CONCLUSIONS ON PARTIAL EVIDENCE. 129 
anchorage even of the largest vessels. On the 
other hand, the Avon offers a decided case of con- 
tracted dimensions by the accumulation principally 
of sand-banks, which are here of large size. ‘T’o all 
appearance, this river in former years was of con- 
siderable breadth, but owing to general oceanic 
retreat, deposit of mud, and the occurrence of a 
partial ridge of rock at his mouth, it has now given 
place to a broad expanse of sand overspread with 
maritime vegetation. On the short but very high 
bar of rock which stretches into it, there is a large 
and in some spots very deep deposit of fine sand, 
accumulated either at the period of the general ele- 
vation of the sea before spoken of, or during some 
violent storm and tidal elevation ; once only in the 
memory of man has it been covered, viz. in the great 
storm of November, 1824, when also, the sea had 
free access to Slapton Ley. 
The observer of such matters affecting the ques- 
tion of oceanic usurpation and retreat need to be 
particularly careful to frame his conclusions upon 
the aggregate of collected evidence, since it not un- 
commonly occurs, that partial evidence indicates 
opposite results to that which might accrue from a 
consideration of conjoint facts. In the promotion 
of a general result Nature may effect circumstances 
which if separately considered would point to a 
conclusion exactly opposite to that which is going 
forward on the larger scale, thus, the successful 
attacks made by the ocean on the coast in exposed 
positions furnishes no argument against general 
oceanic retrocession and the filling up of estuaries 
&c. by alluvium, and so likewise, the information 
which thetraveller obtains at the mouth of the Avon 
of the encroachments which the sea is now effectu- 
ating on the sand-banks, proves nothing against 
the general deduction that the sea is in the mass 
retiring and heaving up more and more of this very 
R 
