Fingal and East Coast, 39 



the South. Esk, and again upon the Malahide estate, 

 where the road crosses it, at a level but a trifle higher. 

 It crops out on both sides of the valley near the 

 mansion of Mr. Stieglitz of Killymoon, on the level of 

 the plain ; and about three miles higher up it shows out 

 in the channel, and on the banks of the Break-'o- 

 day River, near the residence of Mr. Legge. It is next 

 detected forming low eminences at the foot of a high 

 flat hill a few miles south of St. Patrick's Head, which 

 is locally known as Thompson's Big Hill, and the 

 Elephant Hill. Upon the south-west aspect of this hill 

 the limestone beds form striking vertical escarpments 40 

 or 50 feet in depth, and certainly not less than 250 feet 

 above the plain, which at that extremity cannot be less 

 than 850 feet above the sea. 



Vertical clay-slate is again disclosed in this neighbour- 

 hood, and over it a long series of clayey conglomerates 

 and sandstones, &c., terminating as before in the crinoidal 

 limestone. 



Whence and however the clay-slate formation, com- 

 prising all its long sequence of constituent beds of soft 

 argillaceous schists, compact clayey sandstones, and 

 greywacke, may have been derived, its materials must 

 have been deposited in layers horizontal, or nearly so. 

 They now range from vertical to about 70° or 75°. 



The upheaving agent affecting it appears to have been 

 granite ; for every where this eruptive rock is met with in 

 its vicinity more or less abundantly. It is associated 

 with it for several miles along the course of the South 

 Esk from Avoca upwards ; it is associated with it 

 along the course of the St. Paul's River ; and in the 

 interval I found massive schorly granite, supporting clay- 

 slate, at the base of the dome of St. Paul's, and to some 

 height up its side. There also I found limestone, with 

 the intervening fossiliferous clays, &c., — the whole, as 

 usual, capped with enormous masses of greenstone. 



