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this: More than one instance had been noted of the finding of flint implements, apparently the work of men, in association with bones 84 of various animals, such as hyenas, mammoths, musk-sheep, and others, which, as we have just seen, lived in Europe during the Glacial Age. In a number of cases such finds had been made in caves. But for a long time no one attributed any especial value to these discoveries, and various were the explanations given to account for such commingling. A French geologist, by the name of Boucher DePerthes, had noted the occurrence of similar flint implements, and bones of these extinct animals, in a gravel pit on the banks of the Somme, near Abbeville, France. He was convinced that they proved the existence of man at the time these ancient animals lived in Europe. But no one paid any attention to his opinions on this subject, and a collection of these implements, which he took to Paris in 1839, was scarcely noticed by the scientific world. They were certainly very rude, and presented but indistinct traces of chipping, and perhaps it is not strange that he failed to convince any one of their importance. He therefore determined to make a thorough and systematic exploration of these beds at Abbeville. In 1847 he published his great work on this subject, giving over sixteen hundred cuts of the various articles he had found, claiming that they were proof positive of the presence of man when the gravels were depositing. Picture of Flint Implements, so-called.------ Now there are several questions to be answered before the conclusions of the French geologist can be accepted. In the first place, are these so-called flint implements of human workmanship? From our illustrations, we see that they are of an oval shape, tending to a cutting edge all around, and generally more or less pointed at one end. The testimony of 85 all competent persons who have examined them is, that however rude they may be, they were undoubtedly fashioned by man. Dr. C. C. Abbott has made some remarks on implements found in another locality, equally applicable to the ones in question. He says: "We find, on comparing a specimen of these chipped stones with an accidentally fractured pebble, that the chipped surfaces of the former all tend toward the production of a cutting edge, and there is no portion of the stone detached which does not add to the availability of the supposed implement as such; while in the case of a pebble that has been accidentally broken, there is necessarily all absence of design in the fracturing." Like the watch found on the moor, they show such manifest evidence of design, that we can not doubt that they were produced by the hand of man. But it is not enough to know that they are artificial, we must also know that they are of the same age as the beds in which they are found. Section of Gravel Pit.----------- This cut represents a section of a gravel pit at St. Acheul, on the Somme. The implements are nearly always found in the lowest strata, which is a bed of gravel from ten to fourteen feet thick. Overlying this are beds of marl, loam, and surface soil, comprising in all a depth of fourteen feet. It has been suggested that the implements are comparatively recent, and have sunk down from above by their own weight, or perhaps have been buried in artificial excavations. The beds are however too compact to admit of any supposition that they may have been sunk there; and if buried in any excavation, evident traces of such 86 excavation would have remained. We can account for their presence there in no other way than, that when the river rolled along at that high elevation, and deposited great beds of sand, these implements were someway lost in its waters, and became buried in the gravel deposits. Finally, we have to consider the age of the deposits. This is a question that can be answered only by geologists, and we may be sure that more than ordinary attention has been bestowed upon them. The remains of many animals characteristic of the Glacial Age were found in the beds at Abbeville. These include those of the elephants, rhinoceros, hyenas, cave-bear, and cave-lion. In the formation of these gravel beds, ice has undoubtedly played quite an important part. Bowlders that could have got there only by the aid of ice, are found in several localities. Evidence gathered from a great many different sources all establish the fact that these gravels date as far back as the close of the Glacial Age at least, and there are some reasons for supposing them to be interglacial. We can easily see that the melting away of the immense glaciers that we have been describing would produce vast floods in the rivers, and it is perhaps owing to the presence of such swollen rivers that are due the great beds of surface soil, called loam or loess, found in all the river valleys of France and Germany. These deposits frequently overlie the gravel beds. They are then of a later date than the beds in which are found such convincing proofs of the presence of man, and if they themselves date from the close of the Glacial Age, it is no longer a question whether the gravel beds themselves belong to that age. Thus we see that we can no longer escape the conclusions of Boucher DePerthes. 87 The discovery of rudely worked flints in the drift of the Somme River thus establishes the fact that some time during the Glacial Age, man in a Paleolithic state lived in France. Geological terms convey to us no definite ideas as to the lapse of time, and we have an instinctive desire to substitute for them some term of years. In most cases this is impossible, as we have no means to measure the flight of past time, nor are we yet prepared to discuss the question of time, since to do so we must learn a great deal more about the cause of the Glacial Age. We might, however, cite statements which can not fail to impress us with the fact that a great extent of time has passed. In the case of the river Somme we have a valley in some places a mile or more in width, and about two hundred feet in depth. This has mostly been excavated in chalk rock. Taking our present large rivers as a basis, it would require from one to two hundred thousand years for the Somme to perform this work. It will not do, however, to take the present action of our rivers as a guide, since we have every reason to suppose this work went forward much more rapidly in past times. But we can not escape the conclusion that it demands a very long time indeed to explain it. The valley has remained in its present shape long enough to admit the formation of great beds of peat in some portions. Peat is formed by the decomposition of vegetable growth. Its growth is in all cases slow, depending entirely upon local circumstances. European scholars who have made peat formation a special study assure us that to form such immense beds as occur near Abbeville, several thousand years are required, even under the most favorable conditions. Yet we would be scarcely willing to rest such important conclusions as 88 the foregoing on the researches of one individual, or in one locality. As already stated, DePerthes made his discoveries public in 1847. Yet they were so opposed to all that had been believed previously, that but few took the pains to investigate for themselves. In 1853, Dr. Rigollot, of Amiens, who had been skeptical as to DePerthes, commenced to look for himself in the gravel beds at St. Acheul, about nine miles below Abbeville. As might be expected, he was soon convinced. Picture of Paleolithic Flint, England.------ It may be said that the scientific world formally accepted the new theory when such English scientists as Evans, Falconer, Lyell, and Prestwich reported in its favor. Since that time, many discoveries of ancient implements have been made at various places in France and England under circumstances similar to those in the valley of the Somme. In England they have been found along almost all the rivers in the southern and south-eastern part. One class of discoveries there gives us new ideas as to the extent of time that has passed since they were deposited. That is where they occur in gravel beds having no connection with the present system of rivers. In one case the gravel forms a hill fifteen feet high, situated in the midst of a swampy district, surrounded on all sides by low, flat surfaces. Several such instances could be given; but, in all such cases, we can not doubt that, somewhere near, there once rolled the waters of an ancient river, that man once hunted along its banks, and that, owing to some natural cause, the waters forsook their ancient bed--and that since then, in the slow course of ages, the action of running water has removed so much of the 89 surface of the land near there, that we can not guess at its ancient configuration: we only know, from scattered patches of gravel, that we are standing on the banks of an ancient water-course. One instance, illustrative of the great change that has come over the surface features of the country, demanding for their accomplishment a great lapse of time, is furnished by the Isle of Wight. That island is now separated from the mainland by a narrow channel, called the South Hampton Water, or the Solent Sea. It is now known that this is nothing but an old river channel, in which the sea has usurped the place of the river. The coast is a river embankment, with the usual accompaniments of gravel beds, flint implements, and fresh water shells. On the shores of the island we find the opposite bank of the old river. A very great change must have taken place in the surface features before the sea could have rolled in and cut off the Isle of Wight from the mainland. In speaking of the length of time demanded for this change, Dr. Evans says: "Who can fully understand how immeasurably remote was the epoch when what is now that vast bay was high and dry land, and a long range of
