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They varied in colour from pink to light buff, speckled with the 
usual iron-mould little dots, and were of varying texture, some 
harder and more silicions than others. That these fragments 
had not been subjected to much rolling action by water or other- 
wise was evident from their edges being but very little rounded, 
or their angles much abraded. If you ask me how they came 
there, my answer is—in the same way that the angular and 
subangular “headings” came in all our quarries around, a 
question still to be solved; ice, water, or atmospheric action 
and wear and tear, by one of these agents alone or by all 
three combined. 
Did time permit, and were it within the scope of these notes, 
one might perhaps be inclined to dwell upon the second of these 
_ causes, and attribute the enormous amount of denudation that 
has taken place around (as evidenced by the thick and massive 
beds of Conglomerate that fringe these hills) to water action. 
Indeed mathematics have come to aid us much in our 
difficulty, and to Mr. G. H. Darwin, and especially to the 
Astronomer Royal for Ireland, Mr. Ball, who has supplemented 
and enlarged, perhaps somewhat too much, Mr. Darwin’s theory, 
we are indebted for great help in their account of the important 
part the tides have played in the history of our earth. And if, 
according to Professor Ball, in the far distant ages of the 
Carboniferous period the tides were some hundreds of feet higher 
than they are at present, and swept over our heads 
some 500 feet above where we now stand, and if this mighty 
ebb and flow took place twice in the 24 hours instead of once, 
we see indeed that our tides are but the “feeble surviving 
ripples of those mighty tides” with which the ocean once pulsated. 
We have too a faint idea of the enormous power of this tidal 
planing engine, and may be less surprised and better able to 
account for the removal of so vast a mass of hard rocks. 
I have yet more evidence to lay before you. On Friday last, 
in company with Messrs. G. Horner, McMurtrie, and Sandys, I 
