Ancient Britain and the Invasions of Julius Caesar. T. Rice Holmes
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kindred, unto you, the founders of our homes, we utter the gladness of our thanks.’18
Tertiary man.
The palaeolithic people had acquired a degree of skill in the manufacture of stone tools which is only attainable by the most practised modern imitators. But the progress which they made during the incalculably long period of their existence was so small that they must have needed ages to ascend to the level at which we are able to observe them. Therefore, although no skeletons, no implements have yet been found which can be referred, in the opinion of all experts, to the Tertiary Period, the most sceptical are willing to believe that man, even if he did not deserve the appellation of Homo sapiens, did then wander upon the face of the earth.19 But how, when he had assumed the erect position and had begun to make intelligent use of the hands which gave him such an advantage in contending with other carnivorous animals more powerful than himself, he learned slowly and by repeated efforts to chip the flints that he picked up into serviceable shapes; how in the struggle for a livelihood the stronger or the more cunning prevailed; how with developing intelligence came keener susceptibility to pain as well as to pleasure; how men’s fancies were quickened by light and darkness, sun, moon, and stars, and their fears excited by storm and flood and fire; how they strove to communicate to each other their alarms, their desires, and their joys—these things may only be imagined; and the imagination of those who have read most wisely and have most observantly studied the ways of modern savages will lead them least astray.
The Ice Age.
The Tertiary was merging into the Quaternary or Pleistocene Period when the climate which had before fostered the palms and crocodiles whose fossils have been discovered in the London Clay,20 but had been gradually changing, became intensely cold. Snow fell thickly upon the mountains of Scandinavia; glaciers began to creep down the valleys; and gradually the ice accumulated until it overspread the whole of Northern Europe, filled the basins of the Baltic and the North Sea, hid mountains and uplands in Scotland, and choked the dales of Northern England, of the Midlands, and of Wales; while isolated glaciers were formed even so far southward as the valleys of the Beaujolais and the Lyonnais. The ice has left its record upon the Highland and Cumbrian mountains, whose rugged crags it moulded into flowing curves; upon rocks which were scratched by stones embedded in slowly moving glaciers; in the mud, stiff and tenacious, which they deposited as they grided over many kinds of rocks, and which, being interspersed with stones, large and small, is called boulder-clay; in rocks which they transported and dropped far from their native sites, and by which the directions that they followed can still be traced; in moraines which mark the limits of their descent and their recession; in lakes that were formed, after the ice had disappeared, in glens which moraines had dammed;21 in the Arctic plants which survive on mountains, and in those whose fossil remains have been found in Norfolk near the level of the sea. In many places the boulder-clay lies in two or more layers, separated by stratified sands and gravels, from which it has been generally inferred that the Ice Age was interrupted by a period—here and there by short intervals—during which the climate was mild. Told briefly and in general terms, the tale which a learner might piece together from geological textbooks22 is something like this. The cold was most intense during the earlier stage, when the lower boulder-clay was being deposited, and, little by little, Britain rose until it became one with the Continent, with Ireland, and with Scandinavia, and extended far westward into the Atlantic Ocean. Then, we are told, the ice-sheet that covered Scandinavia was six thousand feet thick; and though it became thinner as it advanced southward, it shrouded the hill-tops in Scotland, where boulders were lifted right over the water-parting, and dropped on the western side, and scored its marks upon rocks in the Lake District at heights of two thousand five hundred feet; while, spreading over Ireland, it went out to sea beyond Cork and Kerry, where the wall of ice broke off and floated away in bergs. Then the land slowly sank until in the interglacial period only the hills stood out above the sea, and Great Britain became an archipelago. Again the movement was upward, though often interrupted and perhaps not general in extent: the climate was again becoming severe; and, although the rigours of the first period were not repeated, local glaciers crept down the higher valleys north of the Midlands, while icebergs floated over the parts that remained submerged and over the North Sea. Now too, as in the earlier period, the cold was not everywhere continuous: there were oscillations during which the glaciers alternately advanced and retreated. As the Ice Age was beginning to near its end, the land continued to rise until the North Sea, the English Channel, and the Irish Sea once more disappeared. In the latest stage of all, when Arctic conditions were about to vanish even in our northern latitudes, there was a gradual subsidence: Scotland was lowered about one hundred feet beneath the present level of the sea, as the highest ‘raised beach’ along the shores of the great estuaries testifies; and the waters rushed in over the sinking valley of the Dover Strait.
Such was the orthodox faith: but the rising geologists have discarded some of its articles; and even among the faithful there are pious doubters. Many authorities deny that the sea-shells which are found on hills in North Wales, Cheshire, and elsewhere, prove that they were once submerged: those shells, they insist, were ploughed up by glaciers out of the sea-floor; and they require us to believe that they were carried up the sides of the hills to heights of thirteen hundred and fifty feet above the sea-level.23 But although these shells are probably not in their original position, and the mere presence of marine organisms is no sufficient proof of former submergence, shells have been found near Inverness, five hundred feet above the sea, in the very place where they lived and died. Still, it does not follow that the submergence which they attest was interglacial.24 Some inquirers believe that the glaciers advanced and retreated once and no more;25 that there was only one slight elevation of the land and one slight subsidence: others that Britain was not only elevated twice, but also twice partially submerged; others that it was finally severed from the Continent in the earlier part of the Ice Age, when the drainage of Northern Europe, pouring into the North Sea and barred by the ice-sheet from escaping northwards, cut for itself a channel across the isthmus which now lies below the Dover Strait.26 One expert still insists that when man first entered Britain the whole country stood at least six hundred feet above its present level:27 another, in the same work, denies that its greatest elevation was more than seventy feet;28 and their editor looks helplessly on. One writer suggests that there may never have been an Ice Age, in the strictest sense of the term, at all, but only local glaciers, such as now exist in Greenland.29 Another has laboured to show that the accumulation of ice-sheets ‘merely marked one or more culminating epochs in a period when the climate was at least as commonly temperate as Arctic’.30 Others even now maintain that not one only, but five interglacial periods interrupted the intense cold;31 others again that there was no interglacial period at all, but only local ameliorations of climate.32 Another fertile theme of controversy has been the origin of the boulder-clays. But the confession of a Fellow of the Royal Society, who, as a member of the Geological Survey, lived in Norfolk for eight years, studying its geology, suggests that, after all, a sense of humour may compensate for inability to fathom the mysteries of the Ice Age. ‘After spending about a year in Norfolk,’ he says, ‘I began to believe I knew all about the drifts, but during the following seven years of my sojourn in that county, as I moved from place to place, I somehow seemed to know less and less, and I cannot say what would have been the result, but fortunately the geological survey of the county came to an end.’33 Fortunately, too, it is not essential to our study of palaeolithic man to decide in every case between the theories of rival geologists. All admit that in Britain the Thames was the extreme southern limit of glacial movement, although even in the southern fringe Arctic conditions prevailed; that glaciers covered a large part of the country north of the Thames, and on the higher regions coalesced into ice-sheets: the view that the lower boulder-clay was a moraine profonde has at last been generally adopted;34 while almost all agree that there was at least one interglacial period, and that there were climatic variations in certain tracts. Nevertheless one of the ablest and most experienced of our field geologists has recently given weighty reasons for his own conviction that even this solitary age of amelioration should not be regarded as an established fact.35
Continental Britain.
But, if we are to study the Palaeolithic Age intelligently, we must endeavour to test for ourselves the dogma that Britain was then continental. That dogma has recently been questioned by geologists who have minutely re-examined in the field the