68 LAMPLUGH : NOTES ON THE WHITE CHALK OF YORKSHIRE. 
side of the promontory, and by a consideration of the evidence 
afforded by the inland sections in the vicinity of Bridlington. 
The full account of these measurements is, for convenience of 
reference, given below (see Appendix, p. 80). This record gives 
the details of an unbroken sequence of strata from the base of 
the cliff below Sewerby Park, where the mensuration of each 
individual layer first becomes practicable, eastward for 1,400 yards, 
to the vicinity of the Danes Dike ravine. In this distance a 
thickness of 205 feet of Flintless Chalk is traversed. There 
is, however, for about 400 yards to the westward of the measured 
section, a cliff of Chalk composed of higher beds ; but these are so 
much disturbed by glacial action and so greatly obscured by slips 
that it has not been found possible to measure them in detail. I 
think that we should allow, at least, an additional 35 feet for these, 
thus bringing up the total thickness seen in the cliff to the westward 
of Danes Dike to 240 feet. This somewhat exceeds the result 
obtained by Blake, who places the depth to this point at 192 feet. 
But it is almost certain, on both stratigraphical and palseonto- 
logical considerations, that the Chalk of the rising ground south-west 
of Bridlington comprises a considerable thickness of higher beds than 
the uppermost layers represented in the cliff-sections ; and though 
the depth of these higher strata has not yet been accurately deter- 
mined, I believe that they cannot fall below 100 feet, and not impro- 
bably are much thicker. 
The valley at Danes Dike causes a gap in the cliff-section which 
is somewhat difficult to span. There is much disturbance of the 
bedding, both in the low- water scars and in the cliff on the western 
side of the ravine ; and though this has undoubtedly been accentu- 
ated by superficial crushing in glacial times, it seems to be essentially 
a structure of more ancient date. It probably denotes the presence 
of a fault in this locality, of more considerable value than the 
numerous minor breaks presently to be discussed which almost 
everywhere in these sections intersect the Chalk. That there is not, 
at any rate, a doAvnthrow to the eastward sufficient to cause a 
repetition of the strata, is established by the presence of the well- 
marked band containing abundant remains of Marsupites oiiiatu^ 
