OS 3tr, Mbyle on Granite Veins, " [Aug. 



" For ft considerable extent beyond this point, the whole base 

 of the clift's is covered with vast fragments of the veins which 

 have been denuded by the surrounded killas becoming decom- 

 posed ; one of these is 10 feet thick. In general they are of a 

 brilliant white colour, and of a fine granular texture, sometimes 

 containing witliin themselves parallel veins composed of large 

 crystals of quartz and felspar, and proved to be of contempora- 

 neous origin by the long spiculoe of schorl which pass without 

 interruption, through both the quartz and felspar." 



These coarse granitic veins within the granite are best seen 

 in many of the huge blocks on the beach ; one block in parti- 

 cular, I observed, that has one of its sides nine feet long, and 

 seven broad, covered with these immense crystals of quartz and 

 felspar, and which most probably had separated from its fellow, 

 by the fall from the clin. One crystal of felspar I separated 

 which measured 4i inches in diameter These coarse veins, 

 generally speaking, are not more than from four to eight inches 

 thick ; but much of the granite apparently/ forming the matrix of 

 the beach, in this place, seem to be wholly composed of these 

 large crystals, in which is found some schorl, and scarcely any 

 mica ; while other parts of the granite have merely the large 

 felspar crystals imbedded in it, as to render it completely porphy- 

 ritic. One block of considerable magnitude has a vein of deep 

 coloured amethyst passing through it, several small crystals of 

 which I collected. 



" Beyond the ruin of these veins, there is a bed of granite one 

 foot thick, and about 40 feet in length and breadth." This is 

 the coarse-grained granite just alluded to, but it varies in thick- 

 ness from one to five feet. This " passes under the cliff, and 

 to all appearance alternating with the slate, but which, as in the 

 former instance, turns out to be a granitic vein. Advancing 

 further to the west, the rocks are beautifully intersected with 

 veins of the like nature, the lower part being cut through by a 

 well defined vein of about a foot thick, while the higher parts 

 are traversed by innumerable ramifications ; the lower branch 

 after keeping the direction of the slate beds, for a dist- 

 ance of 60 feet, suddenly rises in a perpendicular direction to 

 the top of the chff. The whole of this system of veins after- 

 wards unite in one trunk, which after traversing a projecting 

 ledge of rocks, descends in an oblique direction into a great 

 mass of granite, which form a part of a natural cavern. ^lear 

 this spot appears a very large mass of granite, which seem 

 to be the root of the gigantic veins, which proceed from 

 this point, and rise in broad white lines towards that part of the 

 cliff which reposes immediately on the central granite. Splinters 

 of clay slate are here seen imbedded in the middle of the granitic 

 veins. 



" From this point two large veins separated by a lancet- 

 shaped mass of slate, rise towards the west at an angle of about 



