The implements of man are relatively more common, seventeen chipped flints having been found.
Thick, and formed of a core of rough rubble cemented together with mortar (containing much coarse gravel) of extraordinary hardness and tenacity, and a facing for the most part of stone - Kentish rag, freestone or ironstone - but occasionally of flints; about 2 ft.
By his collection of flints Boucher de Perthes had been the first to attempt to establish the existence of man in remote ages; but it had been objected that if the flints were indeed the work of man, human remains would have been found in association with them.
The contemporaneity of these structures has been demonstrated by the identity of the pottery and other objects discovered in them, including some remarkable steatopygic figures in stone, and it is clear that they belong to the neolithic period, numerous flints, but no metal, having been found.
The Senonian series is represented by the White Limestone, a hardened chalk with flints, which is often glauconitic and conglomeratic at the base.