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its source. The drainage of the great depression enclosed by the 
Matterdale Fells, Helvellyn, Fairfield, and High Street gathers in 
Ulleswater, and eventually flows thence by way of Poola Bridge, 
where the outflowing stream received the name of the Eamon. In 
truth, however, the Eamon rises in the mountain tops around 
Patterdale, and Ulleswater is nothing more than a local expansion 
of the upper part of the Eamon, which has been somewhat widened, 
and deepened, by glacial action. The Ulleswater depression is, 
simply, the upper part of the Eamon valley. Below Poola Bridge 
the river cuts across the big escarpment of the Mountain Limestone, 
which extends across from Askham to Penruddock. If we could 
fill up the gap (or only a little of it) that the river has made in 
excavating its channel through this escarpment, the stream could 
easily find an outlet past Dacre, Hutton, and Troutbeck, and 
thence down either the valley of the Cawda to Carlisle, or down 
that of the Greta to Keswick and Cockermouth. The rocks along 
much of this line are more easily eroded than are those through 
which the river now frets its way. After traversing this limestone 
escarpment the river reaches another transverse depression. A 
dam a hundred feet in height thrown across the Eamon just above 
Skirsgill, would turn the whole of the water north-westward into 
the Petteril below Catterlen. Nevertheless, the Eamon has not 
taken advantage of this easier course open to it, but has continued 
its course, without any important deviation, right across a second 
escarpment, formed in this case by the Penrith Sandstone. Thence 
it flows into the Eden. The valley of the Eamon below Penrith 
is nearly three miles in width, and is nearly five hundred feet in 
depth. Clearly, these gorges represent the least-modified parts of 
the old river valley, and the depressions that traverse the river 
valley elsewhere represent such parts of the surface as have been 
lowered by subaerial denudation at nearly or quite the same rate 
as the river has lowered its own channel. When the Eamon began 
to flow, its course was at a higher level by more than two thousand 
feet than it is at present. As the general level of the surface has 
been lowered by prolonged atmospheric waste, the river has main- 
tained its present course, without being in any way influenced by 
