ARCHEOLOGY 335 involving the consequent existence of man in remote geolo gical eras, so far as all actual evidence can yet guide us, it is correct to say that, geologically speaking, the entire history of man is embraced in one period. But in the works of art, which form the bases of archaeological induction, a new element that of mind, or the reasoning faculty, along with the imitative and social arts is introduced, and greatly complicates its subdivisions. The stone period of Britain or Denmark is analogous to that of the Polynesian Islands. So closely do their tools and weapons resemble each other that it requires a practised eye to distinguish the stone axe or flint lance-head found in an ancient British barrow from implements brought by some recent voyager from the islands of the Southern Ocean. Nor could the most experienced archaeologist undertake in eveiy case to discriminate between the flint arrow-head dug from some primitive barrow of undated centuries before the Christian era, and the corresponding weapon brought by some recent traveller from Tierra del Fuego or regions beyond the Rocky Mountains. The inference is therefore legitimate, that in those Polynesians, Fuegians, or Indians of the North -West, we have examples of tribes in the same primitive stage as were the aborigines of Europe during its .stone period. Chronologically, however, the stone period of Europe and that of the Pacific islands or the American continent are separated by thousands of years. In like manner, the bronze age of Mexico was undisturbed by all later elements when first brought into contact with the matured civilisation of Europe in the 16th century, while the close of that of Britain preceded the 1st century of our era. The same rule is applicable to the primitive archaeology of all countries ; and a fertile source of error iind misconception has already had its rise in the assump tion that because Greece and Italy, Germany, Gaul, Scandinavia, and Britain, have all had their primitive stone and bronze periods, therefore the whole must have been contemporaneous. It cannot therefore be too strongly enforced as one of the most essential points of variance in the reasoning of the geologist and the archaeologist, that the periods of the latter, though synonymous, are not neces sarily synchronous ; but that, on the contrary, nearly all the phenomena which pertain to the natural history of man, and to the historic development of the race, may be witnessed in their various stages in contemporary races of our own day from rudimentary barbarism, and the absence of all arts essential to the first dawn of civilisation, to a state of greatest advancement in the knowledge and employment of such arts. Some progress has already been made in an approxi mation to certain chronological data of much importance relative to such primitive periods of the history of nations. But the archaeologist, as well as the geologist, is learning to deal with periods of time which cannot always be measured either by years or centuries, but rather must be gauged by those chronological stages in the history of our planet in which epochs and periods take the place of definite subdivisions of solar time. Nevertheless, geological evidence of changes which are known to have occurred within the historic period supplies an important key to the approximate duration of certain eras characterised by traces of human art ; and while by the intelligent observation of such remains in the superficial strata, mingling with the fossil evidences of extinct and familiar species of animal life, the link is supplied by which man takes his place in im unbroken chain of creative existence, sweeping back into so remote a past, the evidences of matured art pertain ing to periods unrecorded by history supply later links of the same chain, and reunite the present with all former ages. The system of primitive archaeology which is found appli cable to British antiquities so closely corresponds in all its essential features to that of Europe prior to the era of authentic history, that the purpose of such an abstract as this will be most conveniently accomplished by presenting its leading points as examples of the whole, illustrating these in passing by the analogous remains discovered in other countries. The apparent simplicity of a primitive stone period has been considerably modified by recent research ; and the careful study of the remains of ancient art, in their relation to accompanying geological phenomena, or of the evidences of artificial deposition in caves, barrows, chambered cromlechs, cairns, or other sepulchral structures, suggests the subdivision of prehistoric archaeology into a succession of epochs included within the period of non- metallurgic arts. But before defining the archaeological subdivisions of time it is indispensable to glance at the palaeontological elements of the question, and the evidences they supply in relation to comparative chronology. One of the most re markable phenomena affecting the conditions of life in Europe in recent geological epochs is the existence of a period, of long duration throughout the northern hemi sphere, of a temperature resembling that of the Arctic regions at the present time. After a period more nearly approximating in its conditions the heat of the tropics at the present day, though otherwise under varying states to wards the end of the tertiary epoch the temperature of the whole northern hemisphere gradually diminished, until the mountainous regions of Scotland and Wales then pro bably of a much higher elevation resembled Greenland at the present time; and this Arctic temperature gradually extended southwards to the Alps and the Pyrenees. The glaciers formed under the influence of perpetual frost and snow descended from_ those and other mountains into the valleys and plains over the greater portion of central Europe and northern Asia ; and this condition of things, pertaining to what is known as the glacial period, was one of greatly prolonged duration. After some partial modifications of this low temperature, and a consequent advance and retrocession of the glacial influences in France and elsewhere, along what was then the border lines of a north temperate zone, the glacial period drew to a close ; a gradual but persistent rise of temperature carried the lines of ice and perpetual snow further and further northward, excepting in regions of great elevation, as in the Swiss Alps. This was necessarily accompanied by the melting of the vast glaciers accumu lated in the mountain valleys throughout the protracted period of cold. The broken rocks and soil of the highlands were swept into the valleys by torrents of melted ice and snow ; the lower valleys were hollowed out and re-formed under this novel agent ; and the landscape received its present outlines of valley, estuary, and river-beds from the changes wrought in this diluvian epoch. The enormous power of the torrents thus acting continuously throughout a period of prolonged duration, and the vast deposits of sand, gravel, and clay, with the embedded remains of con temporaneous animal and vegetable life with, which they everywhere covered the plains, were viewed till recently solely in relation to the Mosaic narrative of a universal deluge, and were referred implicitly to that source. But recent though the epoch is when compared with oldei geological periods, its antiquity is enormous in relation to historic chronology ; and instead of being the product of a sudden cataclysm of brief duration, it represents pheno mena which required a period of long protracted centuries for their evolution. Within this late tertiary, or quaternary, period are found tie remains of animal life contemporary with primeval ma,ii
and his earliest arts. The very characteristics of some of