VALLEYS EXCAVATED IN THE NORTH AND EAST OF IRELAND. 207 
EVIDENCE OF DILUVIAL ACTION IN IRELAND. 
With respect to Ireland, I shall adduce a few facts only, to show 
that it presents diluvial phenomena altogether identical with those 
in England and Scotland. 
In the Philosophical Transactions for 1808, Dr. Richardson has 
pointed out the effect of mighty currents of water in excavating 
valleys, many hundred feet deep, in the county of Antrim, and 
adjoining parts of the north of Ireland; and Mr. Weaver, in his 
very valuable Memoir on the Geology of the East of Ireland, in the 
fifth volume of the Geological Transactions, p. 294, has discussed 
with his usual accuracy the subject of the excavation of valleys, and 
the gravel produced by denudation in the counties of Wicklow and 
Wexford. 
“ It seems impossible,” says he, “ to consider the form of any con¬ 
siderable portion of the surface of the earth, or to reflect even upon 
the nature and disposition of its alluvial tracts, without recognizing 
the powerful agency of an agitated fluid in a state of retrocession. 
The abrupt and curved outlines, the fractured surfaces and de¬ 
nudations of extensive tracts, the sinuosities of glens, defiles, and 
valleys, the salient and re-entering angles, the plains, all betray its 
course and moulding force. To ascribe such appearances to a 
gradual degradation produced by the influence of the atmosphere 
and the current of streams, seems to be assuming causes wholly 
