FORMATION OF VALLIES. 97 
If these should bethought ambiguous examples of the action 
of currents, there are others where the fragments can be traced 
back, along the track of the current, to the rock from which they 
were torn. Instances of this kind occur in England, which prove 
that in that country, the movement of the waters was from the 
northwest towards the southeast. In many parts of the northern 
States, vast heaps of sand, gravel, and rounded pebbles, are piled up 
in the heart of primitive districts which must have been brought 
thither by currents. They are sometimes many feet in height, 
and cover extensive tracts. When cut through by torrents, they 
exhibit layers of rounded stones and sand, of different degrees of 
fineness, resting on each other, and different from the subjacent 
rock on which they repose. If we except the low country ; parts 
of which I have sometimes suspected to have an intimate con- 
nexion so far as relates to the time and mode of their formation 
with these deposits; we have no similar appearances in North 
Carolina. 
Many valleys have been formed by the action of currents. 
" When a valley takes its beginning, and continues its whole ex- 
" tent, within the area of strata that are horizontal, or nearly so, 
" and which bear no marks of having been moved from their ori- 
" ginal place, by elevation, depression, or disturbance of any 
" kind ; and when it is also inclosed by hills that afford an ex- 
" act correspondence of opposite parts ; its origin must be refer- 
" red to the removal of the subtances that once filled it. And as 
tl it is quite impossible that this removal could have been pro- 
"duced in any conceivable duration of years, by the rivers 
"that now flow through them, we must attribute it to some cause 
{i more powerful than any at present in action, and the only ad- 
"missible explanation that suggests itself is, that they were exca- 
" vated oy the force of water in motion." — Buckland, Reliquiae, 
Diluvianse. 
Hutton and Playfair maintained that all vallies have been form- 
ed by the long continued erosion of the streams which actually 
run through them ; but there are innumerable instances where 
streams do not exist, or where they are wholly inadequate to the 
production of the condition of things that is observed. From the 
effects of the water that falls under the form of snow, or rain, 
upon the soil of our fields, in forming gullies, and sweeping away 
the finer particles and depositing them in the beds of the rivers ; 
the idea that the vallies in which those rivers flowhave been scoop- 
ed out in a long succession of ages, strikesthe mind in the first in- 
stance, as in a high degree probable. But when we attend to the 
actual progress of the water in wearing away their beds, and ob- 
serve also the sharp angles of the rocks to a great height on each 
side, and the absence of those marks of attrition which must have 
been found, had the valley been created in this way, we see the 
necessity of a more efficient cause. If we trace the streams to the 
ocean also, we find the deposits at their mouths by no means 
9* 
