LAMPLUGH : GLACIAL SECTIONS. 
391 
1 Hessle Clay ' of Messrs. Wood and Rome, which, it will be 
noticed, is not otherwise seen in these sections. I do not purpose 
entering into this question on this occasion, as the drainage works 
now being carried on in the town will yield fuller evidence on 
this point. 
The lower division of the clay (36) is undisturbed and seems 
to pass downwards into sand ; at any rate, there is a few inches of 
what looks to me like finely-bedded clay — different from the flaky 
look of the top at C in section 1 — between true unstratified bould- 
er-clay and the seam of sand which overlies the laminated clay. 
This division in the Purple Clay and the intermediate gravel — 
which however completely changes its character — may be traced 
with difficulty as the cliff is much obscured with talus, for about a 
mile northward, to the beginning of the chalk. Beyond that, 
though the division seems to be continuous, che mediate beds are 
very intermittent. In going northward from section 2, the cliff 
rises suddenly ( Potter's Hill ) ; and beyond, the upper gravel, 
which swells out to a thickness of 8 to 16 feet is evenly bedded 
and overlies the upper clay band, (also greatly increased in thick- 
ness) with very little irregularity for over a mile, when the top of 
the clay is again somewhat deranged. It has been suggested that 
this thick and regular gravel — the 1 Sewerby Gravel ' — may be of 
different age from the low level gravel of these sections, and that 
this may be a re-arranged valley gravel. On this point the evi- 
dence is not conclusive. 
South of the point where the middle gravel (2a) begins, there 
is, for a short distance, a series of lines in the boulder clay ; 
and these, as they occasionally contain a few leaves of laminated 
clay, seem to be bedding planes. 
The Laminated Clay (4), the next member of the series, exists 
in Section No. 1 only in detached patches in the base of the Pur- 
ple Clay near A ; but in Section No. 2 it forms the base of the 
cliff and reaches some way down the beach, having a thickness 
of about 8 feet. Above it, there is an intermittent seam of fine 
