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14 



or slight fissures running in the direction of its length or NW. by W. and SE. by E. 

 nearly, a line which cuts the hill of Tanjong Pamoodang on the main. In the lower of 

 the two grooves or channels there is a cup, the surface of which is rusty coloured. Two 

 sharp pieces of rock project from it. One of them is of a very dark green owing to the 

 hornblende greatly predorainating. In the cup I also found a globular volcanic stone, semi- 

 vesicular on one side. It is very heavy, consists of a rusty substance, and exhales a strong 

 chalybiate smell ; at right angles to the above there are other splits. At one place, where 

 the beach is formed of decomposing rock, a ledge about 6 inches high and 2 feet broad runs 

 out and dips below the water ; originally it was probably harder than the rest but is now 

 soft. It has a whitish and yellowish red colour. Felspar predominates in this neighbour- 

 hood. On the beach altered fragments are strewn. Some are large rounded blocks, which, 

 internally, are of a deep brick red colour. The shore of the next point is strewed wilh 

 blocks of various sizes. Further in there are large raasses, of which some are broken. The 

 Point is the rounded extremity of a low hill (or one of the flanks of the range of the 

 Island) which rises from the beach. Piles of rock are partially seen through the jungle on 

 the hill side. From the W. angle I ascended the slope. A few yards up there is a remark- 

 able mass of rock partially split. The SW. portion, is in its general ontline, as viewed 

 from the SE., a pyramidal block, separated on the NE. from the rest of the mass by an 

 irregular chasm , and, where its base rests on the mass below, also fissured. Its face is grey 

 with lichens and mosses, and so rough with channels as to appear wholly wrinkled. The 

 channels face the SE. and are mostly inclined to the NE., but they are frequently irre- 

 gular, curvilinear, or slightly sinuous. The rock is a syenite, consisting of felspar, dark 

 green hornblende and quartz , — the first greatly in excess. 



At the bottom the syenite changes abruptly into a greenish black hornblendic semiflinty 

 substance, similar to that of P. Sejahat. At some places it is about 2 feet thick. This was 

 probably the thickness all along the base originally. The fissure between this block and the 

 mass on which it rests runs through this substance, as the upper surface has in some places a 

 thin coating of it. It is broken with great difficulty. I hammered at the edges for some 

 time with no other effect than to knock off the thin coating of decomposed rock , and had 

 •to be satisfied with fragments of some small rhomboidal masses which I found loose in the 

 fissure of junction. The rock decomposes at the surface into a soft yet tough greyish pow- 

 dery substance. The line of junction between the hornblende and syenite could not be mi- 

 nutely examined on account of the weathered state of the surface. I succeeded in knocking 

 off one small specimen at the junction. In this the black flinty rock first passes into a 

 greenstone , then the grey felspar increases till the hornblende appears in cloudy spots , 

 streaks and grains, dispersed in a base of felspar. Then in this compound base, crystals of 

 felspar appear. The number of crystals increases till the base entirely disappears. The pa- 

 rent mass is of great size, stretching from the fissure which divides it from the block describ- 

 ed above to the SE. Eeyond this it turns to the NE. and exposes a high perpendicular 

 face, of which the upper half is deeply channelled, and the summit broken into irregular 

 sharp pinnacles , — the terminations of the ridges that separate the channels. One of the 

 channels, the second from Ihe SW angle, reaches a little lower than the others gra- 



