In Scotland the story of the stones is slightly different. A great many of these are no doubt cat stones or battle memorials, but as they have not even Ogham inscriptions, they tell no tale. It is doubtful, indeed, if an Ogham inscription could describe a battle, or anything more complex than a genealogy, and still more so if it did whether we could read it. But without it how can we say what they are? If, for instance, the battle of Largs had not been fought in historic times, how could we tell that the tall stone that now marks the spot was erected in the thirteenth century? Or how, indeed, can we feel sure of the history of any one? By degrees, however, in Scotland they faded into those wonderful sculptured stones which form so marked and so peculiar a feature of Pictland. Whether we shall ever get a key to the hieroglyphics with which these stones are covered is by no means clear, but even if we do they probably will not tell us much. They certainly contain neither names nor dates, but even now their succession can be made out with tolerable distinctness. The probability seems to be that the figures on them are tribal marks or symbols of rank, and, as such, would convey very little information if capable of being read.
It is easy to trace the perfectly plain obelisk being developed into such as the Newton stones, which have only one or two Pagan symbols, but are certainly subsequent to the Christian era. From these we advance to those on the back of which the Christian cross timidly appears, and which certainly date after St. Columba's time (A.D. 563), and from that again to the erection of Sweno's stone, near Forres, in the first years of the eleventh century, where the cross occupies the whole of the rear, and an elaborate bas-relief supersedes the rude symbols in the front.
In Ireland the rude stones do not appear to have gone through the "symbol stage," but early to have ripened into the sculptured cross, for it was not from a timidly engraved cross as in Scotland that they took their origin. The Irish crosses at once boldly adopted the cross-arms, surrounded by a glory, with the other characteristics of that beautiful and original class of Christian monuments.