definite meanings possibly be attached to the various parts of a line so minutely graduated, that the centre of the fire kindled on any one graduation could be scarce ten feet apart from the centre of the fire kindled on any of its two neighboring graduations? Even by day, the exact compartment which a fire occupied could not be distinguished, at the distance of half a mile, from its neighboring compartments, and not at all by night, at any distance, from even the compartments farthest removed from it. Who, for instance, at the distance of a dozen miles or so, could tell whether the flame that shone out in the darkness, when all other objects around it were invisible, was kindled on the east or west end of an eminence little more than a hundred yards in length? Nay, who could determine,--for such is the requirement of the hypothesis,--whether it rose from a compartment of the summit a hundred feet distant from its west or east end, or from a compartment merely ninety or a hundred and ten feet distant from it? The supposed signal system, added to the mere beacon hypothesis, is palpably untenable. The theory of Williams, however, which is, I am inclined to think, the true one in the main, seems capable of being considerably modified and improved by the hypothesis of Sir George. The hill-fort,--palpably the most primitive form of fortalice or stronghold originated in a mountainous country,--seems to constitute man's first essay towards neutralizing, by the art of fortification, the advantages of superior force on the side of an assailing enemy. It was found, on the discovery of New Zealand, that the savage inhabitants had already learned to erect exactly such hill-forts amid the fastnesses of that country as those which were erected two thousand years earlier by the Scottish aborigines amid the fastnesses of our own. Nothing seems more probable, therefore, than that the forts of eminences such as Craig Phadrig and Knock Farril, originally mere inclosures of loose, uncemented stones, may belong to a period not less ancient than that of the first barbarous wars of Scotland, when, though tribe battled with tribe in fierce warfare, like the red men of the West with their brethren ere the European had landed on their shores, navigation was yet in so immature a state in Northern Europe as to secure to them an exemption from foreign invasion. In an after age, however, when the roving Vikings had become formidable, many of the eminences originally selected, from _their inaccessibility_, as sites for hill-forts, would come to be chosen, from _their prominence in the landscape_, as stations for beacon-fires. And of course the previously erected ramparts, higher always than the inclosed areas, would furnish on such hills the conspicuous points from which the fires could be best seen. Let us suppose, then, that the rampart-crested eminence of Knock Farril, seen on every side for many miles, has become