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In the north-east of Antrim in the Barony of Cary, the geologist 

 travelling from Cushendun to Bally castle will go over a flat- topped 

 platform of mica slate, of our oldest type 750 feet high, extending from 

 Knocklayd, on the west, to Tor Point on the east, about 6 miles. On 

 this mica slate platform rest three roundish districts of chalk, and trap 

 in Knocklayd, in Ballypatrick, and in Carnlea, near the east coast. 



Between these two, little in space, but great in time, there are 

 missing many whole formations, as they occur in succession in other 

 parts of the globe. If the mica slate itself be not Cambrian, the 

 Cambrian is absent, so is the Silurian, and the carboniferous, with most of 

 the secondary rocksj as I have already stated. 



Brown Devonian Grit. 



This rock occupies a small district extending along the shore be- 

 tween Cushendall and Cushendun. It is three miles long in this 

 direction, and reaches inland from the shore about a mile and a half in 

 the widest part, through the top of Cross Slieve Mountain. 



The age of Sandstones is very difficult to be determined, because in 

 general there are no fossils in them, and they occur in formations of 

 every age. 



This brown grit, between Cushendall and Cushendun, has been 

 called Old Red Sandstone by every one who wrote about it. Among 

 ihose were Mr. Bryce, Mr. Mac Adam Sir Richard Griffith, and others. 

 A brown hard grit, exactly similar in appearance, occurs between 

 Pomeroy, in the county of Tyrone, and Lisbellaw, in Fermanagh ; 

 also a rock exactly similar in lithological character, in the Cur- 

 lew Mountains in Roscommon and Mayo ; in Galway, in the vicinity 

 of Killery Harbour ; at Mourne ; at Kilbride, near Lough Mask ; and 

 in the Dingle peninsula in Kerry. In all these places it is conform- 

 able to, and associated with, bands of rock, teeming with Silurian fos- 

 sils ; and though no fossils have been found in it in this locality, nor, 

 indeed, in this purple grit, anywhere that I know of, it is, neverthe- 

 less, I am convinced, an undoubted transition grit. 



It has even been stated that the part of this rock, in a band a fur- 

 long wide along the shore, is New Red Sandstone, because it contains 

 rounded pebbles, which give it a conglomeratic character, and that the 

 bottom beds of the new red sandstone in Red Bay are composed of a 

 rough strong conglomerate ; but conglomerates are common to sand- 

 stones and grits of every age. Some of the most magnificent conglo- 

 merates in Ireland are at Lisbellaw and at Lisnarrick, in Fermanagh, 

 and at Blackwater Bridge, near Killery Harbour, in Galway, and these 

 are all in Silurian rocks. The lower beds of the Old Red Sandstone 

 exhibit a conglomerate everywhere it occurs. Conglomerates are no 

 proof of the age of a rock. Besides this, the conglomeratic character 

 near Cushendun is not confined to the coast. It is in the hills of Bal- 

 lybrack, a mile north-west of Cushendall, which seems to be all com- 

 posed of it. It is seen in the bye-roads about that hill plentifully. 

 Even in the stream at Cloghs are seen in the brown grit many pebbles 



