Returning from the west country, Agricola entered upon the campaign of three years' duration, which issued in the Battle of Mons Grampus, the crowning glory of his arms in Scotland, and the immediate occasion of his recall. He chose the alternative route this time. From his chain of forts he could see the broad expanse of the Firth of Forth, the coast of Fife, the central Lomonds, and the distant hill-country, whose acquaintance he had already made. That distant point was the goal of his endeavour, and the shortest way to it was across the Firth of Forth, through the western division of Fife, and on by one of the Ochil passes--Glendevon, or some other further east into Strathearn. There was no time to lose. For, while he was engaged in the subjugation of Fife, the fleet, after exploring the harbours, had doubled the East Neuk, passed safely through St Andrews Bay, and entered the Firth of Tay. Its unexpected appearance caused the greatest consternation among the Caledonians. The immediate result was to greatly increase the peril in which the devoted garrisons in Strathearn stood. So great was their danger, and so well was it known, that there were those with Agricola who advised a retreat to the chain of forts between the Firths. But Agricola was not to be shaken in his resolve, which was to finally break the power of the tribes who dwelt to the north and east of the Grampians, and who, so long as they remained free and unchastised, were a standing menace to the Strath of the Earn and to the garrisons who held it at the hazard of their lives. He formed a camp to winter in at a place called Grassy Walls, on the east side of the Tay, near to Perth. But there was still time, before the winter set in, for a little exploration and a brush with the enemy to revive the courage of his soldiers, which had begun to droop a little. Advancing northward on the left bank of the river, Agricola reached the Isla, and not caring to cross it so late in the year, in the face of the enemy who were massed upon the Hill and Muir of Blair beyond, he diverged to the right, following the course of the Isla until he came to the place where Coupar Angus stands now. Here he paused. He had marched from Perth in three divisions to prevent surprise, and in this neighbourhood there are three positions marked by Roman remains that correspond with these divisions. The main force was stationed at Coupar Angus; the Ninth Legion at Lintrose, two miles south-east; a third small body at a place two miles south-west, overlooking the Tay, and guarding the passage. These details are important, as helping to determine the true site of the Battle of Mons Grampus. It may be taken for granted that the Roman General made good use of his opportunity to survey the ground upon which the decisive battle was fought. Before retiring to winter quarters at Grassy Walls, the Roman soldiers had a chance given them of testing the strength and valour of the Caledonians. The Ninth