244 
LAMPLUGH : CHALK OF FLAMBRO' IIEAD. 
increase in abundance on the beach, and again take their place in 
the cliff in force. 
Beckoning from the data thus supplied, I should estimate 
the amount of downthrow to the north at about 80 feet. 
As seen on the beach the direction of the fault is N.E. and S. W. 
Here also the tilted flint-bearing- beds on the southern side are 
seen to abut against well-nigh level flintless strata on the north. 
For some distance on each side of the fault, however, there is no 
very regular dip. 
I think it more than probable, chiefly on paloeontological 
evidence, that a fault also exists in the chalk at Danes' Dyke, a 
deep valley between Flambro' Head and Bridlington. In this 
case the downthrow appears to be to the south ; but as yet I have 
attempted no estimate of its extent. 
Before concluding, I would draw attention to some note- 
worthy facts in connexion with the drift which, as usual, caps the 
chalk above Selwick Bay. 
This drift, which consists of several beds, or bands, of 
Boulder Clay (or Till) with gravel partings, has at its base, a 
curious and interesting layer of Blue Clay, which, upon examina- 
tion, proves to have been chiefly derived fron the Neocomian and 
Kimmeridge clays, for which the nearest known locality is in the 
vale of Pickering, over seven miles distant. 
This blue clay clearly shews its origin by plentiful fragments 
of such characteristic fossils as Belemnites jacidum of the Middle 
and Lower Neocomian ; B. lateralis, and Exogyra sinuata, of the 
Lower Neocomian, etc., along with nodules of weathered pyrites, 
from the L'pper Neocomian, and with a few small red chalk 
uebbles. 
Traces of this bed are first seen below the Fog-gun house, 
and may be followed thence northward to the north side of Sel- 
wicks, a distance of several hundred yards ; it may extend much 
further, though not seen in cliff section. In places it consists of 
pure Neocomian Clay, simply removed and in the condition of a 
boulder ; but more often it has had a few red and white chalk 
