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ON THE LARGER BOULDERS OF FLAMBOROUGH HEAD. PARTS II. AND III. 
BY G. W. LAMPLUGH. 
The object of this paper is to give an enunieratioii of the 
boulders in the Danes Dyke Valle)^ and on the shore eastward to 
South Sea Landing ; with a discussion of their origin, and a com- 
parison of them with those found near Withernsea. 
In pursuance of an investigation into the nature of the larger 
boulders of Flamborough Head, commenced two years ago, I have 
examined and catalogued those which lie in the ravine of Danes 
Dyke, and also those on the shore between Danes Dyke and South 
Sea Landing. The former list becomes Part IL of the series ; the 
the latter, Part III. 
PART II. THE DANES DYKE RAVINE. 
The clilf sections at Danes Dyke show that at this part of the 
headland there existed in pre-glacial times a deep valley in the chalk, 
which was afterwards filled in and obliterated by the accumulations 
of the glacial period. It has since, however, been partly re-excavated 
by a small stream, arising from the surface drainage, which, though it 
nins only in winter and stormy weather, has sufficed to cut its way down 
through the easy-removable infilling of clays and gravels, to the old 
chalk-floor. The current of this stream is only strong enough to carry 
the lighter stones, so that a residuum of larger blocks has accumulated 
in its bed, and lie there perishing slowly under the weather. 
I have examined these boulders, and, after rejecting all whose 
greatest diameter does not exceed one foot, found 142 erratics between 
the mouth of the valley and the Flamborough and Bridlington high 
road where the valley practically terminates. Doubtless many more 
lay hidden under the gTavel which in places cumbers the stream-bed, 
but these were all that were visible at the time of my survey. 
The chief importance of the list is that there is in this case no 
probability of the boulders having been much disturbed by man, as 
the banks of the ravine are generally steep and inaccessible ; and we 
may, therefore, find in it a test for the trustworthiness of the lists 
compiled upon the shore. 
