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* ON THE LARGER BOULDERS OF FLAMBOROUGH HEAD AND OTHER PARTS 
OF THE YORKSHIRE COAST. PART IV. f BY G. W. LAMPLUGH. 
My investigation of the boulders of Flamborough Head, begun 
in 1887, has now been continued on that part of the shore which lies 
between the South Sea Landing and the extremity of the headland. 
I do not know of any other part of the Yorkshire Coast where 
erratic blocks are so numerous as they are on the beach for the last 
half-mile on the south side of the promontory. The total number 
within this space cannot be less than four thousand, and they lie so 
closely that for some distance it is possible to step from one to 
another. 
Some are of large size (see examples in Appendix), and the 
average diameter is probably about two feet. They seem to have 
been derived chiefly from a coarse morainic gravel which partly fills 
a buried pre-glacial chalk valley in the adjoining cliff, but their 
retention and accumulation at this place is no doubt owing to its 
being sheltered from the heavy northerly gales which break with 
terrific force on the other side of the promontory, while here the sea 
rarely runs high enough to shift blocks so heavy as these. 
I estimate that the total number of erratic blocks over one foot 
in diameter lying on the shore between South Sea Landing and the 
Lighthouse must exceed six thousand, and to this number about 
another thousand must be added if those are included which have 
been collected and heaped up to form a rade break-water at the 
South Landing. It would scarcely be profitable to catalogue so 
large a number as this even if it were possible, and I have there- 
fore contented myself with examining eight hundred, chosen in 
different parts of the area, while of the rest I made a cursory 
survey which showed me that there is very little variation in the 
proportion of the various rocks among them, and therefore that, for 
* An abstract of this paper was read at the Leeds meeting of the British 
Association. 
f See Proc. Yorksh. Geol. and Polytec. Soc, vol. ix., pt. iii., p. 339, for parti., 
and vol. xi., pt. ii., p. 231, for parts ii. and iii. of this paper. 
