644 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 22, 
Lower Boulder-clay has been described by two observers as re- 
sembling the Upper Till at great elevations on the Penine Chain; 
but on further examination, it may possibly be found that the clay 
in these instances belongs to the upper division. I myself have 
never found any marine Lower Boulder-clay above an elevation of 
one hundred and fifty feet ; and I believe that the glacial sea, in the 
Lancashire lowlands, had only a depth of about twenty-five fathoms 
at the close of the period of its deposition. 
Fine sections of this Boulder-clay are exhibited in the cliffs of the 
Ribble, above Preston, especially at Red Scar and Balderstone, at 
which latter place the section was first described* by Prof. E. Hull 
in 1867; and I had the pleasure of showing it to Mr. Mackintosh 
in the spring of last year. 
Middle Drift—The sand and gravel of the Middle Drift rests 
upon a slightly undulating inclined plane of Lower Boulder-clay, 
dipping from the hills of the Penine Chain towards the valley of the 
Mersey at Manchester, and towards the sea in the country to the 
west—no doubt owing to its being a plane of deposition on a 
sloping sea-bottom, as suggested by Prof. Ramsay to Mr. Hull, to 
account for a similar phenomenon in the Manchester district ,— these 
hills, like the mountains of the Lake-district, forming islands in the 
Lower Boulder-clay sea. 
The Middle-drift sand is well seen in the cliff at Codling Gap, 
near Egremont, in Wirral, where about 70 feet of Lower Boulder- 
clay occurs between it and the underlying pebble-beds of the Bunter 
Sandstone, with about the same thickness of Upper Till above ; and 
at the side of it the sand is much current-bedded and is extremely 
fine-grained, has almost to resemble the Fox-mould of the south-west 
of England; it contains a fair number of pebbles, all of which are 
rounded, but none scratched. ‘These generally lie in the lines of 
current-bedding, as is the case with the pebbles in the Triassic 
Pebble-beds of the district. The sand in this section is only about 
20 feet in thickness, and may almost be said to be intercalated in 
the Boulder-clay. The rock surface here is a little below high- 
water mark, extending under the drift to an early, or preglacial cliff, 
probably about 600 yards inland at Egremont. This approaches the 
river and the sea at New Brighton, and forms the existing line of sea- 
cliff there, culminating in the well known picturesque cliff called the 
“ Red Noses,” soon after which the rock is lost sight of under a range 
of sand dunes. 
In the Lower. Boulder-clay of Codling Gap I found a shell of 
Turritella communis ; and Mr. Morton records the occurrence of that 
shell and Mya truncata in the Lower Boulder-clay of Liverpoolf. 
On crossing the river Mersey from Liverpool to Seacombe, and 
ascending the hill upon which the village of Liscard is built, the 
peninsula of Wirral is seen to be divided in two by a deep narrow 
gorge, at the bottom of which flows Wallasey Pool. This river, now 
* Trans. Man. Lit. & Phil. Soe. vol. vi. 3rd series. 
+ Ibid. vol. ii, 3rd series. 
t Geology of Liverpool, p. 15. 
