THE PICTOU COAL FIELD — POOLE. 249 



is the summit south of D. McLean's house that overlooks all the 

 country to the eastward, while the depressions among the hills 

 to the southward are looked down on from the elevation near 

 the Mountain church. Then at Mountville from the top of a 

 neck of trap a view of the valley of McLellan's brook and the 

 East I'iver is commanded. 



A dark hornblendic rock, partlj^ vesicular, full of fine crystals 

 of felspar, hereinafter spoken of as ' trap,' supplied many 

 boulders to the Lower Carboniferous conglomerate that rests 

 on the Silurian slates at the grist mill on McLellan's brook ; and 

 on the flank of Weaver's mountain a similar material forms a 

 paste for what appears to be a tufaceous conglomerate of greatei' 

 age. 



McLellan's brook on entering the ravine that separates 

 Weaver's and McLellan's mountains cuts through a low isolated 

 knoll of crystalline rock associated with Cambro-Silurian strata, 

 and through the same series eastward of this point project many 

 masses of diorite. Those ly the side of the east branch of 

 McLellan's brook, which for convenience may be called Stewart's 

 brook, furnished material for the brecciated conglomerates 

 that rest on them. 



At the base of the western escarpment of Weaver's mountain 

 the surface is covered with debris of altered rocks identical with 

 the most highly metamoi-phosed beds cut through b}' the East 

 river at Fish-pools, which makes it probable that the intervening 

 unexposed ground is likewise occupied by a continuous series of 

 these beds traversed by d3^kes similar to that seen at Chisholra's 

 culvert on the west bank of the East river, elsewhere men- 

 tioned. This dj^ke could not of course have produced the indur- 

 ation that there extends over so wide an area, but doubtless it 

 was contemporary. 



On the north side of the field the range of high land records a 

 dine of volcanic activity which probably extended to the west- 

 ward, though now overlaid by the New Glasgow conglomerate of 

 'Green hill. Waters' l)rcok Mr. Fletcher found to cut through 

 trap at Powers' quarry and green felsites are exposed at the 

 Intercolonial railway bridge over McCulloch's brook. 



