Rk. M. Deeley—The Glacial Succession. 30 
unlike those which had been laid down by the earlier glaciers. I 
refer to the spreading of easterly and southerly rocks, such as chalk, 
flints, and Lias limestone and fossils over the older formations to 
the west and north-west, by an ice-flow which moved in a direction 
contrary to or across that of previous or subsequent ice movements. 
In the Midlands of England the Older Pleistocene series consists 
of two thick deposits of tough Boulder-clay, separated from each 
other by a thick, false-bedded bed of sand or gravel. These deposits 
are not local, but on the contrary have been found retaining their 
lithological characteristics at such widely separated points as Gelston 
near Grantham, Leicester, Nottingham, Burton, and Ashbourne. 
The boulders are mainly of Pennine origin, but there are a few 
more distant erratics. Flint and chalk are quite absent, although 
the deposits occur within a few miles of the Cretaceous escarpment. 
It has been suggested that these Older Pleistocene deposits were 
formed when the local glaciers entered the lowlands, and that the 
easterly rocks were thrust over them by the brushing aside of the 
local ice by the pressure of a great Scandinavian ice-flow. But 
the deposits themselves when examined in detail do not seem to 
support this view, for the line of demarcation between the two is 
quite sharp, and when the succession is anything like complete the 
Harly and Middle Pleistocene Boulder-clays are separated by sands 
which clearly indicate open water. It only seems possible to account 
for this absence of local glaciers when the Scandinavian ice advanced 
over this country, on the assumption that it occurred during a period 
of submergence. It must be admitted that the opposition, just now, 
to such a view is very strong; an opposition, I think, based on very 
inadequate grounds. 
During Older Pleistocene times the mountains of Great Britain 
stood well out of the sea, and as the climate became more and more 
severe the glaciers radiated from the hills, spread over the partially 
submerged low-lands, and deposited the great beds of non-flinty, 
silty, Boulder-clays, tills, and sands. In these silty clays, deposited 
long distances from the hills, the proportion of well striated stones 
is very large, indeed much larger than in the moraines formed in 
the mountain valleys. This arises from the fact that by the time 
the ice had reached the Midlands the glaciers in the hills had become 
so thick that very few cliffs were sufficiently high to shed stones on 
their upper surfaces; the transported rocks being mainly derived 
from the bed of the ice. It is quite possible that the British ice 
passed into the German Ocean and became confluent with the 
Scandinavian ice at this particular epoch; but, however this may be, 
it is quite certain that the Continental ice was unable to override 
what is now the Trent Basin. 
At the close of the Older Pleistocene epoch the climate again 
became warmer, but in the succeeding Middle Pleistocene epoch 
cold conditions again supervened, but this time accompanied by a 
submergence. During this epoch it is possible the Moeltryfaen, 
Macclesfield, Gloppa, and Wicklow high-level shell gravels were 
formed. Owing to this submergence there seems to have been an 
DECADE III.—VOL. X.—NO. I. 3 
