392 



THE BRITISH ISLES. 



that the Shannon, instead of flowing straight into Galway Bay, from which no 

 natural obstacle separates it, strikes across a mountain range formed of hard and 

 solid rocks, through which it had laboriously to cut itself a passage. It is quite 

 clear that the gorge of the Shannon is not a work of recent date ; it was scooped 

 out long before the great central plain had been denuded of the masses of softer 

 rocks which formerly covered it. Then this mountain range formed no obstacle, 

 for the river flowed at an elevation of many hundred feet above its present channel. 

 At that remote epoch it first began to scoop out the ravine through w'hich 

 it now takes its course, and the work of erosion kept pace with the denudation 

 which swept away the coal measures of the great central plain. In this gorge, cut 



Fig. 198. — The Falls of Doonass, at Castleconneil. 



through Silurian slates' and old red sandstone, the river has a rapid fall, and 

 before it reaches the maritime plain pours its immense volume over a ledge of 

 rocks. Castleconneil, with its lofty towers, fine mansions, and green lawns 

 descending to the waterside, commands this sublime spectacle of a foaming river 

 rushing onward through a congregation of huge rocks. The eye grows giddy 

 as it follows the hurrying eddies. But, at the foot of the fall, all is peace. The 

 deep and silent water, reflecting the trees that grow upon the banks, lies dormant ; 

 the current is hardly perceptible ; and the river resembles a lake shut in by ivy- 

 clad walls. 



Below Limerick the Shannon enters its broad and winding estuary — one of 



