’ 
COOKE: GLACIAL DEPOSITS OF CLEETHORPES AND DISTRICT. 279 
represent the Hessle and the Purple clays respectively, and one of 
the most conspicuous features that serves to differentiate the one 
from the other is the extremely decomposed state in which the chalk 
rubble is always found in the upper of the two. This upper (Hessle) 
clay is also invariably of a bright yellow colour; but the lower is 
always blue, with a tendency in places to a steel-grey. This contrast 
is probably due to the fact that as the Hessle clay is the water 
bearing stratum at this point, that therefore the change in colour has 
been induced by the more active oxidation set up by the water. 
The enormous quantities of rock fragments that occur in both is 
a prominent feature of the beds, but as a rule the chalk fragments 
are more numerous and in a better state of preservation in the lower 
than in the upper. Derivative fossils are both abundant and various. 
Ammonites, Gryphea, Belemnites, Pectens, Galerites, and ferruginous 
and phosphatic nodules, all more or less rolled and broken, are 
among those most frequently found. The chalk fossils do not 
appear to be so plentiful, a fact that is probably due to their more 
decomposable nature, though echinoderms, worn beyond recognition, 
are occasionally met with. The arenaceous peaty soil which occurs 
in the upper portion of each of the pits is of a dull, jet black colour. 
It is massive and homogeneous when first cut, but it weathers on 
with the occurrence of mosses, diatoms, and the shelly marls with 
their freshwater molluscs would seem to indicate the former 
existence in this locality of a number of small meres. Some idea 
eastward of the golf-links when the scour of the tide has laid bare 
a considerable area. 
Present averages about 30 feet, and since the total thickness of the 
ulder clays in the district, as shown by the borings that were 
when the pier was being built, is 90 feet, and of this 40 
 Tepresents the height of the Cleethorpes ‘cliff’ above OD, it there- 
fore follows that the excavations will have to be carried down another 
20 feet further before the surface of the upper cretaceous beds 
Sept. 
“oe 
. 
