36 NOTES ON THE GEOLOGY OF MAKIA ISLAND, 



embedded ice-borne detritus. Above there is a magnificent 

 cliff of conglomerate about 40 feet high consisting of 

 pebbles and boulders set in a matrix of calcareous and 

 felspathic sandstone, which h^s decomposed by the action of 

 percolating water and formed numerous stalactitic growths 

 descending from the overhanging projections. The pebbles 

 are mostly quartzose, ranging in size from the tiniest par- 

 ticles up to large boulders, interspersed with boulders of 

 granite and pieces of slate, schist, and quartzite of the 

 older formations. It is resting in a kind of pocket scooped 

 out in the granite, and is no doubt contemporaneous and 

 homogeneous with the conglomerates^ across the bay. A 

 dyke of diabase comes right thi'ough the middle and a sill 

 of the same material is resting on the top. The granite of 

 Boat Harbour is a very coarse-grained tourmaline granite of 

 handsome appearance. The felspar crystals which pre- 

 dominate are often two to three inches long, and the 

 crystals of the other constituents are correspondingly 

 large. Tliis granite should make a valuable commercial 

 product quite equal to any of the imported article. It is 

 very striking in appearance and should take a splendid 

 polish. It is by far the finest granite I have seen on the 

 East Coast. It extends round Cape dee Tombeaux and 

 passes under the Pei'mo-Carboniferous basal beds which 

 appear in the next little bight, and which are themselves 

 capped bv Cretaceous diabase which forms an overlying 

 spur from jVlt. Maria. Between the next point and Cape 

 Mistaken, usually known as Ragged Head, the granite has 

 suffered a certain amount of deformation, but whether dur- 

 ing consolidation or subsequently is hard to determine. 

 The jointing is most irregular and in places highly con- 

 torted. Around Cape Mistaken, a bold granite headland, 

 we come in sight of a magnificent panorama. The great 

 moamtain-mass of the Bishop and the Clerk here ap- 

 proaches the sea, and slopes precipitously from its summit 

 down to the water's edge. It consists of Permo-Carbonifer- 

 ous limestones and marine mudstones, resting on a bed of 

 granite, and capped by Cretaceous diabase exhibiting 

 columnar structure in the cliffs along its summit, forming 

 the cockscomb-like Bishop and Clerk. 



Right under the eastern end of the latter mountain 

 the granite gives way to a series of rocks which Dr. 

 Clarke informs me are quartzites. These will probably 

 then be of the same horizon as those of Riedle Bay. They 

 have been highly contorted by the intruding granite; 

 anticlines and synclines are frequent and the plications 

 are most intricate. Where not folded the strata are all 

 standing on edge. Great blocks are also to be seen em- 



