MEN OF THE loo-FOOT TERRACE 163 
series of deposits is named here the " Strepyan," because 
the implements found in it are of the type which M. 
Rutot discovered and named in the corresponding valley 
deposits of Belgium — especially at Strepy, a village to the 
west of Charleroi, lying within the watershed of . the 
Meuse. The Strepyan series of deposits consist of a 
deep bed of gravel (the "lower" gravel), made up of 
several layers ; over the gravel a deposit of loam (" lower " 
loam) (see fig. 57). The gravel was laid down in the bed 
of the Thames when the river was flowing at a level of 
about 100 feet above its present bed. The Strepyan series 
Soil 
upper gravel 
:^ UPPER LOAM 
BEDDED SANDS 
MIDDLE GRAVEL 
LOWER LOAM 
LOWER GRAVEL 
SAND ON Chalk 
Fig. 57. — Diagram showing the various deposits of the lOO-foot terrace of the 
Thames valley at Swanscombe, modified from Mr Dewey's sections. 
ends with a stratum of loam — a deposit formed in still 
water in times of flood. The second series of deposits, 
lying over the Strepyan, and therefore more recent, 
yielded, in its basal bed of gravel, the same kind of flint 
implement as occurs in the ancient deposits at Chelles, in 
the valley of the Marne, about eight miles to the east of 
Paris. At the time, then, when the second series of 
deposits in the 100-foot terrace began to be deposited, 
culture or civilisation of the natives of the Thames valley 
had entered the " Chellean " phase or stage. In the sands 
and loam, the later deposits of the second series, another 
culture appears — the older Acheulean, usually known as 
St Acheul I. The third and most recent series of the 
100-foot terrace again commences with a stratum of 
