[Illustration: Fig. 47.--Section of the cliff on the east side of South Sea Landing, Flamborough Head. Scale, 120 feet to 1 inch; length of section 290 yards; average height, 125 feet. (See above map of moraine between Speeton and Flamborough.) Explanation.--_4._ Brownish boulder-clay, a band of pebbles; _4a_, in places about seven feet from top. _3._ Washed gravel, with thin sand-seams, well-bedded, pebbles chiefly erratics. _2._ "Basement" boulder-clay, with many included patches of sand, gravel, and silt; _2a_, at _B_, one of these _2b_ contain shells. _1b_. Sand and silt, overlying and in places interbedded with _1_. _1._ Rubble of angular and subangular chalk-blocks and gravel, with occasional erratic, passes partly into chalky boulder-clay, _1a_. _x_. White chalk, without flints, surface much shaken.] "At Flamborough Head shelly drift attains an altitude of 400 feet, but half a mile from the coast the country is practically driftless even at lower levels. The Yorkshire Wolds were not submerged. On the western flanks of the wolds drift comes in at about 100 to 150 feet, and persists, probably, under the post-glacial warp, from which it again protrudes on the western side of the valley of the Ouse, and however the drift between there and the Pennine water-shed may be interpreted, it shows not a sign of marine origin; but, even granting that it did, we find that it does not reach within a thousand feet of the water-shed. When the water-shed is crossed, however, abundant glacial deposits are met with which are not to be differentiated from others at slightly lower levels which contain shells. [Illustration: Fig. 48.--Enlarged section of the shelly sand and surrounding clay at _B_ in preceding figure. Scale, 4 feet to 1 inch. Explanation.--_2._ "Basement" boulder-clay. _2a_. Pure compact blue and brown clay of aqueous origin, bedding contorted and nearly obliterated, but the mass is cut up by shearing planes. _2b_. Irregular seam, and scattered streaks, of greenish-yellow sand with many marine shells. _2c_. Patch of pale-yellow sand, different from _2b_, without trace of fossils.]