But if pre-Glacial man is thus separated from the origin of the race by a very long interval indeed, it is none the less true that he is separated from our own time by the intervention of a vast blank space, the space occupied by the coming on and passing away of the Glacial Epoch. A great gap cuts him off from what we may consider as the relatively modern age of the mound-builders, whose grassy barrows still cap the summits of our southern chalk downs. When the great ice sheet drove away palaeolithic man--the man of the caves and the unwrought flint axes--from Northern Europe, he was still nothing more than a naked savage in the hunting stage, divinely gifted for art, indeed, but armed only with roughly chipped stone implements, and wholly ignorant of taming animals or of the very rudiments of agriculture. He knew nothing of the use of metals--_aurum irrepertum spernere fortior_--and he had not even learnt how to grind and polish his rude stone tomahawks to a finished edge. He couldn't make himself a bowl of sun-baked pottery, and, if he had discovered the almost universal art of manufacturing an intoxicating liquor from grain or berries (for, as Byron, with too great anthropological truth, justly remarks, 'man, being reasonable, _must_ get drunk'), he at least drank his aboriginal beer or toddy from the capacious horn of a slaughtered aurochs. That was the kind of human being who alone inhabited France and England during the later pre-Glacial period. A hundred and seventy thousand years elapse (as the play-bills put it), and then the curtain rises afresh upon neolithic Europe. Man meanwhile, loitering somewhere behind the scenes in Asia or Africa (as yet imperfectly explored from this point of view), had acquired the important arts of sharpening his tomahawks and producing hand-made pottery for his kitchen utensils. When the great ice sheet cleared away he followed the returning summer into Northern Europe, another man, physically, intellectually, and morally, with all the slow accumulations of nearly two thousand centuries (how easily one writes the words! how hard to realise them!) upon his maturer shoulders. Then comes the age of what older antiquaries used to regard as primitive antiquity--the age of the English barrows, of the Danish kitchen middens, of the Swiss lake dwellings. The men who lived in it had domesticated the dog, the cow, the sheep, the goat, and the invaluable pig; they had begun to sow small ancestral wheat and undeveloped barley; they had learnt to weave flax and wear decent clothing: in a word, they had passed from the savage hunting condition to the stage of barbaric herdsmen and agriculturists. That is a comparatively modern period, and yet I suppose we must conclude with Dr. James Geikie that it isn't to be measured by mere calculations of ten or twenty centuries, but of ten or twenty thousand years. The perspective of the past is opening up rapidly before us; what