_ 820 ON THE GEOLOGY OF THE ISLAND OF AQUIDNECK. 
It will be noticed that the island has no streams of consider- 
able size ; none, in fact, which could have been competent to create 
the wide and deep depressions we find in the larger valleys of the 
island by direct abrasion. In some of the minor valleys near the 
shores, as at the glen on the east side of the island, we have real — 
stream valleys with the normal V-like excavations, but in the — 
larger depressions occupied by the streams the form is very much 
more rounded and the size usually many times as great, giving 
broad U-shaped troughs, in which the streams, though in fully 
close contact with the bed rock, have very little effect upon it 
They are manifestly incapable of creating the valleys in which 
they flow. To account for these depressions we are forced to 
suppose either of several things; we may suppose that the valleys 
are the relics of the topography which may have existed here before : 
the Bay was formed, and that the streams which made them gath- : 
ered their volume in the land which then occupied the space where : 
the waters now lie and a part of the region beyond; we may seek 
an explanation of their formation in the action of the sea during 
a former period of partial submergence, a probable source of 
valley-making, according to the view of many geologists, or e 
may perchance find that to the erosion of the ancient si 
streams we owe the development of what the brooks only began. 
The first supposition is manifestly inapplicable toa number 
that which owing to the want of any well established 
been termed the north valley. being that occupied by thes : 
which debouches just south of the Aquidneck coal mines, an 
extend across the island but has its head within fifty feet of 
highest hill. On the part of the island to the south of this ` 
we have several considerable depressions of the ean 
Only one of these, that which lies immediately to the: 
Newport, is continued clear across the island, but Oe 
central part of the valley lies so high as to afford hardly s 
able impression of its having been the valley of an anei 
A careful consideration of the question has led me to 
that this hypothesis is inapplicable to any of the valie 
island. The question of the marine origin of these mE 
easily dismissed. If competent to produce these valleys We 
find the sea still at work extending their contours a 
contact of sea and land. It is sufficiently evident n 
action is now going on. The sea is now making slight ; 
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