1182 GEOLOGY AND PHYSICAL GKOGRAPHY OF THE STATE OF PERAK, 



feet at a rough estimate. I think this mountain is the one known 

 as Gunong Robinson. From it the range declines, but is still a 

 bold series of picturesque peaks, many of which must be over 

 6000 feet high. Other higher points are said to be occasionally- 

 visible in the south-east. It is possible that geologically the main 

 range is younger than the groups already referred to. 



IDEAL SECTION. 



The following is a description of a section through the State 

 from east to west, in about the latitude of Thaiping. 



Proceeding westward from the Straits of Malacca we meet : — 



1. Alluvial mangrove flats. 



2. Light quaternaxy drifts with much vegetable matter, granite, 

 sand and gravel, lying upon stream tin. 



3. Clays and partly decomposed schists and slates, sandstones, 

 red, yellow, ])lue and grey, commonly called Laterite, from the 

 brick red colour of some portions. This is a paleozoic stratified 

 rock, resembling in lithological character the Ordovecian or 

 Cambrian deposits of other countries. There are no fossils, and 

 as lithological character is by no means a certain clue, though it 

 has a considerable value in these older rocks, it will be under- 

 stood that I only provisionally refer the rocks in question to any 

 horizon, especially to the Ordovecian which in Australia and other 

 countries are so rich in minerals. 



4. Granite rocks of the first range which I shall here distinguish 

 as the Thaiping Range. 



5. Alluvial of the valley of the Perak River, consisting of drift 

 from the spurs of the granite mountains, and including stream tin 

 in the valleys formed by these spurs. It is uncertain if the 

 Cambrian deposits re-appear in this valley, but here we meet with — 



6. Detached outliers of a highly crystalline limestone with almost 

 perpendicular dip. 



7. A second granite range which I distingush as the Kinta 

 Range dividing the valley of the Perak River from that of the 

 Kinta. 



