1886] North America, Great Britain and ireland. 923 
1 From Skipton northward the phenomena are more complicated. 
7 A tongue of ice surmounted the watershed near Skipton and 
È protruded down the valley of the Aire as far as Bingley, where 
its terminal moraine is thrown across the valley like a great dam, 
reminding one of similar moraine dams in several Pennsylvania 
valleys. A continuous moraine was traced around this Aire 
glacier. Another great glacier, much larger than this, descended 
Wensleydale and reached the plain of York. The most complex 
_ glacial movements in England occurred in the mountain region 
about the Nine Standards, where local glaciers met and were 
overpowered by the greater ice-sheet coming down from Cumber- 
nd. The ice-sheet itself was here divided, one portion going 
southward, the other, in company with local glaciers and laden 
with the well-known boulders of the “ Shap granite,” being forced 
eastward across Stainmoor forest into Durham and Yorkshire, 
l finally reaching the North sea at the mouth of the Tees. The 
: terminal moraine runs eastward through Kirby Ravensworth to- 
ward Whitby, keeping north of the Cleveland hills, and all East- 
ern England and south of Whitby appears to be non-glaciated. 
On the other hand all England north of Stainmoor forest and the 
fiver Tees, except the very highest points, was smothered in a 
=~  Saof solid ice. a 
. There is abundant evidence to prove that the ice-lobe filling 
Irish sea was thicker towards its axis than at its edges, 
and at the north than at its southern terminus, and that it. 
Was reinforced by smaller tributary ice-streams from both 
ok England and Ireland. It may be compared with the glacier of 
_ the Hudson River valley in New York, each having a maximum _ 
thickness of something more than 3000 feet. The erosive power. 
x of the ice-sheet was found to be extremely slight at its edge but 
_ More powerful farther north, where its action was continued for a 
nger Period. Towards its edge its function was to fill up ine- 
_ Walities rather than to level them down. It was held that most 
glacial lakes are due to an irregular dumping of drift rather than 
. coinciding With those in America to confirm this conclusion. 
MGs facts oa both aides of the Aiat indicate thar the 
. 
mits lower portion. It was also shown that a glacier in its 
ance had the power of raising stones from the bottom to the - 
any scooping action. Observations in England and Switzer- © 
~PP€r portion of the ice-sheet may move in a different direction 
