26 
BLAKE: EAST YORKSHIRE. 
followed by Middle and Upper Neocomian, and we thus learn 
that it took the whole of that period to entirely strip the 
surface of its covering. While, however, the rivers that led 
eastward were charged with argillaceous matter, those that 
ran southward, draining the southern axis in that direction, 
may have eaten through to the lower oolitic deposits, and 
have contributed in some degree to the calcareous rocks which 
are now the ironstones of the Middle Neocomian or Tealby 
series of Lincolnshire, and which probably extended at one 
time into Yorkshire. 
At the end of the Neocomian period, East Yorkshire 
ceased to be local, and became for upper cretaceous deposits 
part of a wider area. The northern moorlands may have 
still remained above the sea when depression once more set 
in, as there is no proof that the chalk was ever there, and 
much against its having been ; but the southern axis was 
submerged, and disappeared from importance for a time, 
opening the area from the vale of Pickering southwards into 
the great sea which stretched eastwards to North-west 
Germany and southwards as far as the Wash. This sea was 
shallow, and hardly any deposit was formed in it, and it was 
separated from the southern seas by a barrier like that which 
once separated Yorkshire. While to the south the denudation 
of the Kimmeridge clay — interrupted for a while by the 
configuration of the country, which led first to the Wealden 
deposits, and then to Lower Greensand, all in comparatively 
shallow water — was continuing, and Gault was being formed, 
the more northern sea was at rest, and only accumulating a 
few feet of red chalk, whose colour may be due to the deposit 
of various ferruginous compounds during its very slow 
formation. When this red chalk first commenced seems to 
be a disputed point ; nor can it be absolutely decided. The 
area of its deposit was itself formed after the last of the 
Neocomian beds, as we learn at Speeton ; but how soon after, 
