272 
DAVIS : ERRATIC BOULDERS. 
down Lune Dale and towards the Irish sea ; on the one side How- 
gill Fells, and on the other — descending 1 the valley in which was 
the river Rawthey— between the Howgill Fells and Baugh Fell. 
Another branch of this great sheet of ice ascended Mallerstang 
and passed over the watershed of the Eden at Lunds, descended 
into Garsdale, and crossing the eastern spur of Rysel descended 
into Dentdale ; thence the course of the moving mass of ice appears 
to have been westwards of Whernside, over Bleamoor and along 
the limestone plateaux of the Ingleton Fells. A few miles south- 
wards the glacier was divided by the slopes of Ingleborough ; the 
westerly division passing down Dale beck, and the eastern passing 
for the major part into Ribblesdale ; being deflected to a more 
easterly direction by the great spur from Ingleborough, Simon's 
Fell. Scratches along the route are not uncommon, and have been 
found on the slopes and summits of the mountains to a height of 
more than 2000 feet. On Simon's Fell scratches have been seen 
by Mr. Tiddeman at a height of 1225 and 1350 feet. These have 
a general north and south direction, curving in a direction parallel 
with the form of the mountain. It is evident that the scratches 
were not made by glaciers descending Ingleborough, or they would 
have indicated that the ice was travelling in an easterly direction. 
If it be accepted that the glacier was pursuing a southerly 
course as indicated above, then the glacier must have extended 
across the Ribble Valley to the foot, and a long way up the sides 
of Penyghent ; this gives a breadth of 7 or 8 miles with a thick- 
ness of 750 feet. Several scratched rocks occur on the eastern 
side of the Ribble valley up to a height of 1300 or 1400 feet — about 
the same height as on Ingleborough. 
As the glacier or ice-sheet descended southwards it is probable 
that it would be divided into two parts by Monghton Fell, (1402 
feet) ; the easterly one passing down Ribblesdale ; whilst the 
westerly one passed into Crummack valley and over the limestone 
plateau of Norber — about 900 to 1100 feet above the sea level — 
and thence into the broad galley of the Wenning and its tributaries. 
It was during the passage of the ice down Crummack valley that 
