154 
Mr Young on the Formation of 
In like manner, the Biver Tees, and its tributary streams, 
cannot be conceived to have given the fronts of the Cleveland 
Hills their shape, and formed the deep recesses between them. 
The Leven, which collects a great part of the streams that flow 
from them, makes its way through deep beds of alluvium, which 
it cannot have deposited ; but though it has deepened its chan- 
nel, by wearing away the soft alluvial beds, it has made little 
impression oh the sandstone strata, in the few places where it 
reaches them. To ascribe to currents so limited in their opera- 
tions, effects of such magnitude as the shaping of mountains, 
and the formation of extensive valleys or plains, is altogether un- 
philosophical. 
Besides, what shall we say of those valleys in which there 
are no streams, of which we have so many in our oolite hills 
and chalk hills ? And what shall we say of the subterraneous 
channels of the becks that flow into the vale of Pickering? 
Have these channels also been excavated by the streams ? Or 
how shall we account for another singular fact, that the 
becks or rivulets which flow southward from the highest range 
of the alum hills, on arriving at the oolite hills, pass directly 
through them, instead of turning into the valley that runs along 
their northern fronts ? Had a river run in that valley, all these 
becks would have fallen into it, and pursued their course with 
it to the ocean, without breaking through the oolite hills at all ; 
or, at the most, one passage through these hills, would have 
served for the whole. When, therefore, we see each of these 
becks holding a straight course through an opening in the oolite 
hills, exactly opposite its channel in the alum hills, there is no 
way of explaining the phenomenon, but by supposing that both 
parts of its channel have been formed by the same break in the 
strata. 
Another proof that river courses have been produced by 
such breaks and denudations, we find, in those places where the 
heads of two opposite valleys run into one, their heads forming 
a low marsh, from whence the waters flow in contrary directions. 
Thus, Newton Dale is connected with the Vale of Godeland by 
a narrow marshy vale or hollow, above a mile long, called the 
Fen. This fen, in which the waters are stagnant, has the same 
kind of high banks as the dales which it unites, and of which it 
