﻿Correspondence — Mr. Senry Norton. 287 



to their action? .... Now among the debris which have filled 

 these cavities . . . bones of the great mammalia of the Quaternary 

 period have been found." (Elephant.) 



There is a difference of opinion as to the date of the excavation : 

 M. Eoyer contending that it was before, and M. Belgrand that 

 it was after, the excavation of the valleys; but both agree in 

 attributing these pits to the action of a vast quantity of water, 

 whether produced by a diluvial cataclysm, or else by the incessant rains 

 of the Pluvial period in which they both believe. The description 

 immediately suggested to me a strong resemblance to " Grimes 

 Graves," near Brandon, an account of which will be found in the 

 Journal of the Ethnological Society of London, New Series, 

 vol. ii. p. 419, in an article on the opening of Grimes Graves, in 

 Norfolk, by the Eev. William Greenwell, M.A., F.S.A. 



Beyond all question Grimes Graves were excavated by the manu- 

 facturers of flint implements ; and they were sunk to a depth of 30 

 or 40 feet in order to reach a layer of flint especially suited to their 

 purpose. There are some circumstances mentioned by M. Eoyer in 

 which his pits agree with these : their great number, the subter- 

 ranean communication one with another, and lastly the form, so far 

 as it is suggested by the French words ' puit' and ' gouffre,' both 

 applied to these pits. M. Eoyer speaks of " capricious forms," which 

 seems to betray the fact, that he is puzzled to know how those vast 

 waters could have done it so regularly (?). The depth of "some of 

 them," 30 to 40 metres, is indeed somewhat staggering, being three 

 times the depth of the Brandon pits, and the rock is not Chalk, 

 but corresponds in age to our Portland. M. Contejean, in his 

 " Elements de Geologie et de Paleontologie," p. 620, describes the 

 " terrain jurassique " as consisting in thick argillaceous and 

 calcareous beds (massifs), often irregularly alternating, and as 

 including, at various levels, ferruginous layers, and layers of flint 

 nodules. And at p. 426 he says, siliceous nodules (rognons) exist in 

 all sedimentary deposits, but especially in the Jura limestone and 

 in chalk. What is the precise nature of the Upper Oolite in 

 Burgundy and Champagne my library does not give me the means 

 of knowing. Burat only remarks that it does not present such 

 marked forms (due to the outcrop of limestone) as the middle and 

 lower Oolite ; the argillaceous part (assise) at the base is but little 

 developed ; the greyish or yellowish-grey calcareous beds (calcaires) 

 of the upper part (assise), which are found at first in isolated 

 outliers, on the summits of the middle stage (etage moyen), end by 

 forming, at the foot of those summits, an undulating surface of hills 

 with more or less gentle slopes, with altitudes of not more than 150 

 and 200 metres, the inclines and escarpments of which are less 

 conspicuous. Among localities where the beds may be studied, he 

 mentions Bar-le-duc, Bar-sur-Seine, and Auxerre ; and says that in 

 the Portland beds the limestone is too much divided to be quarried, 

 and forms stony plateaux (p. 440). It does not appear from these 

 authorities that any insuperable impediment exists to such pits 

 having been sunk by man ; and the suggestion is countenanced by 



