252 CROFTS : NOTES ON ALEXANDRA DOCK EXTENSION, HULL. 
that from the shape of its preglacial mouth its course past Hessle 
is not extremely ancient. Off the Ferribys there is a cHff of 
boulder clay which appears to be the remains of a moraine which 
no doubt at one time dammed the Humber waters back,"^ 
a considerable task at the present time, but granted a high water 
level of only 30 ft. lower than at present, the sections now 
exhibited suggest a bank more than equal to such a task. 
The perfect preservation of the cherries found in the marl 
overlying the peat bed seems to suggest that a flood occurred 
when the cherries were ripening on the trees. The level surface 
of the marl with the shells from the bed above penetrating into 
small crevices may suggest that the surface was dried before 
the subsequent final inundation, which took place, so far as can 
be read by the method of deposition of the warp, through 
a gradual subsidence. 
With regard to the pieces of charcoal, an occurrence which 
had a parallel in the Albert Docks on the west of the city 
(in fact the two sections strongly resemble one another!), no 
traces of human agency were exhibited, and Dr. Jessen, of the 
Danish Geological Survey, informs me that charcoal is of 
common occurrence in the peat beds of Denmark, and due to 
natural ignition. 
The Xorth Eastern and Hull and Barnsley Railways con- 
template the construction of a large dock to the east of the 
works described in this paper, and it is to be hoped that the 
sections will, in connection with the Albert Dock and these 
w^orks, assist to complete the record of the strata under the city 
of Hull. 
I have to thank Mr. R. Pawley, C.E., the engineer to the 
Hull and Barnsley Railway and Dock Co., and Mr. J. W. 
StaJbher, F.G.S., for assistance in getting these notes together, and 
Mr. W. S. Parrish, for assistance with the photographs. 
* Notes on the Drifts of the Humber Gap. J. W. Stather, F.G.S. 
Proc. Yorks. Geol. and Polytec. See., Vol. xiii., Part II. 1896. 
t Albert Dock, Hull. J. C. Hawkshaw, F.G.S., Q.J.G.S., Vol. xvii. 
1871. 
