﻿Vol. 6 1.] ORDER OP SUCCESSION OF THE MANX SLATES. 365 



map. It may be noted, however, that the successive ranges diminish 

 towards the north in the northern part, and also to the west, the last 

 two having little of the high dip of the first two : namely, that from 

 Ballameanagh northward ranging from 60° to 20°, while the height 

 at the end is not much above 500 feet ; and that at Gob-y-Deigan 

 being nearly horizontal, and on the sea-shore. This seems quite 

 as easy of explanation by a series of subparallel faults radiating 

 from the south of the island, as by infolds of the strata to which 

 their regular north-westerly dip in a graduated amount does not 

 correspond. 



The distribution of the Schistose Breccia is dependent on the 

 range of the Barrule Slate, with the western side of which it is 

 always closely connected, and of which, except for the fragments 

 it contains, it would appear to be a mere accident. Many, indeed, 

 are the localities, especially in the north, which are included under 

 ' crush- conglomerate ' in the Geological Survey -map, in which there 

 is no sign of a fragment. The presence of this sign, however, 

 usually indicates that the rock is harder and ' shorter ' in the 

 grain. In the large range of Barrule Slate, which extends from 

 the west side of Snaefell to Eamsey, the fragment-bearing breccia 

 is found at its highest point in the island, 1100 feet, on the water- 

 shed of the Glen-Auldyn river. It is here very remarkable in 

 its contents. I call it the Hill-Series. Thence we pass by 

 the road south of Parkneakin, through the three localities on the 

 west side of Glen Auldyn,.on to Elfin Glen at the top of the quarry, 

 and finally to the Albert-Tower Crags, the mountain-road, and the 

 lower road to the Reservoir, all more or less in the direction of the 

 strike. The dip, though variable, might take it to the low ground 

 near the Hamsey road, and we find it north of Skyhill at the base 

 of the road slanting up the hill. 



The next series of exposures of the Schistose Breccia is connected 

 with the great mass of Barrule Slate, which rises to 1257 feet in 

 Slieaumonagh, but is lost sight of at either end. At one end is 

 the magnificent river-section under the farm of Druidale, terminated 

 by a fault crossing the river, and at the other, the equally, but 

 differently, magnificent crag, before described. The rest of the 

 section, from Tholt-e-will to Narradale and Cronk Sumark, is so 

 interfered with by faults and other displacements, that it is of no 

 use for teaching, but only for testing progress. 



In the third range of the Barrule Slate, which occupies the hills 

 to the north-east of Peel, we find the Schistose Breccia, where we 

 expect now to find it, on the west, running parallel to its boundary, 

 the intervening space being marked as Drift-covered ; while, in the 

 last locality where the slate occupies the shore, we find the breccia 

 faulted down at the south-western boundary at Gob-y-Deigan caves, 

 and mounting (fide Geological Survey-Memoir) at the other end 

 upon the slate. 



We thus find that the members of the series of the Manx Slates 

 are repeated again and again in the order as they are first deter- 

 mined, according as they are raised above the surface of the earth. 



