The reserve of the natives now descended, and endeavoured to outflank the Roman army and attack them in the rear, when Agricola ordered four squadrons of reserve cavalry to advance to the charge. The native troops were repulsed, and being attacked in the rear by the cavalry from the wings, were completely routed, and this concluded the battle. The defeat became general; the natives drew off in a body to the woods and marshes on the west side of the plain. They attempted to check the pursuit by making a last effort and again forming, but Agricola sent some cohorts to the assistance of the pursuers; and, surrounding the ground, while part of the cavalry scoured the more open woods, and part dismounting entered the closer thickets, the native line again broke, and the flight became general, till night put an end to the pursuit. Such was the great battle at ‘Mons Granpius,’ and such the events of the day as they may be gathered from the concise narrative of a Roman writing of a battle in which the victorious general was his father-in-law. The slaughter on the part of the natives was great, though probably as much overstated, when put at one-third of their whole army, as that of the Romans is under-estimated; and the significant silence of the historian as to the death or capture of Calgacus, or any other of sufficient note to be mentioned, and the admission that the great body of the native army at first drew off in good order, show that it was not the crushing blow which might otherwise be inferred. On the succeeding day there was no appearance of the enemy; silence all around, desolate hills and the distant smoke of burning dwellings alone met the eye of the victor; but, notwithstanding his success, he evidently felt that, with so difficult a country before him, and a native army probably re-assembling in the recesses of a mountain region, which, if gained, it would manifestly be impossible to retain, and knowing too somewhat better what the great barrier of the so-called Grampians was, both to the invading and the native army, he was in no condition to follow up his advantage. The attempt to subjugate the northern districts was substantially abandoned, and Agricola appears to have crossed the Tay and led his army into the country which he had overrun in the third year, and whose inhabitants are now termed ‘Horesti.’ Having taken hostages from them to prevent their joining the hostile army, he returned to his winter quarters south of the Firths of Forth and Clyde with his troops, while he directed his fleet to proceed along the coast to the north till they had encircled the island.