And this line Agricola seems to have destined as the boundary of the Empire.

For though in the following year he carried his arms further, and, as it is thought, to the foot of the Grampian Mountains, and there defeated a confederate army of the Caledonians, headed by Galgacus, one of their most famous chiefs, yet he built no fort to the northward of this line: a measure which he never omitted, when he intended to preserve his conquests.

The expedition of that summer was probably designed only to disable the Caledonians from attempting anything against this barrier.

But he left them their mountains, their arms, and their liberty: a policy, perhaps, not altogether worthy of so able a commander.

He might the more easily have completed the conquest of the whole island by means of the fleet which he equipped to cooeperate with his land forces in that expedition.