The Geological Evidence of The Antiquity of Man

Preliminary Remarks on the Subjects treated of in this Work.

Definition of the Terms Recent and Pleistocene.

Tabular View of the entire Series of Fossiliferous Strata.

No subject has lately excited more curiosity and general interest among geologists and the public than the question of the Antiquity of the Human Race-whether or no we have sufficient evidence in caves, or in the superficial deposits commonly called drift or "diluvium," to prove the former co-existence of man with certain extinct mammalia. For the last half-century the occasional occurrence in various parts of Europe of the bones of Man or the works of his hands in cave-breccias and stalagmites, associated with the remains of the extinct hyaena, bear, elephant, or rhinoceros, has given rise to a suspicion that the date of Man must be carried farther back than we had heretofore imagined. On the other hand extreme reluctance was naturally felt on the part of scientific reasoners to admit the validity of such evidence, seeing that so many caves have been inhabited by a succession of tenants and have been selected by Man as a place not only of domicile, but of sepulture, while some caves have also served as the channels through which the waters of occasional land-floods or engulfed rivers have flowed, so that the remains of living beings which have peopled the district at more than one era may have subsequently been mingled in such caverns and confounded together in one and the same deposit. But the facts brought to light in 1858, during the systematic investigation of the Brixham cave, near Torquay in Devonshire, which will be described in the sequel, excited anew the curiosity of the British public and prepared the way for a general admission that scepticism in regard to the bearing of cave evidence in favour of the antiquity of Man had previously been pushed to an extreme.

Since that period many of the facts formerly adduced in favour of the co-existence in ancient times of Man with certain species of mammalia long since extinct have been re-examined in England and on the Continent, and new cases bearing on the same question, whether relating to caves or to alluvial strata in valleys, have been brought to light. To qualify myself for the appreciation and discussion of these cases, I have visited in the course of the last three years many parts of England, France, and Belgium, and have communicated personally or by letter with not a few of the geologists, English and foreign, who have taken part in these researches. Besides explaining in the present volume the results of this inquiry, I shall give a description of the glacial formations of Europe and North America, that I may allude to the theories entertained respecting their origin, and consider their probable relations in a chronological point of view to the human epoch, and why throughout a great part of the northern hemisphere they so often interpose an abrupt barrier to all attempts to trace farther back into the past the signs of the existence of Man upon the earth.

In the concluding chapters I shall offer a few remarks on the recent modifications of the Lamarckian theory of progressive development and transmutation, which are suggested by Mr. Darwin's work on the "Origin of Species by Variation and Natural Selection," and the bearing of this hypothesis on the different races of mankind and their connection with other parts of the animal kingdom.

NOMENCLATURE.

Some preliminary explanation of the nomenclature adopted in the following pages will be indispensable, that the meaning attached to the terms Recent, Pleistocene, and Post-Tertiary may be correctly understood. [Note 1]

Previously to the year 1833, when I published the third volume of the "Principles of Geology," the strata called Tertiary had been divided by geologists into Lower, Middle, and Upper; the Lower comprising the oldest formations of the environs of Paris and London, with others of like age; the Middle, those of Bordeaux and Touraine; and the Upper, all that lay above or were newer than the last-mentioned group.

When engaged in 1828 in preparing for the press the treatise on geology above alluded to, I conceived the idea of classing the whole of this series of strata according to the different degrees of affinity which their fossil testacea bore to the living fauna. Having obtained information on this subject during my travels on the Continent, I learnt that M. Deshayes of Paris, already celebrated as a conchologist, had been led independently by the study of a large collection of Recent and fossil shells to very similar views respecting the possibility of arranging the Tertiary formations in chronological order, according to the proportional number of species of shells identical with living ones, which characterised each of the successive groups above mentioned. After comparing 3000 fossil species with 5000 living ones, the result arrived at was, that in the lower Tertiary strata there were about 3 1/2 per cent identical with Recent; in the middle Tertiary (the faluns of the Loire and Gironde), about 17 per cent; and in the upper tertiary, from 35 to 50, and sometimes in the most modern beds as much as 90 to 95 per cent.

For the sake of clearness and brevity, I proposed to give short technical names to these sets of strata, or the periods to which they respectively belonged. I called the first or oldest of them Eocene, the second Miocene, and the third Pliocene. The first of the above terms, Eocene, is derived from Greek eos, dawn, and Greek kainos, recent; because an extremely small proportion of the fossil shells of this period could be referred to living species, so that this era seemed to indicate the dawn of the present testaceous fauna, no living species of shells having been detected in the antecedent or Secondary rocks.

Some conchologists are now unwilling to allow that any Eocene species of shell has really survived to our times so unaltered as to allow of its specific identification with a living species. I cannot enter in this place into this wide controversy. It is enough at present to remark that the character of the Eocene fauna, as contrasted with that of the antecedent Secondary formations, wears a very modern aspect, and that some able living conchologists still maintain that there are Eocene shells not specifically distinguishable from those now extant; though they may be fewer in number than was supposed in 1833.

The term Miocene (from Greek meion, less; and Greek kainos, recent) is intended to express a minor proportion of Recent species (of testacea); the term Pliocene (from Greek pleion, more; and Greek kainos, recent), a comparative plurality of the same.

It has sometimes been objected to this nomenclature that certain species of infusoria found in the chalk are still existing, and, on the other hand, the Miocene and Older Pliocene deposits often contain the remains of mammalia, reptiles, and fish, exclusively of extinct species. But the reader must bear in mind that the terms Eocene, Miocene, and Pliocene were originally invented with reference purely to conchological data, and in that sense have always been and are still used by me.

Since the first introduction of the terms above defined, the number of new living species of shells obtained from different parts of the globe has been exceedingly great, supplying fresh data for comparison, and enabling the palaeontologist to correct many erroneous identifications of fossil and Recent forms. New species also have been collected in abundance from Tertiary formations of every age, while newly discovered groups of strata have filled up gaps in the previously known series. Hence modifications and reforms have been called for in the classifications first proposed. The Eocene, Miocene, and Pliocene periods have been made to comprehend certain sets of strata of which the fossils do not always conform strictly in the proportion of Recent to extinct species with the definitions first given by me, or which are implied in the etymology of those terms. These innovations have been treated of in my "Elements or Manual of Elementary Geology," and in the Supplement to the fifth edition of the same, published in 1859, where some modifications of my classification, as first proposed, are introduced; but I need not dwell on these on the present occasion, as the only formations with which we shall be concerned in the present volume are those of the most modern date, or the Post-Tertiary. It will be convenient to divide these into two groups, the Recent and the Pleistocene. In the Recent we may comprehend those deposits in which not only all the shells but all the fossil mammalia are of living species; in the Pleistocene those strata in which, the shells being Recent, a portion, and often a considerable one, of the accompanying fossil quadrupeds belongs to extinct species.

Cases will occur where it may be scarcely possible to draw the line of demarcation between the Newer Pliocene and Pleistocene, or between the latter and the recent deposits; and we must expect these difficulties to increase rather than diminish with every advance in our knowledge, and in proportion as gaps are filled up in the series of geological records.

The annexed tabular view (Table 1/1) of the whole series of fossiliferous strata will enable the reader to see at a glance the chronological relation of the Recent and Pleistocene to the antecedent periods. [Note 2]

TABLE 1/1. STRATIFIED ROCKS.

KAINOZOIC OR TERTIARY: Pleistocene and Recent. Pliocene.

Miocene.

Oligocene.

Eocene.

MESOZOIC OR SECONDARY: Cretaceous. Jurassic.

Triassic.

PALAEOZOIC OR PRIMARY: Permian. Carboniferous.

Devonian or old Red Sandstone.

Silurian.

Ordovician.

Cambrian.

PRECAMBRIAN OR ARCHAEAN.

LAKE-DWELLINGS.

(Restored by Dr. F. Keller, partly from Dumont D'Urville's

Sketch of similar habitations in New Guinea.)

Works of Art in Danish Peat-Mosses.

Remains of three Periods of Vegetation in the Peat.

Ages of Stone, Bronze, and Iron.

Shell-Mounds or ancient Refuse-Heaps of the Danish Islands.

Change in geographical Distribution of Marine Mollusca

since their Origin.

Embedded Remains of Mammalia of Recent Species.

Human Skulls of the same Period.

Swiss Lake-Dwellings built on Piles.

Stone and Bronze Implements found in them.

Fossil Cereals and other Plants.

Remains of Mammalia, wild and domesticated.

No extinct Species.

Chronological Computations of the Date of the Bronze and

Stone Periods in Switzerland.

Lake-Dwellings, or artificial Islands called "Crannoges,"

in Ireland.

WORKS OF ART IN DANISH PEAT.

When treating in the "Principles of Geology" of the changes of the earth which have taken place in comparatively modern times, I have spoken of the embedding of organic bodies and human remains in peat, and explained under what conditions the growth of that vegetable substance is going on in northern and humid climates. Of late years, since I first alluded to the subject, more extensive investigations have been made into the history of the Danish peat-mosses. Of the results of these inquiries I shall give a brief abstract in the present chapter, that we may afterwards compare them with deposits of older date, which throw light on the antiquity of the human race.

The deposits of peat in Denmark,* varying in depth from 10 to 30 feet, have been formed in hollows or depressions in the northern drift or boulder formation hereafter to be described. (* An excellent account of these researches of Danish naturalists and antiquaries has been drawn up by an able Swiss geologist, M.A. Morlot, and will be found in the "Bulletin de la Societe Vaudoise des Sci. Nat." tome 6 Lausanne 1860.) The lowest stratum, 2 to 3 feet thick, consists of swamp-peat composed chiefly of moss or sphagnum, above which lies another growth of peat, not made up exclusively of aquatic or swamp plants. Around the borders of the bogs, and at various depths in them, lie trunks of trees, especially of the Scotch fir (Pinus sylvestris), often 3 feet in diameter, which must have grown on the margin of the peat-mosses, and have frequently fallen into them. This tree is not now, nor has ever been in historical times, a native of the Danish Islands, and when introduced there has not thriven; yet it was evidently indigenous in the human period, for Steenstrup has taken out with his own hands a flint instrument from below a buried trunk of one of these pines. It appears clear that the same Scotch fir was afterwards supplanted by the sessile variety of the common oak, of which many prostrate trunks occur in the peat at higher levels than the pines; and still higher the pedunculated variety of the same oak (Quercus robur, L.) occurs with the alder, birch (Betula verrucosa, Ehrh.), and hazel. The oak has now in its turn been almost superseded in Denmark by the common beech. Other trees, such as the white birch (Betula alba), characterise the lower part of the bogs, and disappear from the higher; while others again, like the aspen (Populus tremula), occur at all levels, and still flourish in Denmark. All the land and freshwater shells, and all the mammalia as well as the plants, whose remains occur buried in the Danish peat, are of Recent species. [Note 3]

It has been stated, that a stone implement was found under a buried Scotch fir at a great depth in the peat. By collecting and studying a vast variety of such implements, and other articles of human workmanship preserved in peat and in sand-dunes on the coast, as also in certain shell-mounds of the aborigines presently to be described, the Danish and Swedish antiquaries and naturalists, MM. Nilsson, Steenstrup, Forchhammer, Thomsen, Worsaae, and others, have succeeded in establishing a chronological succession of periods, which they have called the ages of stone, of bronze, and of iron, named from the materials which have each in their turn served for the fabrication of implements.

The age of stone in Denmark coincided with the period of the first vegetation, or that of the Scotch fir, and in part at least with the second vegetation, or that of the oak. But a considerable portion of the oak epoch coincided with "the age of bronze," for swords and shields of that metal, now in the Museum of Copenhagen, have been taken out of peat in which oaks abound. The age of iron corresponded more nearly with that of the beech tree.*

(* Morlot "Bulletin de la Societe Vaudoise des Sci. Nat."

tome 6 page 292.) [Note 4]

M. Morlot, to whom we are indebted for a masterly sketch of the recent progress of this new line of research, followed up with so much success in Scandinavia and Switzerland, observes that the introduction of the first tools made of bronze among a people previously ignorant of the use of metals, implies a great advance in the arts, for bronze is an alloy of about nine parts of copper and one of tin; and although the former metal, copper, is by no means rare, and is occasionally found pure or in a native state, tin is not only scarce but never occurs native. To detect the existence of this metal in its ore, then to disengage it from the matrix, and finally, after blending it in due proportion with copper, to cast the fused mixture in a mould, allowing time for it to acquire hardness by slow cooling, all this bespeaks no small sagacity and skilful manipulation. Accordingly, the pottery found associated with weapons of bronze is of a more ornamental and tasteful style than any which belongs to the age of stone. Some of the moulds in which the bronze instruments were cast, and "tags," as they are called, of bronze, which are formed in the hole through which the fused metal was poured, have been found. The number and variety of objects belonging to the age of bronze indicates its long duration, as does the progress in the arts implied by the rudeness of the earlier tools, often mere repetitions of those of the stone age, as contrasted with the more skilfully worked weapons of a later stage of the same period.

It has been suggested that an age of copper must always have intervened between that of stone and bronze; but if so, the interval seems to have been short in Europe, owing apparently to the territory occupied by the aboriginal inhabitants having been invaded and conquered by a people coming from the East, to whom the use of swords, spears, and other weapons of bronze was familiar. Hatchets, however, of copper have been found in the Danish peat.

The next stage of improvement, or that manifested by the substitution of iron for bronze, indicates another stride in the progress of the arts. Iron never presents itself, except in meteorites, in a native state, so that to recognise its ores, and then to separate the metal from its matrix, demands no inconsiderable exercise of the powers of observation and invention. To fuse the ore requires an intense heat, not to be obtained without artificial appliances, such as pipes inflated by the human breath, or bellows, or some other suitable machinery.

DANISH SHELL-MOUNDS, OR KJOKKENMODDING.*

(* Mr. John Lubbock published, after these sheets were

written, an able paper on the Danish "Shell-mounds" in the

October number of the "Natural History Review" 1861 page

489, in which he has described the results of a recent visit

to Denmark, made by him in company with Mr. Busk.)

In addition to the peat-mosses, another class of memorials found in Denmark has thrown light on the pre-historical age. At certain points along the shores of nearly all the Danish islands, mounds may be seen, consisting chiefly of thousands of cast-away shells of the oyster, cockle, and other molluscs of the same species as those which are now eaten by Man. These shells are plentifully mixed up with the bones of various quadrupeds, birds, and fish, which served as the food of the rude hunters and fishers by whom the mounds were accumulated. I have seen similar large heaps of oysters, and other marine shells with interspersed stone implements, near the seashore, both in Massachusetts and in Georgia, U.S.A., left by the native North American Indians at points near to which they were in the habit of pitching their wigwams for centuries before the white man arrived.

Such accumulations are called by the Danes, Kjokkenmodding, or "kitchen-middens." Scattered all through them are flint knives, hatchets, and other instruments of stone, horn, wood, and bone, with fragments of coarse pottery, mixed with charcoal and cinders, but never any implements of bronze, still less of iron. The stone hatchets and knives had been sharpened by rubbing, and in this respect are one degree less rude than those of an older date, associated in France with the bones of extinct mammalia, of which more in the sequel. The mounds vary in height from 3 to 10 feet, and in area are some of them 1000 feet long, and from 150 to 200 wide. They are rarely placed more than 10 feet above the level of the sea, and are confined to its immediate neighbourhood, or if not (and there are cases where they are several miles from the shore), the distance is ascribable to the entrance of a small stream, which has deposited sediment, or to the growth of a peaty swamp, by which the land has been made to advance on the Baltic, as it is still doing in many places, aided, according to Puggaard, by a very slow upheaval of the whole country at the rate of 2 or 3 inches in a century.

There is also another geographical fact equally in favour of the antiquity of the mounds, namely, that they are wanting on those parts of the coast which border the Western Ocean, or exactly where the waves are now slowly eating away the land. There is every reason to presume that originally there were stations along the coast of the North Sea as well as that of the Baltic, but by the gradual undermining of the cliffs they have all been swept away.

Another striking proof, perhaps the most conclusive of all, that the "kitchen-middens" are very old, is derived from the character of their embedded shells. These consist entirely of living species; but, in the first place, the common eatable oyster is among them, attaining its full size, whereas the same Ostrea edulis cannot live at present in the brackish waters of the Baltic except near its entrance, where, whenever a north-westerly gale prevails, a current setting in from the ocean pours in a great body of salt water. Yet it seems that during the whole time of the accumulation of the "kitchen-middens" the oyster flourished in places from which it is now excluded. In like manner the eatable cockle, mussel, and periwinkle (Cardium edule, Mytilus edulis, and Littorina littorea), which are met with in great numbers in the "middens," are of the ordinary dimensions which they acquire in the ocean, whereas the same species now living in the adjoining parts of the Baltic only attain a third of their natural size, being stunted and dwarfed in their growth by the quantity of fresh water poured by rivers into that inland sea.*

(* See "Principles of Geology" chapter 30.)

Hence we may confidently infer that in the days of the aboriginal hunters and fishers, the ocean had freer access than now to the Baltic, communicating probably through the peninsula of Jutland, Jutland having been at no remote period an archipelago. Even in the course of the nineteenth century, the salt waters have made one irruption into the Baltic by the Lymfiord, although they have been now again excluded. It is also affirmed that other channels were open in historical times which are now silted up.*

(* See Morlot "Bulletin de la Societe Vaudoise des Sci.

Nat." tome 6.)

If we next turn to the remains of vertebrata preserved in the mounds, we find that here also, as in the Danish peat-mosses, all the quadrupeds belong to species known to have inhabited Europe within the memory of Man. No remains of the mammoth, or rhinoceros, or of any extinct species appear, except those of the wild bull (Bos urus, Linn., or Bos primigenius, Bojanus), which are in such numbers as to prove that the species was a favourite food of the ancient people. But as this animal was seen by Julius Caesar, and survived long after his time, its presence alone would not go far to prove the mounds to be of high antiquity. The Lithuanian aurochs or bison (Bos bison, L., Bos priscus, Boj.), which has escaped extirpation only because protected by the Russian Czars, surviving in one forest in Lithuania) has not yet been met with, but will no doubt be detected hereafter, as it has been already found in the Danish peat. The beaver, long since destroyed in Denmark, occurs frequently, as does the seal (Phoca Gryppus, Fab.), now very rare on the Danish coast. With these are mingled bones of the red deer and roe, but the reindeer has not yet been found. There are also the bones of many carnivora, such as the lynx, fox, and wolf, but no signs of any domesticated animals except the dog. The long bones of the larger mammalia have been all broken as if by some instrument, in such a manner as to allow of the extraction of the marrow, and the gristly parts have been gnawed off, as if by dogs, to whose agency is also attributed the almost entire absence of the bones of young birds and of the smaller bones and softer parts of the skeletons of birds in general, even of those of large size. In reference to the latter, it has been proved experimentally by Professor Steenstrup, that if the same species of birds are now given to dogs, they will devour those parts of the skeleton which are missing, and leave just those which are preserved in the old "kitchen-middens."

The dogs of the mounds, the only domesticated animals, are of a smaller race than those of the bronze period, as shown by the peat-mosses, and the dogs of the bronze age are inferior in size and strength to those of the iron age. The domestic ox, horse, and sheep, which are wanting in the mounds, are confined to that part of the Danish peat which was formed in the ages of bronze and iron.

Among the bones of birds, scarcely any are more frequent in the mounds than those of the auk (Alca impennis), now extinct. The Capercailzie (Tetrao urogallus) is also met with, and may, it is suggested, have fed on the buds of the Scotch fir in times when that tree flourished around the peat-bogs. The different stages of growth of the roedeer's horns, and the presence of the wild swan, now only a winter visitor, have been appealed to as proving that the aborigines resided in the same settlements all the year round. That they also ventured out to sea in canoes such as are now found in the peat-mosses, hollowed out of the trunk of a single tree, to catch fish far from land, is testified by the bony relics of several deep-sea species, such as the herring, cod, and flounder. The ancient people were not cannibals, for no human bones are mingled with the spoils of the chase. Skulls, however, have been obtained not only from peat, but from tumuli of the stone period believed to be contemporaneous with the mounds. These skulls are small and round, and have a prominent ridge over the orbits of the eyes, showing that the ancient race was of small stature, with round heads and overhanging eyebrows-in short, they bore a considerable resemblance to the modern Laplanders. The human skulls of the bronze age found in the Danish peat, and those of the iron period, are of an elongated form and larger size. There appear to be very few well-authenticated examples of crania referable to the bronze period-a circumstance no doubt attributable to the custom prevalent among the people of that era of burning their dead and collecting their bones in funeral urns.

No traces of grain of any sort have hitherto been discovered, nor any other indication that the ancient people had any knowledge of agriculture. The only vegetable remains in the mounds are burnt pieces of wood and some charred substance referred by Dr. Forchhammer to the Zostera marina, a sea plant which was perhaps used in the production of salt.

What may be the antiquity of the earliest human remains preserved in the Danish peat cannot be estimated in centuries with any approach to accuracy. In the first place, in going back to the bronze age, we already find ourselves beyond the reach of history or even of tradition. In the time of the Romans the Danish Isles were covered, as now, with magnificent beech forests. Nowhere in the world does this tree flourish more luxuriantly than in Denmark, and eighteen centuries seem to have done little or nothing towards modifying the character of the forest vegetation. Yet in the antecedent bronze period there were no beech trees, or at most but a few stragglers, the country being then covered with oak. In the age of stone again, the Scotch fir prevailed, and already there were human inhabitants in those old pine forests. How many generations of each species of tree flourished in succession before the pine was supplanted by the oak, and the oak by the beech, can be but vaguely conjectured, but the minimum of time required for the formation of so much peat must, according to the estimate of Steenstrup and other good authorities, have amounted to at least 4000 years; and there is nothing in the observed rate of the growth of peat opposed to the conclusion that the number of centuries may not have been four times as great, even though the signs of Man's existence have not yet been traced down to the lowest or amorphous stratum. As to the "kitchen-middens," they correspond in date to the older portion of the peaty record, or to the earliest part of the age of stone as known in Denmark.

ANCIENT SWISS LAKE-DWELLINGS, BUILT ON PILES.

In the shallow parts of many Swiss lakes, where there is a depth of no more than from 5 to 15 feet of water, ancient wooden piles are observed at the bottom sometimes worn down to the surface of the mud, sometimes projecting slightly above it. These have evidently once supported villages, nearly all of them of unknown date, but the most ancient of which certainly belonged to the age of stone, for hundreds of implements resembling those of the Danish shell-mounds and peat-mosses have been dredged up from the mud into which the piles were driven.

The earliest historical account of such habitations is that given by Herodotus of a Thracian tribe, who dwelt, in the year 520 B.C., in Prasias, a small mountain-lake of Paeonia, now part of modern Roumelia.*

(* Herodotus lib. 5 cap. 16. Rediscovered by M. de Ville

"Natural History Review" volume 2 1862 page 486.)

Their habitations were constructed on platforms raised above the lake, and resting on piles. They were connected with the shore by a narrow causeway of similar formation. Such platforms must have been of considerable extent, for the Paeonians lived there with their families and horses. Their food consisted largely of the fish which the lake produced in abundance.

In rude and unsettled times, such insular sites afforded safe retreats, all communication with the mainland being cut off, except by boats, or by such wooden bridges as could be easily removed.

The Swiss lake-dwellings seem first to have attracted attention during the dry winter of 1853-54, when the lakes and rivers sank lower than had ever been previously known, and when the inhabitants of Meilen, on the Lake of Zurich, resolved to raise the level of some ground and turn it into land, by throwing mud upon it obtained by dredging in the adjoining shallow water. During these dredging operations they discovered a number of wooden piles deeply driven into the bed of the lake, and among them a great many hammers, axes, celts, and other instruments. All these belonged to the stone period with two exceptions, namely, an armlet of thin brass wire, and a small bronze hatchet.

Fragments of rude pottery fashioned by the hand were abundant, also masses of charred wood, supposed to have formed parts of the platform on which the wooden cabins were built. Of this burnt timber, on this and other sites, subsequently explored, there was such an abundance as to lead to the conclusion that many of the settlements must have perished by fire. Herodotus has recorded that the Paeonians, above alluded to, preserved their independence during the Persian invasion, and defied the attacks of Darius by aid of the peculiar position of their dwellings. "But their safety," observes Mr. Wylie,* "was probably owing to their living in the middle of the lake, (Greek) en mese te limne, whereas the ancient Swiss settlers were compelled by the rapidly increasing depth of the water near the margins of their lakes to construct their habitations at a short distance from the shore, within easy bowshot of the land, and therefore not out of reach of fiery projectiles, against which thatched roofs and wooden walls could present but a poor defence."

(* W.M. Wylie "Archaeologia" volume 38 1859, a valuable

paper on the Swiss and Irish lake-habitations.)

To these circumstances and to accidental fires we are probably indebted for the frequent preservation, in the mud around the site of the old settlements, of the most precious tools and works of art, such as would never have been thrown into the Danish "kitchen-middens," which have been aptly compared to a modern dusthole.

Dr. Ferdinand Keller of Zurich has drawn up a series of most instructive memoirs, illustrated with well-executed plates, of the treasures in stone, bronze, and bone brought to light in these subaqueous repositories, and has given an ideal restoration of part of one of the old villages (see Plate 1 above),* such as he conceives may have existed on the lakes of Zurich and Bienne.

(*Keller "Pfahlbauten, Antiquarische Gesellschaft in Zurich"

Bd. 12 and 13 1858-1861. In the fifth number of the "Natural

History Review" January 9, 1862, Mr. Lubbock has published

an excellent account of the works of the Swiss writers on

their lake-habitations.)

In this view, however, he has not simply trusted to his imagination, but has availed himself of a sketch published by M. Dumont d'Urville, of similar habitations of the Papuans in New Guinea in the Bay of Dorei. It is also stated by Dr. Keller, that on the River Limmat, near Zurich, so late as the last century, there were several fishing-huts constructed on this same plan.*

(* Keller "Pfahlbauten, Antiquarische Gesellschaft in

Zurich" Bd. 9 page 81 note.)

It will be remarked that one of the cabins is represented as circular. That such was the form of many in Switzerland is inferred from the shape of pieces of clay which lined the interior, and which owe their preservation apparently to their having been hardened by fire when the village was burnt. In the sketch (Plate 1), some fishing-nets are seen spread out to dry on the wooden platform. The Swiss archaeologist has found abundant evidence of fishing-gear, consisting of pieces of cord, hooks, and stones used as weights. A canoe also is introduced, such as are occasionally met with. One of these, made of the trunk of a single tree, fifty feet long and three and a half feet wide, was found capsized at the bottom of the Lake of Bienne. It appears to have been laden with stones, such as were used to raise the foundation of some of the artificial islands.

It is believed that as many as 300 wooden huts were sometimes comprised in one settlement, and that they may have contained about 1000 inhabitants. At Wangen, M. Lohle has calculated that 40,000 piles were used, probably not all planted at one time nor by one generation. Among the works of great merit devoted specially to a description of the Swiss lake-habitations is that of M. Troyon, published in 1860.*

(* "Sur les Habitations lacustres.")

The number of sites which he and other authors have already enumerated in Switzerland is truly wonderful. They occur on the large lakes of Constance, Zurich, Geneva, and Neufchatel, and on most of the smaller ones. Some are exclusively of the stone age, others of the bronze period. Of these last more than twenty are spoken of on the Lake of Geneva alone, more than forty on that of Neufchatel, and twenty on the small Lake of Bienne.

One of the sites first studied by the Swiss antiquaries was the small lake of Moosseedorf, near Berne, where implements of stone, horn, and bone, but none of metal, were obtained. Although the flint here employed must have come from a distance (probably from the south of France), the chippings of the material are in such profusion as to imply that there was a manufactory of implements on the spot. Here also, as in several other settlements, hatchets and wedges of jade have been observed of a kind said not to occur in Switzerland or the adjoining parts of Europe, and which some mineralogists would fain derive from the East; amber also, which, it is supposed, was imported from the shores of the Baltic.

At Wangen near Stein, on the Lake of Constance, another of the most ancient of the lake-dwellings, hatchets of serpentine and greenstone, and arrow-heads of quartz have been met with. Here also remains of a kind of cloth, supposed to be of flax, not woven but plaited, have been detected. Professor Heer has recognised lumps of carbonised wheat, Triticum vulgare, and grains of another kind, T. dicoccum, and barley, Hordeum distichum, and flat round cakes of bread; and at Robbenhausen and elsewhere Hordeum hexastichum in fine ears, the same kind of barley which is found associated with Egyptian mummies, showing clearly that in the stone period the lake-dwellers cultivated all these cereals, besides having domesticated the dog, the ox, the sheep, and the goat.

Carbonised apples and pears of small size, such as still grow in the Swiss forests, stones of the wild plum, seeds of the raspberry and blackberry, and beech-nuts, also occur in the mud, and hazel-nuts in great plenty.

Near Morges, on the Lake of Geneva, a settlement of the bronze period, no less than forty hatchets of that metal have been dredged up, and in many other localities the number and variety of weapons and utensils discovered, in a fine state of preservation, is truly astonishing.

It is remarkable that as yet all the settlements of the bronze period are confined to Western and Central Switzerland. In the more eastern lakes those of the stone period alone have as yet been discovered.

The tools, ornaments, and pottery of the bronze period in Switzerland bear a close resemblance to those of corresponding age in Denmark, attesting the wide spread of a uniform civilisation over Central Europe at that era. In some few of the Swiss aquatic stations a mixture of bronze and iron implements has been observed, but no coins. At Tiefenau, near Berne, in ground supposed to have been a battle-field, coins and medals of bronze and silver, struck at Marseilles, and of Greek manufacture, and iron swords, have been found, all belonging to the first and pre-Roman division of the age of iron.

In the settlements of the bronze era the wooden piles are not so much decayed as those of the stone period; the latter having wasted down quite to the level of the mud, whereas the piles of the bronze age (as in the Lake of Bienne, for example) still project above it.

Professor Rutimeyer of Basle, well-known to palaeontologists as the author of several important memoirs on fossil vertebrata, has recently published a scientific description of great interest of the animal remains dredged up at various stations where they had been embedded for ages in the mud into which the piles were driven.*

(* "Die Fauna der Pfahlbauten in der Schweiz" Basel 1861.)

These bones bear the same relation to the primitive inhabitants of Switzerland and some of their immediate successors as do the contents of the Danish "kitchen-middens" to the ancient fishing and hunting tribes who lived on the shores of the Baltic.

The list of wild mammalia enumerated in this excellent treatise contains no less than twenty-four species, exclusive of several domesticated ones: besides which there are eighteen species of birds, the wild swan, goose, and two species of ducks being among them; also three reptiles, including the eatable frog and freshwater tortoise; and lastly, nine species of freshwater fish. All these (amounting to fifty-four species) are with one exception still living in Europe. The exception is the wild bull (Bos primigenius), which, as before stated, survived in historical times. The following are the mammalia alluded to:-The bear (Ursus arctos), the badger, the common marten, the polecat, the ermine, the weasel, the otter, wolf, fox, wild cat, hedgehog, squirrel, field-mouse (Mus sylvaticus), hare, beaver, hog (comprising two races, namely, the wild boar and swamp-hog), the stag (Cervus elaphus), the roe-deer, the fallow-deer, the elk, the steinbock (Capra ibex), the chamois, the Lithuanian bison, and the wild bull. The domesticated species comprise the dog, horse, ass, pig, goat, sheep, and several bovine races.

The greater number, if not all, of these animals served for food, and all the bones which contained marrow have been split open in the same way as the corresponding ones found in the shell-mounds of Denmark before mentioned. The bones both of the wild bull and the bison are invariably split in this manner. As a rule, the lower jaws with teeth occur in greater abundance than any other parts of the skeleton-a circumstance which, geologists know, holds good in regard to fossil mammalia of all periods. As yet the reindeer is missing in the Swiss lake-settlements as in the Danish "kitchen-middens," although this animal in more ancient times ranged over France, together with the mammoth, as far south as the Pyrenees.

A careful comparison of the bones from different sites has shown that in settlements such as Wangen and Moosseedorf, belonging to the earliest age of stone, when the habits of the hunter state predominated over those of the pastoral, venison, or the flesh of the stag and roe, was more eaten than the flesh of the domestic cattle and sheep. This was afterwards reversed in the later stone period and in the age of bronze. At that later period also the tame pig, which is wanting in some of the oldest stations, had replaced the wild boar as a common article of food. In the beginning of the age of stone, in Switzerland, the goats outnumbered the sheep, but towards the close of the same period the sheep were more abundant than the goats.

The fox in the first era was very common, but it nearly disappears in the bronze age, during which period a large hunting-dog, supposed to have been imported into Switzerland from some foreign country, becomes the chief representative of the canine genus.

A single fragment of the bone of a hare (Lepus timidus) has been found at Moosseedorf. The almost universal absence of this quadruped is supposed to imply that the Swiss lake-dwellers were prevented from eating that animal by the same superstition which now prevails among the Laplanders, and which Julius Caesar found in full force amongst the ancient Britons.*

(* "Commentaries" lib 5 chapter 12.)

That the lake-dwellers should have fed so largely on the fox, while they abstained from touching the hare, establishes, says Rutimeyer, a singular contrast between their tastes and ours.

Even in the earliest settlements, as already hinted, several domesticated animals occur, namely, the ox, sheep, goat, and dog. Of the three last, each was represented by one race only; but there were two races of cattle, the most common being of small size, and called by Rutimeyer Bos brachyceros (Bos longifrons, Owen), or the marsh cow, the other derived from the wild bull; though, as no skull has yet been discovered, this identification is not so certain as could be wished. It is, however, beyond question that at a later era, namely, towards the close of the stone and beginning of the bronze period, the lake-dwellers had succeeded in taming that formidable brute the Bos primigenius, the Urus of Caesar, which he described as very fierce, swift, and strong, and scarcely inferior to the elephant in size. In a tame state its bones were somewhat less massive and heavy, and its horns were somewhat smaller than in wild individuals. Still in its domesticated form, it rivalled in dimensions the largest living cattle, those of Friesland, in North Holland, for example. When most abundant, as at Concise on the Lake of Neufchatel, it had nearly superseded the smaller race, Bos brachyceros, and was accompanied there for a short time by a third bovine variety, called Bos trochoceros, an Italian race, supposed to have been imported from the southern side of the Alps. (Caesar "Commentaries" lib 5 chapter 12.) This last-mentioned race, however, seems only to have lasted for a short time in Switzerland.

The wild bull (Bos primigenius) is supposed to have flourished for a while in a wild and tame state, just as now in Europe the domestic pig co-exists with the wild boar; and Rutimeyer agrees with Cuvier and Bell,* in considering our larger domestic cattle of northern Europe as the descendants of this wild bull, an opinion which Owen disputes.**

(* "British Quadrupeds" page 415.)

(** "British Fossil Mammal." page 500.)

In the later division of the stone period, there were two tame races of the pig, according to Rutimeyer; one large, and derived from the wild boar, the other smaller, called the "marsh-hog," or Sus scrofa palustris. It may be asked how the osteologist can distinguish the tame from the wild races of the same species by their skeletons alone. Among other characters, the diminished thickness of the bones and the comparative smallness of the ridges, which afford attachment to the muscles, are relied on; also the smaller dimensions of the tusks in the boar, and of the whole jaw and skull; and, in like manner, the diminished size of the horns of the bull and other modifications, which are the effects of a regular supply of food, and the absence of all necessity of exerting their activity and strength to obtain subsistence and defend themselves against their enemies.

A middle-sized race of dogs continued unaltered throughout the whole of the stone period; but the people of the bronze age possessed a larger hunting-dog, and with it a small horse, of which genus very few traces have been detected in the earlier settlements-a single tooth, for example, at Wangen, and only one or two bones at two or three other places.

In passing from the oldest to the most modern sites, the extirpation of the elk and beaver, and the gradual reduction in numbers of the bear, stag, roe, and freshwater tortoise are distinctly perceptible. The aurochs, or Lithuanian bison, appears to have died out in Switzerland about the time when weapons of bronze came into use. It is only in a few of the most modern lake-dwellings, such as Noville and Chavannes in the Canton de Vaud (which the antiquaries refer to the sixth century), that some traces are observable of the domestic cat, as well as of a sheep with crooked horns and with them bones of the domestic fowl.

After the sixth century, no extinction of any wild quadruped nor introduction of any tame one appears to have taken place, but the fauna was still modified by the wild species continuing to diminish in number and the tame ones to become more diversified by breeding and crossing, especially in the case of the dog, horse, and sheep. On the whole, however, the divergence of the domestic races from their aboriginal wild types, as exemplified at Wangen and Moosseedorf, is confined, according to Professor Rutimeyer, within narrow limits. As to the goat, it has remained nearly constant and true to its pristine form, and the small race of goat-horned sheep still lingers in some alpine valleys in the Upper Rhine; and in the same region a race of pigs, corresponding to the domesticated variety of Sus scrofa palustris, may still be seen.

Amidst all this profusion of animal remains extremely few bones of Man have been discovered; and only one skull, dredged up from Meilen, on the Lake of Zurich, of the early stone period, seems as yet to have been carefully examined. Respecting this specimen, Professor His observes that it exhibits, instead of the small and rounded form proper to the Danish peat-mosses, a type much more like that now prevailing in Switzerland, which is intermediate between the long-headed and short-headed form. (Rutimeyer "Die Fauna der Pfahlbauten in der Schweiz" page 181.)

So far, therefore, as we can draw safe conclusions from a single specimen, there has been no marked change of race in the human population of Switzerland during the periods above considered.

It is still a question whether any of these subaqueous repositories of ancient relics in Switzerland go back so far in time as the kitchen-middens of Denmark, for in these last there are no domesticated animals except the dog, and no signs of the cultivation of wheat or barley; whereas we have seen that, in one of the oldest of the Swiss settlements, at Wangen, no less than three cereals make their appearance, with four kinds of domestic animals. Yet there is no small risk of error in speculating on the relative claims to antiquity of such ancient tribes, for some of them may have remained isolated for ages and stationary in their habits, while others advanced and improved.

We know that nations, both before and after the introduction of metals, may continue in very different stages of civilisation, even after commercial intercourse has been established between them, and where they are separated by a less distance than that which divides the Alps from the Baltic.

The attempts of the Swiss geologists and archaeologists to estimate definitely in years the antiquity of the bronze and stone periods, although as yet confessedly imperfect, deserve notice, and appear to me to be full of promise. The most elaborate calculation is that made by M. Morlot, respecting the delta of the Tiniere, a torrent which flows into the Lake of Geneva near Villeneuve. This small delta, to which the stream is annually making additions, is composed of gravel and sand. Its shape is that of a flattened cone, and its internal structure has of late been laid open to view in a railway cutting 1000 feet long and 32 feet deep. The regularity of its structure throughout implies that it has been formed very gradually, and by the uniform action of the same causes. Three layers of vegetable soil, each of which must at one time have formed the surface of the cone, have been cut through at different depths. The first of these was traced over a surface of 15,000 square feet, having an average thickness of 5 inches, and being about 4 feet below the present surface of the cone. This upper layer belonged to the Roman period, and contained Roman tiles and a coin. The second layer, followed over a surface of 25,000 square feet, was 6 inches thick, and lay at a depth of 10 feet. In it were found fragments of unvarnished pottery and a pair of tweezers in bronze, indicating the bronze epoch. The third layer, followed for 35,000 square feet, was 6 or 7 inches thick and 19 feet deep. In it were fragments of rude pottery, pieces of charcoal, broken bones, and a human skeleton having a small, round and very thick skull. M. Morlot, assuming the Roman period to represent an antiquity of from sixteen to eighteen centuries, assigns to the bronze age a date of between 3000 and 4000 years, and to the oldest layer, that of the stone period, an age of from 5000 to 7000 years.

Another calculation has been made by M. Troyon to obtain the approximate date of the remains of an ancient settlement built on piles and preserved in a peat-bog at Chamblon, near Yverdun, on the Lake of Neufchatel. The site of the ancient Roman town of Eburodunum (Yverdun), once on the borders of the lake, and between which and the shore there now intervenes a zone of newly-gained dry land, 2500 feet in breadth, shows the rate at which the bed of the lake has been filled up with river sediment in fifteen centuries. Assuming the lake to have retreated at the same rate before the Roman period, the pile-works of Chamblon, which are of the bronze period, must be at the least 3300 years old.

For the third calculation, communicated to me by M. Morlot, we are indebted to M. Victor Gillieron, of Neuveville, on the Lake of Bienne. It relates to the age of a pile-dwelling, the mammalian bones of which are considered by M. Rutimeyer to indicate the earliest portion of the stone period of Switzerland, and to correspond in age with the settlement of Moosseedorf.

The piles in question occur at the Pont de Thiele, between the lakes of Bienne and Neufchatel. The old convent of St. Jean, founded 750 years ago, and built originally on the margin of the Lake of Bienne, is now at a considerable distance from the shore, and affords a measure of the rate of the gain of land in seven centuries and a half. Assuming that a similar rate of the conversion of water into marshy land prevailed antecedently, we should require an addition of sixty centuries for the growth of the morass intervening between the convent and the aquatic dwelling of Pont de Thiele, in all 6750 years. M. Morlot, after examining the ground, thinks it highly probable that the shape of the bottom on which the morass rests is uniform; but this important point has not yet been tested by boring. The result, if confirmed, would agree exceedingly well with the chronological computation before mentioned of the age of the stone period of Tiniere. As I have not myself visited Switzerland since these chronological speculations were first hazarded, I am unable to enter critically into a discussion of the objections which have been raised to the two first of them, or to decide on the merits of the explanations offered in reply.

IRISH LAKE-DWELLINGS OR CRANNOGES.

The lake-dwellings of the British isles, although not explored as yet with scientific zeal, as those of Switzerland have been in the last ten years, are yet known to be very numerous, and when carefully examined will not fail to throw great light on the history of the bronze and stone periods.

In the lakes of Ireland alone, no less than forty-six examples of artificial islands, called crannoges, have been discovered. They occur in Leitrim, Roscommon, Cavan, Down, Monaghan, Limerick, Meath, King's County, and Tyrone.*

(* W.M. Wylie "Archaeologia" volume 38 1859 page 8.)

One class of these "stockaded islands," as they have been sometimes called, was formed, according to Mr. Digby Wyatt, by placing horizontal oak beams at the bottom of the lake, into which oak posts, from 6 to 8 feet high, were mortised, and held together by cross beams, till a circular enclosure was obtained.

A space of 520 feet diameter, thus enclosed at Lagore, was divided into sundry timbered compartments, which were found filled up with mud or earth, from which were taken "vast quantities of the bones of oxen, swine, deer, goats, sheep, dogs, foxes, horses, and asses." All these were discovered beneath 16 feet of bog, and were used for manure; but specimens of them are said to be preserved in the museum of the Royal Irish Academy. From the same spot were obtained a great collection of antiquities, which, according to Lord Talbot de Malahide and Mr. Wylie, were referable to the ages of stone, bronze, and iron.*

(* W.M. Wylie "Archaeologia" volume 38 1859 page 8, who

cites "Archaeological Journal" volume 6 page 101.)

In Ardekillin Lake, in Roscommon, an islet of an oval form was observed, made of a layer of stones resting on logs of timber. Round this artificial islet or crannoge thus formed was a stone wall raised on oak piles. A careful description has been put on record by Captain Mudge, R.N., of a curious log-cabin discovered by him in 1833 in Drumkellin bog, in Donegal, at a depth of 14 feet from the surface. It was 12 feet square and 9 feet high, being divided into two stories each 4 feet high. The planking was of oak split with wedges of stone, one of which was found in the building. The roof was flat. A staked enclosure had been raised round the cabin, and remains of other similar huts adjoining were seen but not explored. A stone celt, found in the interior of the hut, and a piece of leather sandal, also an arrow-head of flint, and in the bog close at hand a wooden sword, give evidence of the remote antiquity of this building, which may be taken as a type of the early dwellings on the Crannoge islands.

"The whole structure," says Captain Mudge, "was wrought with the rudest kind of implements, and the labour bestowed on it must have been immense. The wood of the mortises was more bruised than cut, as if by a blunt stone chisel."*

(* Mudge "Archaeologia" volume 26.)

Such a chisel lay on the floor of the hut, and by comparing it with the marks of the tool used in forming the mortises, they were found "to correspond exactly, even to the slight curved exterior of the chisel; but the logs had been hewn by a larger instrument, in the shape of an axe. On the floor of the dwelling lay a slab of freestone, 3 feet long and 14 inches thick, in the centre of which was a small pit three quarters of an inch deep, which had been chiselled out. This is presumed to have been used for holding nuts to be cracked by means of one of the round shingle stones, also found there, which had served as a hammer. Some entire hazel-nuts and a great quantity of broken shells were strewed about the floor."

The foundations of the house were made of fine sand, such as is found with shingle on the seashore about 2 miles distant. Below the layer of sand the bog or peat was ascertained, on probing it with an instrument, to be at least 15 feet thick. Although the interior of the building when discovered was full of "bog" or peaty matter, it seems when inhabited to have been surrounded by growing trees, some of the trunks and roots of which are still preserved in their natural position. The depth of overlying peat affords no safe criterion for calculating the age of the cabin or village, for I have shown in the "Principles of Geology" that both in England and Ireland, within historical times, bogs have burst and sent forth great volumes of black mud, which has been known to creep over the country at a slow pace, flowing somewhat at the rate of ordinary lava-currents, and sometimes overwhelming woods and cottages, and leaving a deposit upon them of bog-earth 15 feet thick.

None of these Irish lake-dwellings were built, like those of Helvetia, on platforms supported by piles deeply driven into the mud. "The Crannoge system of Ireland seems," says Mr. Wylie, "well nigh without a parallel in Swiss waters."

PERIOD-CONTINUED.

Delta and Alluvial Plain of the Nile.

Burnt Bricks in Egypt before the Roman Era.

Borings in 1851-54.

Ancient Mounds of the Valley of the Ohio.

Their Antiquity.

Sepulchral Mound at Santos in Brazil.

Delta of the Mississippi.

Ancient Human Remains in Coral Reefs of Florida.

Changes in Physical Geography in the Human Period.

Buried Canoes in Marine Strata near Glasgow.

Upheaval since the Roman Occupation of the Shores of the Firth of Forth.

Fossil Whales near Stirling.

Upraised Marine Strata of Sweden on Shores of the Baltic and the Ocean.

Attempts to compute their Age.

DELTA AND ALLUVIAL PLAIN OF THE NILE.

Some new facts of high interest illustrating the geology of the alluvial land of Egypt were brought to light between the years 1851 and 1854, in consequence of investigations suggested to the Royal Society by Mr. Leonard Horner, and which were partly carried out at the expense of the Society. The practical part of the undertaking was entrusted by Mr. Horner to an Armenian officer of engineers, Hekekyan Bey, who had for many years pursued his scientific studies in England, and was in every way highly qualified for the task.

It was soon found that to obtain the required information respecting the nature, depth, and contents of the Nile mud in various parts of the valley, a larger outlay was called for than had been originally contemplated. This expense the late viceroy, Abbas Pasha, munificently undertook to defray out of his treasury, and his successor, after his death, continued the operations with the same princely liberality.

Several engineers and a body of sixty workmen were employed under the superintendence of Hekekyan Bey, men inured to the climate and able to carry on the sinking of shafts and borings during the hot months, after the waters of the Nile had subsided, and in a season which would have been fatal to Europeans.

The results of chief importance arising out of this inquiry were obtained from two sets of shafts and borings sunk at intervals in lines crossing the great valley from east to west. One of these consisted of no fewer than fifty-one pits and artesian borings, made where the valley is 16 miles wide from side to side between the Arabian and Libyan deserts, in the latitude of Heliopolis, about 8 miles above the apex of the delta. The other line of borings and pits, twenty-seven in number, was in the parallel of Memphis, where the valley is only five miles broad.

Everywhere in these sections the sediment passed through was similar in composition to the ordinary Nile mud of the present day, except near the margin of the valley, where thin layers of quartzose sand, such as is sometimes blown from the adjacent desert by violent winds, were observed to alternate with the loam.

A remarkable absence of lamination and stratification was observed almost universally in the sediment brought up from all points except where the sandy layers above alluded to occurred. Mr. Horner attributes this want of all indication of successive deposition to the extreme thinness of the film of matter which is thrown down annually on the great alluvial plain during the season of inundation. The tenuity of this layer must indeed be extreme, if the French engineers are tolerably correct in their estimate of the amount of sediment formed in a century, which they suppose not to exceed on the average 5 inches. When the waters subside, this thin layer of new soil, exposed to a hot sun, dries rapidly, and clouds of dust are raised by the winds. The superficial deposit, moreover, is disturbed almost everywhere by agricultural labours, and even were this not the case, the action of worms, insects, and the roots of plants would suffice to confound together the deposits of two successive years.

All the remains of organic bodies, such as land-shells, and the bones of quadrupeds, found during the excavations belonged to living species. Bones of the ox, hog, dog, dromedary and ass were not uncommon, but no vestiges of extinct mammalia. No marine shells were anywhere detected; but this was to be expected, as the borings, though they sometimes reached as low as the level of the Mediterranean, were never carried down below it-a circumstance much to be regretted, since where artesian borings have been made in deltas, as in those of the Po and Ganges, to the depth of several hundred feet below the sea level it has been found, contrary to expectation, that the deposits passed through were fluviatile throughout, implying, probably, that a general subsidence of those deltas and alluvial formations has taken place. Whether there has been in like manner a sinking of the land in Egypt, we have as yet no means of proving; but Sir Gardner Wilkinson infers it from the position in the delta on the shore near Alexandria of the tombs commonly called Cleopatra's Baths, which cannot, he says, have been originally built so as to be exposed to the sea which now fills them, but must have stood on land above the level of the Mediterranean. The same author adduces, as additional signs of subsidence, some ruined towns, now half under water, in the Lake Menzaleh, and channels of ancient arms of the Nile submerged with their banks beneath the waters of that same lagoon.

In some instances, the excavations made under the superintendence of Hekekyan Bey were on a large scale for the first 16 or 24 feet, in which cases jars, vases, pots and a small human figure in burnt clay, a copper knife, and other entire articles were dug up; but when water soaking through from the Nile was reached the boring instrument used was too small to allow of more than fragments of works of art being brought up. Pieces of burnt brick and pottery were extracted almost everywhere, and from all depths, even where they sank 60 feet below the surface towards the central parts of the valley. In none of these cases did they get to the bottom of the alluvial soil. It has been objected, among other criticisms, that the Arabs can always find whatever their employers desire to obtain. Even those who are too well acquainted with the sagacity and energy of Hekekyan Bey to suspect him of having been deceived, have suggested that the artificial objects might have fallen into old wells which had been filled up. This notion is inadmissible for many reasons. Of the ninety-five shafts and borings, seventy or more were made far from the sites of towns or villages; and allowing that every field may once have had its well, there would be but small chance of the borings striking upon the site even of a small number of them in seventy experiments.

Others have suggested that the Nile may have wandered over the whole valley, undermining its banks on one side and filling up old channels on the other. It has also been asked whether the delta with the numerous shifting arms of the river may not once have been at every point where the auger pierced.*

(* For a detailed account of these sections, see Mr.

Horner's paper in the "Philosophical Transactions" for 1855

to 1858.)

To all these objections there are two obvious answers:-First, in historical times the Nile has on the whole been very stationary, and has not shifted its position in the valley; secondly, if the mud pierced through had been thrown down by the river in ancient channels, it would have been stratified, and would not have corresponded so closely with inundation mud, we learn from Captain Newbold that he observed in some excavations in the great plain alternations of sand and clay, such as are seen in the modern banks of the Nile; but in the borings made by Hekekyan Bey, such stratification seems scarcely in any case to have been detected.

The great aim of the criticisms above enumerated has been to get rid of the supposed anomaly of finding burnt brick and pottery at depths and places which would give them claim to an antiquity far exceeding that of the Roman domination in Egypt. For until the time of the Romans, it is said, no clay was burnt into bricks in the valley of the Nile. But a distinguished antiquary, Mr. S. Birch, assures me that this notion is altogether erroneous, and that he has under his charge in the British Museum, first, a small rectangular baked brick, which came from a Theban tomb which bears the name of Thothmes, a superintendent of the granaries of the god Amen Ra, the style of art, inscription, and name, showing that it is as old as the 18th dynasty (about 1450 B.C.); secondly, a brick bearing an inscription, partly obliterated, but ending with the words "of the temple of Amen Ra." This brick, decidedly long anterior to the Roman dominion, is referred conjecturally, by Mr. Birch, to the 19th dynasty, or 1300 B.C. Sir Gardner Wilkinson has also in his possession pieces of mortar, which he took from each of the three great pyramids, in which bits of broken pottery and of burnt clay or brick are embedded.

M. Girard, of the French expedition to Egypt, supposed the average rate of the increase of Nile mud on the plain between Assouan and Cairo to be five English inches in a century. This conclusion, according to Mr. Horner, is very vague, and founded on insufficient data; the amount of matter thrown down by the waters in different parts of the plain varying so much that to strike an average with any approach to accuracy must be most difficult. Were we to assume six inches in a century, the burnt brick met with at a depth of 60 feet would be 12,000 years old.

Another fragment of red brick was found by Linant Bey, in a boring 72 feet deep, being 2 or 3 feet below the level of the Mediterranean, in the parallel of the apex of the delta, 200 metres distant from the river, on the Libyan side of the Rosetta branch.*

(* Horner "Philosophical Transactions" 1858.)

M. Rosiere, in the great French work on Egypt, has estimated the mean rate of deposit of sediment in the delta at 2 1/4 inches in a century;* were we to take 2 1/2 inches, a work of art 72 feet deep must have been buried more than 30,000 years ago.

(* Description de l'Egypte "Histoire Naturelle" tome 2 page

494.)

But if the boring of Linant Bey was made where an arm of the river had been silted up at a time when the apex of the delta was somewhat farther south, or more distant from the sea than now, the brick in question might be comparatively very modern.

The experiments instituted by Mr. Horner at the pedestal of the fallen statue of King Rameses at Memphis, in the hope of obtaining an accurate chronometric scale for testing the age of a given thickness of Nile sediment, are held by some experienced Egyptologists not to be satisfactory, on the ground of the uncertainty of the rate of deposit accumulated at that locality. The point sought to be determined was the exact amount of Nile mud which had accumulated there since the time when that statue is supposed by some antiquaries to have been erected. Could we have obtained possession of such a measure, the rate of deposition might be judged of, approximately at least, whenever similar mud was observed in other places, or below the foundations of those same monuments. But the ancient Egyptians are known to have been in the habit of enclosing with embankments the areas on which they erected temples, statues, and obelisks, so as to exclude the waters of the Nile; and the point of time to be ascertained, in every case where we find a monument buried to a certain depth in mud, as at Memphis and Heliopolis, is the era when the city fell into such decay that the ancient embankments were neglected, and the river allowed to inundate the site of the temple, obelisk, or statue.

Even if we knew the date of the abandonment of such embankments, the enclosed areas would not afford a favourable opportunity for ascertaining the average rate of deposit in the alluvial plain; for Herodotus tells us that in his time those spots from which the Nile waters had been shut out for centuries appeared sunk, and could be looked down into from the surrounding grounds, which had been raised by the gradual accumulation over them of sediment annually thrown down. If the waters at length should break into such depressions, they must at first carry with them into the enclosure much mud washed from the steep surrounding banks, so that a greater quantity would be deposited in a few years than perhaps in as many centuries on the great plain outside the depressed area, where no such disturbing causes intervened.

ANCIENT MOUNDS OF THE VALLEY OF THE OHIO.

As I have already given several European examples of monuments of prehistoric date belonging to the Recent period, I will now turn to the American continent. Before the scientific investigation by Messrs. Squier and Davis of the "Ancient Monuments of the Mississippi Valley",* no one suspected that the plains of that river had been occupied, for ages before the French and British colonists settled there, by a nation of older date and more advanced in the arts than the Red Indians whom the Europeans found there.

(* "Smithsonian Contributions" volume 1 1847.)

There are hundreds of large mounds in the basin of the Mississippi, and especially in the valleys of the Ohio and its tributaries, which have served, some of them for temples, others for outlook or defence, and others for sepulture. The unknown people by whom they were constructed, judging by the form of several skulls dug out of the burial-places, were of the Mexican or Toltec race. Some of the earthworks are on so grand a scale as to embrace areas of 50 or 100 acres within a simple enclosure, and the solid contents of one mould are estimated at 20 million of cubic feet, so that four of them would be more than equal in bulk to the Great Pyramid of Egypt, which comprises 75 million. From several of these repositories pottery and ornamental sculpture have been taken, and various articles in silver and copper, also stone weapons, some composed of hornstone unpolished, and much resembling in shape some ancient flint implements found near Amiens and other places in Europe, to be alluded to in the sequel.

It is clear that the Ohio mound-builders had commercial intercourse with the natives of distant regions, for among the buried articles some are made of native copper from Lake Superior, and there are also found mica from the Alleghenies, sea-shells from the Gulf of Mexico, and obsidian from the Mexican mountains.

The extraordinary number of the mounds implies a long period, during which a settled agricultural population had made considerable progress in civilisation, so as to require large temples for their religious rites, and extensive fortifications to protect them from their enemies. The mounds were almost all confined to fertile valleys or alluvial plains, and some at least are so ancient that rivers have had time since their construction to encroach on the lower terraces which support them, and again to recede for the distance of nearly a mile, after having undermined and destroyed a part of the works. When the first European settlers entered the valley of the Ohio, they found the whole region covered with an uninterrupted forest, and tenanted by the Red Indian hunter, who roamed over it without any fixed abode, or any traditionary connection with his more civilised predecessors. The only positive data as yet obtained for calculating the minimum of time which must have elapsed since the mounds were abandoned, have been derived from the age and nature of the trees found growing on some of these earthworks. When I visited Marietta in 1842, Dr. Hildreth took me to one of the mounds, and showed me where he had seen a tree growing on it, the trunk of which when cut down displayed eight hundred rings of annual growth.*

(* Lyell's "Travels in North America" volume 2 page 29.)

But the late General Harrison, President in 1841 of the United States, who was well skilled in woodcraft, has remarked, in a memoir on this subject, that several generations of trees must have lived and died before the mounds could have been overspread with that variety of species which they supported when the white man first beheld them, for the number and kinds of trees were precisely the same as those which distinguished the surrounding forest. "We may be sure," observed Harrison, "that no trees were allowed to grow so long as the earthworks were in use; and when they were forsaken, the ground, like all newly cleared land in Ohio, would for a time be monopolised by one or two species of tree, such as the yellow locust and the black or white walnut. When the individuals which were the first to get possession of the ground had died out one after the other, they would in many cases, instead of being replaced by the same species, be succeeded (by virtue of the law which makes a rotation of crops profitable in agriculture) by other kinds, till at last, after a great number of centuries (several thousand years, perhaps), that remarkable diversity of species characteristic of North America, and far exceeding what is seen in European forests, would be established."

MOUNDS OF SANTOS IN BRAZIL.

I will next say a few words respecting certain human bones embedded in a solid rock at Santos in Brazil, to which I called attention in my "Travels in North America" in 1842.*

(* Volume 1 page 200.)

I then imagined the deposit containing them to be of submarine origin-an opinion which I have long ceased to entertain. We learn from a memoir of Dr. Meigs that the River Santos has undermined a large mound, 14 feet in height, and about 3 acres in area, covered with trees, near the town of St. Paul, and has exposed to view many skeletons, all inclined at angles between 20 and 25 degrees, and all placed in a similar east and west position.*

(* Meigs "Transactions of the American Philosophical

Society" 1828 page 285.)

Seeing, in the Museum of Philadelphia, fragments of the calcareous stone or tufa from this spot, containing a human skull with teeth, and in the same matrix, oysters with serpulae attached, I at first concluded that the whole deposit had been formed beneath the waters of the sea, or at least, that it had been submerged after its origin, and again upheaved; also, that there had been time since its emergence for the growth on it of a forest of large trees. But after reading again, with more care, the original memoir of Dr. Meigs, I cannot doubt that the shells, like those of eatable kinds, so often accumulated in the mounds of the North American Indians not far from the sea, may have been brought to the place and heaped up with other materials at the time when the bodies were buried. Subsequently, the whole artificial earthwork, with its shells and skeletons, may have been bound together into a solid stone by the infiltration of carbonate of lime, and the mound may therefore be of no higher antiquity than some of those above alluded to on the Ohio, which, as we have seen, have in like manner been exposed in the course of ages to the encroachments and undermining action of rivers.

DELTA OF THE MISSISSIPPI.

I have shown in my "Travels in North America" that the deposits forming the delta and alluvial plain of the Mississippi consist of sedimentary matter, extending over an area of 30,000 square miles, and known in some parts to be several hundred feet deep. Although we cannot estimate correctly how many years it may have required for the river to bring down from the upper country so large a quantity of earthy matter-the data for such a computation being as yet incomplete-we may still approximate to a minimum of the time which such an operation must have taken, by ascertaining experimentally the annual discharge of water by the Mississippi, and the mean annual amount of solid matter contained in its waters. The lowest estimate of the time required would lead us to assign a high antiquity, amounting to many tens of thousands of years (probably more than 100,000) to the existing delta.

Whether all or how much of this formation may belong to the recent period, as above defined, I cannot pretend to decide, but in one part of the modern delta near New Orleans, a large excavation has been made for gas-works, where a succession of beds, almost wholly made up of vegetable matter, has been passed through, such as we now see forming in the cypress swamps of the neighbourhood, where the deciduous cypress (Taxodium distichum), with its strong and spreading roots, plays a conspicuous part. In this excavation, at the depth of sixteen feet from the surface, beneath four buried forests superimposed one upon the other, the workmen are stated by Dr. B. Dowler to have found some charcoal and a human skeleton, the cranium of which is said to belong to the aboriginal type of the Red Indian race. As the discovery in question had not been made when I saw the excavation in progress at the gas-works in 1846, I cannot form an opinion as to the value of the chronological calculations which have led Dr. Dowler to ascribe to this skeleton an antiquity of 50,000 years. In several sections, both natural in the banks of the Mississippi and its numerous arms, and where artificial canals had been cut, I observed erect stumps of trees, with their roots attached, buried in strata at different heights, one over the other. I also remarked, that many cypresses which had been cut through, exhibited many hundreds of rings of annual growth, and it then struck me that nowhere in the world could the geologist enjoy a more favourable opportunity for estimating in years the duration of certain portions of the Recent epoch.*

(* Dowler cited by Dr. W. Usher in Nott and Gliddon's "Types

of Mankind" page 352.)

CORAL REEFS OF FLORIDA.

Professor Agassiz has described a low portion of the peninsula of Florida as consisting of numerous reefs of coral, which have grown in succession so as to give rise to a continual annexation of land, gained gradually from the sea in a southerly direction. This growth is still in full activity, and assuming the rate of advance of the land to be one foot in a century, the reefs being built up from a depth of 75 feet, and that each reef has in its turn added ten miles to the coast, Professor Agassiz calculates that it has taken 135,000 years to form the southern half of this peninsula. Yet the whole is of Post-Tertiary origin, the fossil zoophytes and shells being all of the same species as those now inhabiting the neighbouring sea.*

(* Agassiz in Nott and Gliddon ibid. page 352.)

In a calcareous conglomerate forming part of the above-mentioned series of reefs, and supposed by Agassiz, in accordance with his mode of estimating the rate of growth of those reefs, to be about 10,000 years old, some fossil human remains were found by Count Pourtales. They consisted of jaws and teeth, with some bones of the foot.

RECENT DEPOSITS OF SEAS AND LAKES.

I have shown, in the "Principles of Geology," where the recent changes of the earth illustrative of geology are described at length, that the deposits accumulated at the bottom of lakes and seas within the last 4000 or 5000 years can neither be insignificant in volume or extent. They lie hidden, for the most part, from our sight; but we have opportunities of examining them at certain points where newly-gained land in the deltas of rivers has been cut through during floods, or where coral reefs are growing rapidly, or where the bed of a sea or lake has been heaved up by subterranean movements and laid dry.

As examples of such changes of level by which marine deposits of the Recent period have become accessible to human observation, I have adduced the strata near Naples in which the Temple of Serapis at Pozzuoli was entombed.*

(* "Principles of Geology" Index "Serapis.")

These upraised strata, the highest of which are about 25 feet above the level of the sea, form a terrace skirting the eastern shore of the Bay of Baiae. They consist partly of clay, partly of volcanic matter, and contain fragments of sculpture, pottery, and the remains of buildings, together with great numbers of shells, retaining in part their colour, and of the same species as those now inhabiting the neighbouring sea. Their emergence can be proved to have taken place since the beginning of the sixteenth century. [Note 5]

In the same work, as an example of a freshwater deposit of the Recent period, I have described certain strata in Cashmere, a country where violent earthquakes, attended by alterations in the level of the ground, are frequent, in which freshwater shells of species now inhabiting the lakes and rivers of that region are embedded, together with the remains of pottery, often at the depth of fifty feet, and in which a splendid Hindoo temple has lately been discovered, and laid open to view by the removal of the lacustrine silt which had enveloped it for four or five centuries.

In the same treatise it is stated that the west coast of South America, between the Andes and the Pacific, is a great theatre of earthquake movements, and that permanent upheavals of the land of several feet at a time have been experienced since the discovery of America. In various parts of the littoral region of Chile and Peru, strata have been observed enclosing shells in abundance, all agreeing specifically with those now swarming in the Pacific. In one bed of this kind, in the island of San Lorenzo, near Lima, Mr. Darwin found, at the altitude of 85 feet above the sea, pieces of cotton-thread, plaited rush, and the head of a stalk of Indian corn, the whole of which had evidently been embedded with the shells. At the same height, on the neighbouring mainland, he found other signs corroborating the opinion that the ancient bed of the sea had there also been uplifted 85 feet since the region was first peopled by the Peruvian race. But similar shelly masses are also met with at much higher elevations, at innumerable points between the Chilean and Peruvian Andes and the sea-coast, in which no human remains have as yet been observed. The preservation for an indefinite period of such perishable substances as thread is explained by the entire absence of rain in Peru. The same articles, had they been enclosed in the permeable sands of an European raised beach, or in any country where rain falls even for a small part of the year, would probably have disappeared entirely [Note 6]

In the literature of the eighteenth century, we find frequent allusion to the "era of existing continents," a period supposed to have coincided in date with the first appearance of Man upon the earth, since which event it was imagined that the relative level of the sea and land had remained stationary, no important geographical changes having occurred, except some slight additions to the deltas of rivers, or the loss of narrow strips of land where the sea had encroached upon its shores. But modern observations have tended continually to dispel this delusion, and the geologist is now convinced that at no given era of the past have the boundaries of land and sea, or the height of the one and depth of the other, or the geographical range of the species inhabiting them, whether of animals or plants, become fixed and unchangeable. Of the extent to which fluctuations have been going on since the globe had already become the dwelling-place of Man, some idea may be formed from the examples which I shall give in this and the next nine chapters.

UPHEAVAL SINCE THE HUMAN PERIOD OF THE CENTRAL DISTRICT OF SCOTLAND.

[Note 7] It has long been a fact familiar to geologists, that, both on the east and west coasts of the central part of Scotland, there are lines of raised beaches, containing marine shells of the same species as those now inhabiting the neighbouring sea.*

(* R. Chambers "Sea Margins" 1848 and papers by Mr. Smith of

Jordan Hill "Memoirs of the Wernerian Society" volume 8 and

by Mr. C. Maclaren. )

The two most marked of these littoral deposits occur at heights of about 50 and 25 feet above high-water mark, that of 50 feet being considered as the more ancient, and owing its superior elevation to a continuance of the upheaving movement. They are seen in some places to rest on the boulder clay of the glacial period, which will be described in future chapters.

In those districts where large rivers, such as the Clyde, Forth, and Tay, enter the sea, the lower of the two deposits, or that of 25 feet, expands into a terrace fringing the estuaries, and varying in breadth from a few yards to several miles. Of this nature are the flat lands which occur along the margin of the Clyde at Glasgow, which consist of finely laminated sand, silt, and clay. Mr. John Buchanan, a zealous antiquary, writing in 1855, informs us that in the course of the eighty years preceding that date, no less than seventeen canoes had been dug out of this estuarine silt, and that he had personally inspected a large number of them before they were exhumed. Five of them lay buried in silt under the streets of Glasgow, one in a vertical position with the prow uppermost as if it had sunk in a storm. In the inside of it were a number of marine shells. Twelve other canoes were found about 100 yards back from the river, at the average depth of about 19 feet from the surface of the soil, or 7 feet above high-water mark; but a few of them were only 4 or 5 feet deep, and consequently more than 20 feet above the sea-level. One was sticking in the sand at an angle of 45 degrees, another had been capsized and lay bottom uppermost; all the rest were in a horizontal position, as if they had sunk in smooth water.*

(* J. Buchanan "Report of the British Association" 1855 page

80; also "Glasgow, Past and Present" 1856.)

Almost every one of these ancient boats was formed out of a single oak-stem, hollowed out by blunt tools, probably stone axes, aided by the action of fire; a few were cut beautifully smooth, evidently with metallic tools. Hence a gradation could be traced from a pattern of extreme rudeness to one showing great mechanical ingenuity. Two of them were built of planks, one of the two, dug up on the property of Bankton in 1853, being 18 feet in length, and very elaborately constructed. Its prow was not unlike the beak of an antique galley; its stern, formed of a triangular-shaped piece of oak, fitted in exactly like those of our day. The planks were fastened to the ribs, partly by singularly shaped oaken pins, and partly by what must have been square nails of some kind of metal; these had entirely disappeared, but some of the oaken pins remained. This boat had been upset, and was lying keel uppermost, with the prow pointing straight up the river. In one of the canoes, a beautifully polished celt or axe of greenstone was found, in the bottom of another a plug of cork, which, as Mr. Geikie remarks, "could only have come from the latitudes of Spain, Southern France, or Italy."*

(* Geikie, "Quarterly Journal of the Geological Society"

volume 18 1862 page 224.)

There can be no doubt that some of these buried vessels are of far more ancient date than others. Those most roughly hewn, may be relics of the stone period; those more smoothly cut, of the bronze age; and the regularly built boat of Bankton may perhaps come within the age of iron. The occurrence of all of them in one and the same upraised marine formation by no means implies that they belong to the same era, for in the beds of all great rivers and estuaries, there are changes continually in progress brought about by the deposition, removal, and redeposition of gravel, sand, and fine sediment, and by the shifting of the channel of the main currents from year to year, and from century to century. All these it behoves the geologist and antiquary to bear in mind, so as to be always on their guard, when they are endeavouring to settle the relative date, whether of objects of art or of organic remains embedded in any set of alluvial strata. Some judicious observations on this head occur in Mr. Geikie's memoir above cited, which are so much in point that I shall give them in full, and in his own words.

"The relative position in the silt, from which the canoes were exhumed, could help us little in any attempt to ascertain their relative ages, unless they had been found vertically above each other. The varying depths of an estuary, its banks of silt and sand, the set of its currents, and the influence of its tides in scouring out alluvium from some parts of its bottom and redepositing it in others, are circumstances which require to be taken into account in all such calculations. Mere coincidence of depth from the present surface of the ground, which is tolerably uniform in level, by no means necessarily proves contemporaneous deposition. Nor would such an inference follow even from the occurrence of the remains in distant parts of the very same stratum. A canoe might be capsized and sent to the bottom just beneath low-water mark; another might experience a similar fate on the following day, but in the middle of the channel. Both would become silted up on the floor of the estuary; but as that floor would be perhaps 20 feet deeper in the centre than towards the margin of the river, the one canoe might actually be twenty feet deeper in the alluvium than the other; and on the upheaval of the alluvial deposits, if we were to argue merely from the depth at which the remains were embedded, we should pronounce the canoe found at the one locality to be immensely older than the other, seeing that the fine mud of the estuary is deposited very slowly and that it must therefore have taken a long period to form so great a thickness as 20 feet. Again, the tides and currents of the estuary, by changing their direction, might sweep away a considerable mass of alluvium from the bottom, laying bare a canoe that may have foundered many centuries before. After the lapse of so long an interval, another vessel might go to the bottom in the same locality and be there covered up with the older one on the same general plane. These two vessels, found in such a position, would naturally be classed together as of the same age, and yet it is demonstrable that a very long period may have elapsed between the date of the one and that of the other. Such an association of these canoes, therefore, cannot be regarded as proving synchronous deposition; nor, on the other hand, can we affirm any difference of age from mere relative position, unless we see one canoe actually buried beneath another."*

(* Geikie, "Quarterly Journal of the Geological Society"

volume 18 1862, page 222.)

At the time when the ancient vessels, above described, were navigating the waters where the city of Glasgow now stands, the whole of the low lands which bordered the present estuary of the Clyde formed the bed of a shallow sea. The emergence appears to have taken place gradually and by intermittent movements, for Mr. Buchanan describes several narrow terraces one above the other on the site of the city itself, with steep intervening slopes composed of the laminated estuary formation. Each terrace and steep slope probably mark pauses in the process of upheaval, during which low cliffs were formed, with beaches at their base. Five of the canoes were found within the precincts of the city at different heights on or near such terraces.

As to the date of the upheaval, the greater part of it cannot be assigned to the stone period, but must have taken place after tools of metal had come into use.

Until lately, when attempts were made to estimate the probable antiquity of such changes of level, it was confidently assumed, as a safe starting-point, that no alteration had occurred in the relative level of land and sea, in the central district of Scotland, since the construction of the Roman or Pictish wall (the "Wall of Antonine"), which reached from the Firth of Forth to that of the Clyde. The two extremities, it was said, of this ancient structure, bear such a relation to the present level of the two estuaries, that neither subsidence nor elevation of the land could have occurred for seventeen centuries at least.

But Mr. Geikie has lately shown that a depression of 25 feet on the Forth would not lay the eastern extremity of the Roman wall at Carriden under water, and he was therefore desirous of knowing whether the western end of the same would be submerged by a similar amount of subsidence. It has always been acknowledged that the wall terminated upon an eminence called the Chapel Hill, near the village of West Kilpatrick, on the Clyde. The foot of this hill, Mr. Geikie estimates to be about 25 or 27 feet above high-water mark, so that a subsidence of 25 feet could not lay it under water. Antiquaries have sometimes wondered that the Romans did not carry the wall farther west than this Chapel Hill; but Mr. Geikie now suggests, in explanation, that all the low land at present intervening between that point and the mouth of the Clyde, was sixteen or seventeen centuries ago, washed by the tides at high water.

The wall of Antonine, therefore, yields no evidence in favour of the land having remained stationary since the time of the Romans, but on the contrary, appears to indicate that since its erection the land has actually risen. Recent explorations by Mr. Geikie and Dr. Young, of the sites of the old Roman harbours along the southern margin of the Firth of Forth, lead to similar inferences. In the first place, it has long been known that there is a raised beach containing marine shells of living littoral species, at a height of about 25 feet, at Leith, as well as at other places along the coast above and below Edinburgh. Inveresk, a few miles below that city, is the site of an ancient Roman port, and if we suppose the sea at high water to have washed the foot of the heights on which the town stood, the tide would have ascended far up the valley of the Esk, and would have made the mouth of that river a safe and commodious harbour; whereas, had it been a shoaling estuary, as at present, it is difficult to see how the Romans should have made choice of it as a port.

At Cramond, at the mouth of the river Almond, above Edinburgh, was Alaterva, the chief Roman harbour on the southern coast of the Forth, where numerous coins, urns, sculptured stones and the remnant of a harbour have been detected. The old Roman quays built along what must then have been the sea margin, have been found on what is now dry land, and although some silt carried down in suspension by the waters of the Forth may account for a part of the gain of low land, we yet require an upward movement of about 20 feet to explain the growth of the dreary expanse of mud now stretching along the shore and extending outwards, where it attains its greatest breadth, well-nigh two miles, across which vessels, even of light burden, can now only venture at full tide. Had these shoals existed eighteen centuries ago, they would have prevented the Romans from selecting this as their chief port; whereas, if the land were now to sink 20 feet, Cramond would unquestionably be the best natural harbour along the whole of the south side of the Forth.*

(* Geikie, "Edinburgh New Philosophical Journal" for July

1861.)

Corresponding in level with the raised beach at Leith, above mentioned (or about 25 feet above high-water mark), is the Carse of Stirling, a low tract of land consisting of loamy and peaty beds, in which several skeletons of whales of large size have been found. One of these was dug up at Airthrie,* near Stirling, about a mile from the river, and 7 miles from the sea.

(* Bald, "Edinburgh Philosophical Journal" 1 page 393 and

"Memoirs of the Wernerian Society" 3 page 327.)

Mr. Bald mentions that near it were found two pieces of stag's horn, artificially cut, through one of which a hole, about an inch in diameter, had been perforated. Another whale, 85 feet long, was found at Dunmore, a few miles below Stirling,* which, like that of Airthrie, lay about 20 feet above high-water mark.

(* "Edinburgh Philosophical Journal" 11 pages 220, 415.)

Three other skeletons of whales were found at Blair Drummond, between the years 1819 and 1824, 7 miles up the estuary above Stirling,* also at an elevation of between 20 and 30 feet above the sea. Near two of these whales, pointed instruments of deer's horn were found, one of which retained part of a wooden handle, probably preserved by having been enclosed in peat. This weapon is now in the museum at Edinburgh.

(* "Memoirs of the Wernerian Society" volume 5 page 440.)

The position of these fossil whales and bone implements, and still more of an iron anchor found in the Carse of Falkirk, below Stirling, shows that the upheaval by which the raised beach of Leith was laid dry extended far westward probably as far as the Clyde, where, as we have seen, marine strata containing buried canoes rise to a similar height above the sea.

The same upward movement which reached simultaneously east and west from sea to sea was also felt as far north as the estuary of the Tay. This may be inferred from the Celtic name of Inch being attached to many hillocks, which rise above the general level of the alluvial plains, implying that these eminences were once surrounded by water or marshy ground. At various localities also in the silt of the Carse of Gowrie iron implements have been found.

The raised beach, also containing a great number of marine shells of recent species, traced up to a height of 14 feet above the sea by Mr. W.J. Hamilton at Elie, on the southern coast of Fife, is doubtless another effect of the same extensive upheaval.*

(* "Proceedings of the Geological Society" volume 2 1833

page 280.)

A similar movement would also account for some changes which antiquaries have recorded much farther south, on the borders of the Solway Firth; though in this case, as in that of the estuary of the Forth, the conversion of sea into land has always been referred to the silting up of estuaries, and not to upheaval. Thus Horsley insists on the difficulty of explaining the position of certain Roman stations, on the Solway, the Forth, and the Clyde, without assuming that the sea has been excluded from certain areas which it formerly occupied.*

(* "Britannia" page 157 1860.)

On a review of the whole evidence, geological and archaeological, afforded by the Scottish coast-line, we may conclude that the last upheaval of 25 feet took place not only since the first human population settled in the island; but long after metallic implements had come into use, and there seems even a strong presumption in favour of the opinion that the date of the elevation may have been subsequent to the Roman occupation.

But the 25 feet rise is only the last stage of a long antecedent process of elevation, for examples of Recent marine shells have been observed 40 feet and upwards above the sea in Ayrshire. At one of these localities, Mr. Smith of Jordanhill informs me that a rude ornament made of cannel coal has been found on the coast in the parish of Dundonald, lying 50 feet above the sea-level, on the surface of the boulder-clay or till, and covered with gravel containing marine shells. If we suppose the upward movement to have been uniform in central Scotland before and after the Roman era, and assume that as 25 feet indicate seventeen centuries, so 50 feet imply a lapse of twice that number, or 3400 years, we should then carry back the date of the ornament in question to fifteen centuries before our era, or to the days of Pharaoh, and the period usually assigned to the exodus of the Israelites from Egypt. [Note 8]

But all such estimates must be considered, in the present state of science, as tentative and conjectural, since the rate of movement of the land may not have been uniform, and its direction not always upwards, and there may have been long stationary periods, one of which of more than usual duration seems indicated by the 50-foot raised beach, which has been traced for vast distances along the western coast of Scotland.

COAST OF CORNWALL.

Sir H. De la Beche has adduced several proofs of changes of level, in the course of the human period, in his "Report on the Geology of Cornwall and Devon," 1839. He mentions (page 406) that several human skulls and works of art, buried in an estuary deposit, were found in mining gravel for tin at Pentuan, near St. Austell, the skulls lying at the depth of 40 feet from the surface, and others at Carnon at the depth of 53 feet. The overlying strata were marine, containing sea-shells of living species, and bones of whales, besides the remains of several living species of mammalia.

Other examples of works of art, such as stone hatchets, canoes, and ships, buried in ancient river-beds in England, and in peat and shell-marl, I have mentioned in my work before cited.

SWEDEN AND NORWAY.

In the same work I have shown that near Stockholm, in Sweden, there occur, at slight elevations above the sea-level, horizontal beds of sand, loam, and marl, containing the same peculiar assemblage of testacea which now live in the brackish waters of the Baltic. Mingled with these, at different depths, have been detected various works of art implying a rude state of civilization, and some vessels built before the introduction of iron, and even the remains of an ancient hut, the marine strata containing it, which had been formed during a previous depression, having been upraised, so that the upper beds are now 60 feet higher than the surface of the Baltic. In the neighbourhood of these recent strata, both to the north-west and south of Stockholm, other deposits similar in mineral composition occur, which ascend to greater heights, in which precisely the same assemblage of fossil shells is met with, but without any intermixture, so far as is yet known, of human bones or fabricated articles.

On the opposite or western coast of Sweden, at Uddevalla, Post-Tertiary strata, containing recent shells, not of that brackish water character peculiar to the Baltic, but such as now live in the Northern Ocean, ascend to the height of 200 feet; and beds of clay and sand of the same age attain elevations of 300 and even 600 feet in Norway, where they have been usually described as "raised beaches." They are, however, thick deposits of submarine origin, spreading far and wide, and filling valleys in the granite and gneiss, just as the Tertiary formations, in different parts of Europe, cover or fill depressions in the older rocks.

Although the fossil fauna characterising these upraised sands and clays consists exclusively of existing northern species of testacea, it is more than probable that they may not all belong to that division of the Pleistocene strata which we are now considering. If the contemporary mammalia were known, they would, in all likelihood, be found to be referable, at least in part, to extinct species; for, according to Loven (an able living naturalist of Norway), the species do not constitute such an assemblage as now inhabits corresponding latitudes in the North Sea. On the contrary, they decidedly represent a more arctic fauna. In order to find the same species flourishing in equal abundance, or in many cases to find them at all, we must go northwards to higher latitudes than Uddevalla in Sweden, or even nearer the pole than Central Norway.

Judging by the uniformity of climate now prevailing from century to century, and the insensible rate of variation in the geographical distribution of organic beings in our own times, we may presume that an extremely lengthened period was required even for so slight a modification in the range of the molluscous fauna, as that of which the evidence is here brought to light. There are also other independent reasons for suspecting that the antiquity of these deposits may be indefinitely great as compared to the historical period. I allude to their present elevation above the sea, some of them rising, in Norway, to the height of 600 feet or more. The upward movement now in progress in parts of Norway and Sweden extends, as I have elsewhere shown,* throughout an area about 1000 miles north and south, and for an unknown distance east and west, the amount of elevation always increasing as we proceed towards the North Cape, where it is said to equal 5 feet in a century.

(* "Principles" 9th edition chapter 30.)

If we could assume that there had been an average of 2 1/2 feet in each hundred years for the last fifty centuries, this would give an elevation of 125 feet in that period. In other words, it would follow that the shores, and a considerable area of the former bed of the North Sea, had been uplifted vertically to that amount, and converted into land in the course of the last 5000 years. A mean rate of continuous vertical elevation of 2 1/2 feet in a century would, I conceive, be a high average; yet, even if this be assumed, it would require 24,000 years for parts of the sea-coast of Norway, where the Pleistocene marine strata occur, to attain the height of 600 feet. [Note 9]