COLE : PHYSICAL GEOGKAPHY OF Tf!E EAST EIDING. 121 
mass than in the lower flint-bearing- beds, as ascertained by Mr. J. 
R. Mortimer. Chalk is extremely porous and the rainfall sinks 
rapidly through the mass : at the same time the heat of the sun draws 
the moisture to the surface, so that even in dry seasons there is far 
more moisture for the delicate fibres than in many other soils. 
The Chalk cliffs at Bempton, Buckton, and Flamborough present 
some of the finest coast scenery in England. During the breeding 
season they are covered with innumerable hosts of sea-birds, who 
think it the height of felicity to scream and squabble at the top of 
their voices. It has one good effect : in a fog you know where you 
are ; which is encouraging. It would be a good thing to extend 
the close time for shooting anotlier month, as now manj^ a poor 
young bird is starved to death ; besides, the birds might then all 
get away, and it would encourage trade to fire at bottles instead of 
birds. They would be just as bad to hit bobbing away on the 
■waves, which is all the sportsmen want. 
The East-Riding, in common with the North of England, has, 
with perhaps a temporary submergence during the Glacial age, been 
dry land thoughout the Tertiary Period. During this vast period the 
whole of the Nummulitic Limestone which extends from the Pyrenees 
to the Himalaya, and is many thousand feet thick, was being deposited 
beneath the sea. But no trace of any later rock than the Chalk 
occurs in the East-Riding till we come to the Ice Age. Then an 
enormous glacier, originating in the mountains of Scandinavia, spread 
itself over the present area of the North Sea, and pushed before it 
the mass of Boulder Clay, which forms the surface soil of Holderness, 
to a depth, at Hornsea, of upwards of 130ft, and which even caps 
the tops of the Chalk cliffs at Bempton. 
A stream of ice coming down the East Coast from Scotland, as 
well as from the high grounds of the Pennine range, overpowered 
by its mighty neighbour from the north-east, pressed against the 
Chalk Wolds, and covered all Holderness with a mantle of Boulder 
Clay ; not once, or twice, but man3^ times : so that this wide district 
presents a character of its own, scarcely to be met with elsewhere. 
The conformation of the ground lends its aid, as the lowest part 
of the area is not on the coast, but, landwards, towards the centre of 
