one used in fixing the barrier between the provincial Britons and the Barbarians (see chap. ii. note ^{70}), and implies that Agricola’s intention was to add the conquered country south of the firths to the province. ‘Summotis’ does not here or elsewhere mean the actual driving out of the natives, but that those within the line of separation had ceased to be ‘hostes.’ Footnote 49: