﻿364 



THE REV. J. F. BLAKE ON THE 



[May 1905, 



Map aDd Memoir serving as guides), from Gob-y-Deigan on the 

 west, to Maughold Head on the east. 



Thus, the Agneash Grit, characterized in the field by being finely 

 quartzitic, laminated (often closely), having a north-westerly dip of 

 various degrees (often high), being succeeded by laminated slates, may 

 be followed over the high ground above Agneash to Trinity Church, 

 west of the Douglas road and south of Corrany ; and the Grit is 

 seen in nearly-vertical bosses in the cliffs, and on the overlying 

 surface at Maughold Head (see fig. 4, below). So far have I traced it 

 towards the north. It doubtless continues to the south as mapped, 

 and occurs again in the same relative position, with the slates of 

 South Barrule and Cronk-ny-Arrey Lhaa. But, from all the areas 

 to the north-west of the Barrule main axis, the above-described 



Eig. 4. — Agneash Grit, looking east, seen nearly vertical at 

 Traie Ear Jean. 



characters are absent, and the rocks mapped as ' Agneash or other 

 grits ' must belong to the latter category, and have no connection 

 with the Slate Series. 



_ The overlying strata, that is, the Snaefell Laminated Slates, in 

 like manner may be traced from the hills behind Agneash to 

 Maughold Head, where they cap the head itself ; and this headland, 

 though not high as compared with the axial range, is higher than, 

 and sharply protrudes from, the country immediately surrounding it, 

 which is made up of rocks of a different character. We may see 

 the Laminated Slates extruded at the sea-level to Port-e-Myllin, 

 close up to the (mapped) commencement of the Barrule Slates, 

 recognizing them by their dark colour, soft texture, and lamination 

 combined, as well as by the curious cross-cleavage, which looks 

 more like areas of contraction filled in with a lighter-coloured secre- 

 tion, crossing irregularly from hard band to hard band, without 

 moving them by anything like ' strain-slip.' 



Since the Barrule Slates have been taken as the standard of 

 comparison, there is no occasion to discuss their distribution, which 

 will not differ from that indicated on the 1-inch Geological Survey- 



