1823.] Mr, Moyle on Granite Veins. 92r 



15°. Within a few feet of these two, a third vein starts out at 

 nearly the same angle, and proceeds in the same direction. 

 These three veins are throughout nearly of the same thickness, 

 viz. each about five feet.'^ 



Whether the recent fall from the clifF during the last winter 

 has altered the features of the veins, or exposed a new one, I 

 cannot state with certainty ; but there is distinctly to be seen at 

 present four separate veins as represented in the section ; the 

 lowest is not more than three feet thick, until it arrives at the 

 point (c), when it suddenly widens to more than six feet, at 

 which thickness it continues on to the west. The vein imme- 

 diately above this {b) commences about five feet in thickness, 

 and continues on at the same width as far as immediately over 

 the widened part of the vein below, where it decreases to about 

 2-1 feet, and so continues on to the recess. These two are 

 at about an angle of 15°. The next vein (c) is about seven feet 

 thick throughout, and rises at about an angle of 30°, and it is in 

 this vein principally where the fragments of slate are so very 

 conspicuous ; some of these fragments measured from three to 

 four feet in length, and from four to six inches thick : they show 

 themselves in the veins in the manner represented in fig. 3. At 

 other places the slate may be seen apparently shooting into the 

 veins of granite in a tortuous manner, fig. 4 : a fourth vein {d), 

 about eight feet thick, is found rising at an angle of about 45° 

 till it is lost in the alluvial soil above. This vein does not appear 

 to be noticed by Mr. Sedgwick. 



On examining some of the rocks lately fallen, many fragments 

 of slate are to be found imbedded in the granite, and several 

 masses of slate may be seen with granite adhering to one or 

 more of its sides, and so firmly attached to it, that the granitic 

 vein itself has split in preference to separating from the slate. 



" The two lowest veins preserve their course without being 

 much deflectecl for some hundred feet, and from the place we 

 first remarked them, disappear behind a projecting part of the 

 cliff. On turning this projecting ledge, we suddenly reached a 

 recess, the lower part of which was filled with the ruins from 

 the higher of the overhanging rocks. The western side of this 

 recess is composed of killas, intersected by some small granitic 

 veins." About half of the western side only is composed of 

 killas ; close to the alluvial soil is granite 15 feet thick ; then 

 comes a thin layer of slate about three feet thick, which is 

 again followed by a granitic vein (g), about 15 feet in thickness. 

 The remaining part of the cliff below is all slate, which entirely 

 disappears about 200 feet further west than this recess. In this 

 last described slate are to be seen blocks of rounded granite, or 

 wh^t in other situations would be called bowlders of small 

 dimensions imbedded in the ceiitre of the slate as seen at (e). 

 This granite has a different aspect from any other in the imme- 

 diate neighbourhood, being of a darker and firmer texture, and 



