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32 cola's seventh campaign closed with the summer of 84, he directed the fleet, which had hitherto accompanied the movements of his army, to proceed northward, and, besides striking terror in the still unconquered Caledonian tribes, to collect for him such information as he needed for his next movements in the summer of the ensuing year. Now it is important to bear in mind that the fleet began its voyage northwards at the beginning of autumn, and also that Roman mariners rarely, except under strong pressure, put out far to sea, but usually hugged the coast from headland to headland. Moreover, an expedition beginning after the short summer in that high latitude was past, would encounter the equinoctial gales near at hand. We have no reason to suppose that Agricola's ships did not return in good condition to their winter-harbour in the Forth: accordingly their exploring errand can hardly have occupied more than a few weeks, a period much too brief to allow not very bold or skilful sailors to circumnavigate so large an island, to say nothing of October tides, the fogs of the Irish Channel, and the fact that there were no charts to guide them, and possibly also no experienced or trustworthy pilots to be found. The opinion of Dean Merivale on this subject is favourable to a certain amount of new discovery, but adverse to a complete one. "The Roman mariners," he says, "now for the first time entered the Pentland Firth, surveyed and counted the Orkney Islands, and gained perhaps a glimpse of the Shetlands. They ascertained the point at which Britain terminates northward, and possibly noted the great deflection of the coast southward from Cape Wrath. Having effected the object