44 
DAVIS : CONTOKTIONS AT FLAMBOEOUGH. 
seen from the sea ; the chalk forms alternate promontories and bays, 
the former are carved by the never-ceasing action of the tides, into 
innumerable caverns and fissures. As the boat proceeds along* 
the shore the cliffs gradually become higher until the maximum of 
446 feet is reached. Myriads of guillemots and puffins occupy the 
ledges and crevices of the rocks, on which they lay their eggs and 
rear their young. Their swooping, circling flight, and shrill cry 
renders both the air and sea a source of interest to the naturalist. 
Extending seawards from the base of the cliff great boulders 
cover the beach and afford evidence of the power of the waves, in 
combination with frost, to break up even the mightiest cliffs and the 
hardest rocks. The boulders make it difficult to land from a boat, 
and the fucoid growth covering their surfaces do not add to the 
pleasure of scrambling over them to attain the narrow strip of sandy 
beach which extends along the immediate fi'ont of this cliff. It is 
interesting to observe the emergence of a subterranean stream at the 
right extremity of the section, a good example of the underground 
Mirainage of the chalk wolds. 
The chalk in the S.E. portion of Yorkshire, extends in a great 
semi-circle from Flamborough, first westwards and then southwards 
as far as the Ilumber at Ferriby and Hessle. It forms an elevated 
and undulating series of hills separated by deep ramifying valleys, 
along the bottom of which streams run only at intervals after heavy 
rains, and when the chalk is charged with a larger quantity of water 
than can be conveyed to the sea by the ordinary underground 
channels. 
The chalk of the Yorkshire Wolds is usually of a hard and 
more or less flaggy nature, the la^^ers separated by a fine unctuous 
clay resembling fullers earth, in this respect it differs from the chalk 
of the south which is thick-bedded and much softer. The lower beds 
of the chalk, as may be seen in the cliffs of Buckden and Bempton, 
abound in layers of nodular flint, whilst those higher in the series 
forming the cliffs further south are almost devoid of flints. Mr, Fox 
Strangways has pointed out that the occurrence or otherwise of flint 
has a marked effect in the character of the soil above the chalk ; 
the northern district of the wolds westwards from Hunmanby 
