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Rh particle of wood having perished, without leaving even a stain behind. Passing down the hill towards the river, all these strata are seen to die out, and we find ourselves on the bare chalk; but again at a lower level occurs another bed of gravel, resembling the first, and capped also by the bed of brick earth which is generally known as loess.

These strata, therefore, are witnesses; but of what? Are they older ihan the valley, or the valley than they? are they the result of causes still in operation, or the offspring of cataclysms now, happily, at an end. According to the accomplished writer in Blackwood their testimony is but unsatisfactory. Examined they tell one tale; cross-examined they contradict themselves, until the jury falls back hopelessly on a verdict of "not proven."

If, indeed, we can show that the present river, somewhat swollen perhaps, owing to the greater extension of forests in ancient times, and by an alteration of climate, has excavated the present valley, and produced the strata above enumerated; then "the suggestion of an antiquity for the human family so remote as is here implied, in the length of ages required by the gentle rivers and small streams of eastern France to erode its whole plain to the depths at which they now flow, acquires, it must be confessed, a fascinating grandeur, when, by similitude of feature and geology, we extend the hypothesis to the whole north-west frontiers of the continent, and assume, that from the estuary of the Seine to the eastern shores of the Baltic, every internal feature of valley, dale and ravine—in short, the entire intaglio of the surface—has been moulded by running waters, since the advent of the human race."

But, on the other hand, it has been maintained that the pliant facts may be read as "expressions of violent and sudden mutations, only compatible with altogether briefer periods." The argument of the Paroxysmist, I still quote from Blackwood, would probably be something like the following:—

"Assuming the pre-existing relief, or excavation rather, of the surface to have approximated to that now prevailing, he will account for the gravel by supposing a sudden rocking movement of the lands and the bottom of the sea of the nature of an earthquake, or a succession of them, to have launched a portion of the temporarily uplifted waters upon the surface of the land."

Having thus heard the arguments of Counsel, let us now call the witnesses to speak for themselves.

Taking the section at St. Acheul and commencing at the bottom, we have first of all the subangular gravel throughout which, though especially at the lower part, the flint implements occur.

A similar bed may be found here and there all along the valley of the Somme; at St. Acheul it is about 90 ft. above the present river level; at Moulin Quignon, near Abbeville, the same; while at Picquigny and at Cæsar's Camp near Liercourt, we found it at a height of 150 feet. Though only occurring in places, this gravel is so