PHOTOGRAPH. 
105 
feet, but as we follow its course westward, it resumes its regularity, 
and rises somewhat swiftly to 250 feet, and then more slowly, till 
at Speeton, about five miles from Thornwick Bay, where the coast- 
line swerves northward and thus marks out the headland, the total 
height of the c!iff is 444 feet. 
The sudden change in the character of the coast at the easter- 
most point is not difficult to explain, and is due to more causes than 
one. 
In the first place, the force of the sea is far greater on the 
exposed north than on the sheltered south side of the headland, 
and a violent tide-course also strikes it and is deflected eastward. 
Then the upper flintless chalk,* which forms the clifis between 
Bridlington and Flamborough, is soft and shattered, and yields 
readily to the waves all along the line ; but at the headland, flints 
put in an appearance, and the chalk becomes extremely hard and 
unyielding, and withstands the attack of the sea so well, that 
differences of resisting power have time to produce great results, 
and all the weak points, along joints, or where the beds are crump- 
led or shattered, are carved out. 
There is still another cause. It will be noticed in the ])hotograph 
that the old chalk surface below the drifts slopes inland, so that 
while the chalk is 90 or 100 feet thick on the headland, it is not 
more than 8 or 10 feet in the recess, pai't of this decrease, however, 
being due to the rise of the beach. This is really the northern slope 
of a valley which, in pre-glacial times, has run almost parallel with, 
and at no great distance from, the present cliff"-line. This valley, 
which has been filled with drift and nearly obliterated during the 
Glacial Period, follows the northei-n coast-line of The Head to its 
extremity, and there runs out, being cut across where the cliff" 
swerves south-west for Bridlington. Lateral feeders seem to have 
run into it from the north-east ; indicating a wide extension of land 
in that direction. 
This old valley causes some of the finest features of the coast. 
* This upper chalk contains a fair number of fossils, chiefly sponges. 
