241 
NOTES ON THE GLACIAL PHENOMENA OF 
UPPER RIBBLESDALE, 
IN REFERENCE TO THE EXCURSION OF THE YORKSHIRE 
NATURALISTS’ UNION, MAY 1892. 
J. G. GOODCHILD, H.M. Geor. Survey, F.G.S., F.Z.S., M.B.0.U. 
NOTWITHSTANDING the rapid strides that have recently been made 
in connection with Glacialography, there are still many points upon 
which some students are by no means clear. It may therefore serve 
a useful purpose if these notes are prefaced by a few general observa- 
re 
borne in mind, that vahoaeie nearly all alacial strie, and most of the 
deposits of glacial origin, all over Britain, date from the climax of 
the Glacial Period, yet the period during which any given area of 
similar general relief had been previously occupied by ice, was longer 
in proportion to the height of its latitude. Putting the same state- 
ment into a different form, we may say that, although the vestiges of 
glacial action in Ribblesdale are contemporaneous on the one hand 
with those of Finchley, and, on the other with those of, say, Perthshire, 
north bank of the Thames commenced only just before the great 
ice-sheet attained its maximum, and terminated almost immediately 
aiterwards, while the ponded back-waters of the ames were 
depositing the brick-earths and gravels along with their re-sorted 
Mammalian remains (Proc. Geol. Assoc. Vol. ix, No. 3). 
Then, in regard to some questions of glacial physics, a word or 
two may not be out of place. On the late visit of the Y.N. Union 
to Ribblesdale, considerable attention was given to a fine example of 
aroche moutonnte in the Midland Railway cutting just south of 
Horton. This showed in the clearest manner possible that the ice- 
Sheet flowing southward against this obstacle must have moved 
simultaneously, at different levels in at least three different directions, 
two of them almost diametrically opposite to each other; so that 
while, a few feet above the obstacle, the march of the ice lay nearly 
due south, yet on one side of the rock the ice flowed to the east, on 
the other to the west, while in a third position its course for a short 
distance lay upwards. It is no uncommon phenomenon on either 
the small scale or the large; yet the lesson it teaches appears to have 
August 1892. Q 
