Irish deer, the mammoth, mastodon, woolly-haired rhinoceros, and other animals long since extinct, we feel assured that vast changes in physical geography have taken place since their entombment, and are entitled to assign to them a still higher antiquity. In fact we know that all changes in physical conditions, and all removals and extinctions of life, take place by slow and silent stages, and that the greater the difference between the existing and the extinct, the longer must be the time that has elapsed since their extinction. By methods such as these we can establish a scale of old, older, oldest; and there need be no more uncertainty about the results obtained by such methods than there is about the results obtained by the historian in modern, medieval, and ancient history.

Another method by which we arrive at notions of relative antiquity is by the implements and works of art that occur in recent formations, or accompany the remains of man. We know the phases of modern, medieval, Roman, Greek, Egyptian, and Babylonian art, and can assign something like a historical date to such objects and the accumulations in which they occur. We know, too, that man employs tools of wood and stone long before he learns the uses of the metals; and that he reduces the softer metals, and works in copper and bronze, long before he has acquired the mastery over iron and steel. In this way we speak of the ages of stone, bronze, and iron, the one preceding the other, and forming, as it were, a rude scale of time for the antiquarian and geologist. But while one nation may be working in iron, another more belated may be working in bronze, and a third, still more remote and savage, may be adhering to implements of wood and stone. To be of any use, this scale of stone, bronze, and iron, must be applied to the same district; and when so applied, archæologists are now pretty well agreed that it marks with considerable certainty the

various stages of relative antiquity. Of course, were implements of iron ever found along with remains of mammoth and mastodon, the scale would be utterly worthless; but when stone tools invariably accompany the older remains, and those of bronze and iron those of younger and younger date, then we feel assured, from this concordance of the implement scale with that of the animal, that we have hit upon a pretty exact method, so far as Europe at least is concerned; * and it is by both of those modes that man's place in the geological record has been mainly determined.

It will be seen that in speaking of implements of stone, bronze, and iron, the geologist is trenching on the field of archæology, and the archæologist on that of geology. Both must, in fact, lend their aid in solving the question of man's antiquity; and whether it be by sepulchral barrows, by shell-mounds-the old feasting-stations of our northern ancestors-by pile-dwellings in lakes, or by flint implements in river-drifts, much the same kind of reasoning must be employed by both. A lake-dwelling, with implements of stone and bronze, may carry us no further back than the time of the Romans; while a tree-canoe, hollowed out by fire, and found under twelve or fourteen feet of river-silt, may take us thousands of years before Rome had a foundation. The inhabitants of Northern Europe may have lived on shell-fish and been wrapt in skins when the Pharaohs were clothed in fine linen and purple; but when we find

* Some archæologists divide the Stone Period into the palaeolithic and neolithic stages the former the age of rude stone implements, and when man shared the possession of Europe with the mammoth, the cave-bear, the woolly-haired rhinoceros, and other extinct animals; and the latter the age of polished stone implements, and when man began to domesticate the dog, ox, horse, and other existing mammalia. In this way we have four stages of pre-historic time :-1, the Ancient Stone age; 2, the Newer Stone age; 3, the Bronze age; and, 4, the Iron age. For much interesting and well-condensed information on this topic, see Lubbock's "Pre-historic Times,' 1865.

stone implements associated with worked horns of the great Irish elk and reindeer, and with bones of the muskox, mammoth, and woolly-haired rhinoceros, and these in silts and drifts that indicate great physical changes in the geography of Europe, then we may rest assured that these monuments are pre-historic and of unknown antiquity. We have no indication in history that the mammoth, rhinoceros, or Irish deer were inhabitants of Southern and Western Europe; nothing either in history or tradition that points to the time when the reindeer and musk-ox roamed in the latitudes of France and England. It is true that natural events are rarely noticed in ancient history, and especially those of slow and gradual occurrence like the facts of geology; still it may be safely asserted that during the historic period none of the animals above referred to were inhabitants of the southern and western portions of our continent. Whatever the date of these stone implements, and their associated mammoth and rhinoceros remains, they clearly belong to prehistoric times; and the question is thus narrowed to the relative antiquities of certain events which occurred far beyond the reach of the oldest history and the remotest traditions.

In dealing with pre-historic monuments, we may adopt either the methods of the archæologist, who founds chiefly on the comparative rudeness and simplicity of the relics, or those of the geologist, who looks mainly to the superposition of the beds in which the relics occur, or those of the palæontologist, who argues from the specific differences of the flora and fauna; or we may adopt a mixed method, and reason from all that archæology, geology, and palæontology supply. Adopting this latter plan, we reason from the lake-silts, peat-mosses, and deltic deposits containing stone implements and tree-canoes, associated with the bones of extinct varieties of the horse and ox, back to similar depo

sits and cave-earths embedding ruder implements and remains of the Irish deer, reindeer, and musk-ox, and from these again to deeper river-gravels and brick-earths containing implements still simpler in fashion, and associated with the relics of mammoth and rhinoceros. Considerable changes in the physical geography of Europe must have taken place (as these silts and peat-growths imply) since the time of the primitive horse and long-fronted ox; still greater must have taken place since the reindeer and muskox found a suitable climate in the latitude of France and England; and greater still since the mammoth roamed in the pine-forests and over the plains of the same regions. Admitting the changes, the question remains, How shall we estimate the lapse of time required for their fulfilment ? If they are changes of a physical kind, we estimate according to the rate at which similar changes are taking place at the present day; if of a vital kind, by the rate at which extinctions and creations seem to have been effected in former epochs; and if of a kind involving the progress of our own race, we know that civilisation in the long-run is only arrived at, even under the most favourable circumstances, by slow and gradual stages.

Guided by these methods, the pile-dwellings in lakes (the pfahlbauten of Switzerland and the crannoges of Ireland and Scotland*) carry us back to the earlier Celtic times, and may range from two to four thousand years, but clearly they are not of the vast antiquity some archæologists have imagined, and though pre-historic in Europe, may have been contemporary with historical events in Egypt and Western Asia. Estimated by the implement-scale, they belong alike to the ages of iron, bronze, and stone, and mark the long occupancy of South-western Europe by the same partially civilised but gradually improving race. As regards the

* For an account of these Lake-dwellings, see note, p. 257.

shell-mounds (the Kjökken-mödding* of Denmark) and cave-dwellings of Belgium and France, they seem to indicate the presence of a pre-Celtic people, simpler in their mode of life, less civilised, and only acquainted with the use of implements in stone, wood, and bone. Smaller in stature than the Celts, round-headed, hunters and fishers, these pre-Celtic races never seem to have cultivated the soil, or to have settled down in fixed situations. Western Europe appears to have been their home before the Celts left the mountains of the East; and five or six thousand years ago may mark the date of their occupancy of the regions where now are found their shell-mounds, cavedwellings, and kindred reliquiæ. Still earlier than these pre-Celts, Southern Europe to the shores of the Mediterranean, and Western Europe to the limits of the British Islands, seem to have been occupied by a ruder but perhaps kindred race the fashioners of flint implements, and the contemporaries of the reindeer, the mammoth, and woolly rhinoceros. Reindeer, hairy elephants, and woolly-haired rhinoceroses, in the latitudes of France and England, bespeak a severer climate than at present prevails, and under this boreal climate these rude races seem to have earned a scanty subsistence, by hunting and fishing along shore, by lake,

*Literally "kitchen-middens ;" the name given by the Danes to certain mounds which occur along their sea-coasts, and which consist chiefly of the castaway shells of the oyster, cockle, periwinkle, and other edible kinds of shell-fish. These mounds, which have also been found on the shores of Moray and the north of Scotland, are from 3 to 10 feet high, and from 100 to 1000 feet in their longest diameter. They greatly resemble heaps of shells formed by the Red Indians along the eastern shores of the United States, before these tribes were extirpated. The "kitchen-middens" of Europe are ascribed by archæologists to an early people unacquainted with the use of metal, as all the implements found in them are of stone, horn, bone, or wood, with fragments of rude pottery and traces of wood-fires. All the bones yet found are those of wild animals, with the exception perhaps of the dog, which seems to have been domesticated.