434 LAMPirOH: CLIFF-SECTION AT HILDERTHORPE. 
ceedings for 1882, which includes a drawing to scale and a description 
of the cliff-section for 910 yards, commencing at the harbour, and 
working southwards. If the folding-plate of that paper be referred 
to, the section shown in this photograph will be found about an inch 
to the left of the large reference letter C. 
There is a few feet of boulder-clay — the " upper purple boulder- 
clay " — at the foot of the cliff, but this being covered with talus, 
especially on the left side of the photograph, is not well shown. 
Patches of talus also obscure the bedding of the sands here and there 
throughout. 
Above the boulder-cla}' there is a rough irregular glacial gi'avel 
(not visible in the photograph) which is often curiously contorted and 
intermingled with the clay. 
The rest of the section is composed of the finely-laminated 
" warps " and sands with a little small gravel, which stand out so well 
in the picture. It will be noticed how these beds curve over the 
boss of boulder-clay on the right-hand side of the picture, and in this 
way they often fill up irregularities in the surface of the lower beds. 
In some places they are beautifully ripple marked, but this, though 
it may be traced here and there, is not so well shown in this part of 
the section as elsewhere. Near the top of the cliff, especially on the 
left side, it will be seen that the beds are puckered and twisted as if 
by contortions. This disturbance is very peculiar, and Mr. Dakyns 
has suggested (sujrra nit) that it may in some cases be due to incipient 
concretionary action. 
Careful search has failed to reveal any shells or other fossils in 
these beds, but on some of the laminae tliere are curious pittings and 
markings that look somewhat as though they may have been made 
by living creatures. 
For the whole of this laminated series I have suggested the 
name of the " Hilderthorpe Sands," and it is my opinion that these 
beds are of fresh water origin, and have been deposited in a shallow 
lake or estuary by the waters of a river coming down from the main 
wold valley, at a period closely following upon the retreat of the 
ice-sheet which spread out the boulder-clays. 
