401 walton : some new sections in the hessle gravels. 
The Boulder ('lav. 
The layer of boulder clay covers over both the gravels and the 
Chalk, so that there is no indication on the surface of what is found 
below. Over the Chalk it is only a few inches thick, but its thickness 
increases towards the east, so that at the east end of the large pit it 
shows four or five feet. Still further eastward, towards the lower 
ground, I am told that in draining, etc , it has been found to be from 
ten to twenty feet. On the south slope towards the Humber it also 
thickens out considerably, being at least from eight to ten feet. The 
base of the boulder clay at its junction with the contorted gravel, 
as seen in the section, is well defined, and is a slightly wavey but 
almost straight line. Where the boulder clay has been removed by 
the workmen, previous to digging out the gravel, the upper surface 
of the contorted layer is very rough and uneven, this uneven 
appearance being probably due to some extent, but not altogether, to 
the irregular solution of the underlying gravel by percolating water. 
The boulder clay is a somewhat sandy clay, reddish brown in colour ; 
it is weathered and shows no well-defined jointing. The lower 
portion is more sandy than the upper part. Xo trace of any shell- 
fragments has been found, and there are no lenticular patches of 
gravel or sand in the clay itself. 
The Boulder-. 
The stones contained in the clay are not very numerous, their 
average size being below four or five inches in diameter ; but a few 
larger ones of about twelve or fifteen inches have been found. 
On the eastern side of the excavations there are some local flints 
and small fragments of chalk all angular. The proportion of chalk 
and flint increases very rapidly towards the west, until where the 
clay overlaps the Chalk it is quite full of them, the distance being 
only two hundred to three hundred feet. The other stones in the 
clay are all well-rounded and icaterworn, especially the smaller ones. 
They lie irregularly in the clay ; one or two at the east end of the 
section were lying with their long axes from E. to S.E. and W. to 
N.W. and with the highest ends towards the S.E. They are not 
much scratched or grooved, only one or two so marked have been 
seen, and those had all been moved from their original position in 
