Stratigraphical Geology. 79 



Newtownards. Here the beds are frequently ripple-marked, 

 or show suncracks, and occasionally rain pitting, with the 

 lucidity of a text-book diagram. Frequent layers of clay 

 separate the massive beds of sandstone. False bedding is 

 to be frecjuently observed, particularly in the sides of the 

 rock faces of the passage leading into the main quarry to 

 the south of the hill. The rock is extensively quarried for 

 building stone, and, if carefully selected, yields an excellent 

 building material for local use, for which there has always 

 been a large demand. 



The preservation of the Triassic strata at Scrabo is due 

 to the protection afforded by the capping of Tertiary basalt. 

 The various sections show, in a remarkably distinct manner, 

 dykes and sills of the intrusive basalt. In the north quarry 

 the sills can be seen branching from the vertical dyke ; 

 they can be traced and followed for considerable distances, 

 sometimes following the bedding planes of the sandstone, 

 and at times breaking through them for short distances 

 to renew their horizontal course again for a time. In the 

 south quarry a dyke about seven feet wide can be seen 

 breaking through two such sills, and ultimately through the 

 basalt capping overlying the sandstone. For the student 

 of physical geology there are few places that can excel 

 Scrabo Hill in furnishing, in a limited space, so many 

 illustrations in situ of the principles of his science. 



Keuper Clays occur at various localities near the flank 

 of the escarpment along the shores of Belfast Lough, 

 and at an elevation of 150 feet near Woodvale Park, on 

 the western side of the city of Belfast. The beds consist 

 of thick red marls with bands of grey marls and thin 

 sandstones. In places the marls attain a thickness of 800 

 feet. Numerous bands of gypsum occur irregularly through 

 the mass ; some of these bands, as found on the Forth 

 river, being six inches in depth. These bands are well 

 exposed on the railway cuttings beyond Kilroot and 

 Cloghan Point, and also occur on the shore at Waterloo, 

 north of Larne Harbour, where the marls and sandstones 

 merge into the Rhastic series. 



Rock Salt occurs in considerable abundance in the 

 Keuper marls at Carrickfergus and Magheramorne, and 



