15 



dually shallowing like them as it descends; the stem of a tree rooted at the base 

 ascends the face of the rock and enters the bottom of the groove, following it till, as the 

 depth increases , it is lost to sight ; at the summit it re-appears and spreads its branches 

 above the rock. At the NE. extremity of this portion of the face, the rock retires a 

 few feet, and then stretches again to the NE. , shewing a high quadrangular face with on- 

 ly a few channels. 



Facing this side, and at a distance of IS to 20 yards, a much larger and more regular 

 mass rises in the jungle. The face opposite (and I am particular in noting the directions 

 of the faces, because they appear always to coincide with structural planes of division or 

 imperfect cohesion) is about NE. by N. , that is , nearly the same as that of the rock 

 opposite. This face is nearly quadrangular, and, judging by the eye , somewhat above 80 

 feet in height. The upper portion exhibits a few furrows, some of considerable depth, but , 

 as the face slightly inclines inwards , these terminate near the top. The NW. and SE. 

 face (i. e. that facing the strait or SW.) is more imposing still. It is 110 feet in length 

 and about 40 in height. It is slightly inclined inwards, and is exfoliating. The upper part 

 alone shews two or three furrows , a few feet in length. It is surmounted by a thicket 

 of shrubs. The rock is a syenite , white felspar in general constituting the great bulk. In 

 some places portions of it have a light greenish hue. The hornblende is irregulary dispersed , 

 generally in a state of confused aggregation, and sometimes mixed with felspathic grains , 

 but frequently also in long drawn streaks and seams. At one place it was so much in 

 excess as to give the fractured surface of the rock a very peculiar variegated appearance , 

 blackish green, light green, and a light iron hue, being variously intermixed with a lesser 

 proportion of white and greyish. On the SE. side the rock slopes to the ground so that 

 I was enabled to climb to the summit and examine it. It is throughout more or less fur- 

 rowed , but the furrows are irregular in their sue, positions and directions, and do not 

 approach to the symmetrical or artificial appearance of those on the sides of some of the 

 rocks. About the middle of the rock, from the bottom of the siope op. the SE. to the 

 edge of the opposite or NW. side , there are some well marked divisional lines running 

 NW. by N. nearly, but there are others less marked at various angles with these. The 

 rough holes and gutters on this part generally follow the same direction, which is also that 

 of the general slope. Towards the NE. face the summit slopes iu that direction , and 

 the hollows take the same course. Some of these are prolonged in channels which descend 

 the vertical NE. face, which is of considerably less height than the SW. The examina» 

 tion of this rock satisfied me that the slope of the rock, and the direction of the structural 

 planes of imperfect cohesion, determine the direction of the channels , and, this being the 

 case, the conclusion seems inevitable, that rain has been the great agent of erosion. On the 

 SE. face, where there is a gradual slope to the ground, the hollows cover the whole sur- 

 face, but are irregular, because there the rain torrents descended with less impetus, and their 

 action was not greatly aided by the gravity of the masses on which it acted. At some 

 places it has worn depressions of considerable depth and breadth along a line of division, 

 but, owing probably to the occurrence of portions of rock of a different and less decomposable 

 arrangement or apportionment of ingredients, these a*re separated by solid walls or small 



