Page:The Geologist, volume 5.djvu/174

146 between the different tribes which at that period inhabited France. These premises he merely puts forward, reserving for a future occasion the discussion which alone can establish their correctness. What he desires to do now is to show that the field of discovery as to the antiquity of the human race is at least open, and that this question, already so wide from the little we as yet know, seems likely to be spread still wider by such discoveries as that of which he gives the details.

An object "incontestably fashioned by the hand of man" has been found at a depth of 75 mètres from the soil, in a perfectly virgin bed of the lignites or "cendres noires" at Laon, the geological age of which goes back, as is known, to the earliest times of the Paris basin deposits. Not but that objects of modern production have been found in these very beds, and he cites particularly a flint "hache," which was found fourteen years since at 25 feet under ground, in the middle even of the lignites quarried near the village of Lille, canton of Fère, department of Aisne. But these facts, besides being so rare, are capable, in general, of being explained by accidental causes of entombment, the lignites of the Laonnois and of the Soissonois lying ordinarily at the surface or only being covered by foreign deposits of no great thickness. This is not the case with the ash-bed of Montaigu, near Laon, whence the object in question comes. "The exceptional conditions of the bedding where it was found is precisely that which gives to this discovery a special interest, and perhaps a considerable value; and it is thus necessary to give here a slightly detailed description, and to make known the method of quarrying."

"The lignites worked for agricultural purposes near the village of Montaigu, four leagues north-east of Laon, occupy the foot of a Tertiary hill, constituted at its base of clays, amongst which these lignites are intercalated; in the middle, of thick masses of sand, enclosing some beds of shells; and at the summit by newer clays superposed on thick beds of hard rock—the Calcaire grossier of geologists, which form the crown of the hill. The 'ash-bed' is quarried by means of subterranean galleries, which extend in different directions under the hill—the principal one being driven into the centre of it for a considerable distance, its extremity not being less than 600 mètres from the point where it opens on the valley. This bed is about 2⋅30 mètres thick, and is covered by another bed of marly and sandy clay, full of fossil shells peculiar to that age—Cyrena cuneiformis, Ostrea bellovacina, etc., and which serves for the roof or ceiling of the quarry. This roof is sustained by means of wooden shores placed under and across as the gallery extends; the head only of the gallery being left free for the work of extraction. The 'ash-bed,' attacked at the foot, falls down into the space called the 'chamber,' detaching itself cleanly from the roof alluded to; and then the 'ashes' are put into small waggons running on an iron tramway. These 'waggons' in their turn are pushed by men out of the quarry, and the 'ash' is discharged and made into a heap for burning before being sold for agriculture. In the month of August last year (1861) the workmen employed at the end of the principal gallery, in throwing down a block of 'ashes,' observed with surprise an object detach itself and roll to some distance. Struck with this incident, such as had never before happened to them, they hastened to search for it, and found a ball of moderate dimensions. But their astonishment was increased when on examining it they thought they recognized it as the work of man's hand. They looked then to see exactly what place in strata it had occupied, and they are able to state that it did not come from the interior of the 'ash,' but that it was imbedded at its point of contact with the roof of the quarry, where it had left its impression indented.