172 SHEPPARD AND STATHER : GLACIAL DRIFTS OF HOLDERNESS. 
been carefully sketched, and in this way particulars of the 
structure of the entire hill have been secured. 
Fig. 1 illustrates the easternmost section seen, and is 
entirely in boulder clay. Fig. 2 represents the same face when 
cut back 50 yards, and shows round tongue-like masses of the 
shelly gravel appearing at the base of the cutting from beneath 
the boulder clay. Fig. 3 represents the section parallel to the 
former, but still further west, and shows the shelly sand and 
gravel taking the place of the boulder clay almost throughout 
the section. Four of these sketches are given on Plate XXL, 
and illustrate parallel sections right across the easte'rn flank of 
the hill from north to south, and about 50 yards apart. 
The present section (Fig. 4, PI. XXL and PI. XXII.) 
exhibits 46 ft. of shelly gravel and fine sand in the centre, 
with no boulder clay above, though the latter flanks the deposit 
at both ends. The cutting is here approaching the crown of 
the hill, from which the boulder clay has been sub-aerially 
denuded. 
At the present time the section is 1,300 ft. long and 
46 ft. high in the centre, from which point it gradually slopes 
to the north and south. 
A detailed examination of the sections as they were exposed 
showed conclusively that the core of the hill consisted of a conical 
gravel mound, similar to those at Kelk and other places nearer 
Bridlington, which had been over- ridden, kneaded out, and 
generally disturbed (PI. XXlll.) by an advance of the ice, which 
plastered the sides with boulder clay and filled in any 
irregularities of the surface with the same material. 
The direction of this movement was obviously from the 
north, from which point also came the water which gave 
a current-bedded structure to parts of the gravel. 
The sheUy gravel occurs in a large mass forming the centre 
of the hill, but parts of this have been torn away, and, as in 
the case of the boulder clay, have been incorporated with the 
coarser gravelly material. Thus in more than one place an 
irregular seam consisting almost entirely of shell-fragments may 
