516 MR. P. F, KENDALL ON A SYSTEM OF [Aug. 1902, 
been a depth of about 150 feet of water over the pass; but as the 
Moss-Swang overflow was deepened, the Kildale pass became awash, 
and at the lowest level the overflowing stream would actively cut its 
way across. ‘The evidence of this stageis very clear. Any overflow 
through the pass in either direction would, of course, be checked by 
the tranquil waters of a lake, and such coarse detritus as it carried 
would be cast down in the form of a delta. Now, at Commondale, 
where the narrow valley of Sleddale Beck expands, there is a great 
mass of gravel extending up the southern slopes to about the 
600-foot contour, and forming a very well-defined plateau at 550: 
to 575 feet O.D. It bas a very steep face looking eastward, due 
perhaps to the winding of the beck against it. The gravel consists 
mainly of Jurassic sandstone, but there are also many foreign stones, 
the most significant of which is a small boulder of Shap Granite. 
I infer that this material constitutes the delta of an overflow down 
Sleddale Beck, which was arrested by standing water at levels from 
600 feet down to about 560 feet. 
The gravel extends down Kskdale for about 2 miles, as an 
infilling of the floor in which the river has cut a new valley. At 
Holme Bank it forms a barrier across the valley, and the river has 
cut through the live rock on the north side. Here the top of the 
gravel-mass is flattened off at an altitude of between 525 and 
550 feet, which I think represents a stage of Lake Eskdale when 
the withdrawal of the ice-barrier at Moss Swang opened a free way 
to the Fen-Bog overflow, the level of which is about 525 feet, a 
sufficiently close correspondence to be worthy of observation. 
This second plateau is very distinctly lower than the one at 
Commondale, and I regard it as evidence of a partial redistribution 
ot the materials of the upper delta when the lowering of the lake 
caused an extension of the stream across its delta. <A third stage is 
represented by a gravel-flat extending to the eastward of the Howe 
at Danby, at an altitude just above 500 feet. This, however, belongs 
to a phase of the later history of Lake Kskdale which cannot be 
described at this stage. 
I may now say a few words about the post-Glacial history of the 
West-Bank drainage. 
Whether Sleddale Beck was ever captured by the Leven drainage 
or not I am unable with any confidence to affirm ; but if, as I have 
surmised, it had been, then the great flow of water which took place 
eastward to Lake Eskdale must have had the effect of cutting back 
the watershed and recapturing it. This shifting of the watershed 
would gradually begin to operate upon the channel between Sleddale 
and the Leven across West Bank. Ifthe erosion were arrested at 
this stage, we should find that the Leven would remain a constituent 
of the western drainage; but if, on the other hand, the erosion 
proceeded farther, we might have the Leven in its turn recaptured. 
This view I held at one time, but subsequent investigations have 
somewhat weakened my confidence, and I am content to state the 
facts and the alternatives, and draw no deductions. 
