570 /. B. SCRIVENOR 



scale, and the suggestion is strengthened by vertical limestone cliffs 

 overlooking the granite of the Kerbau Coulisse, by small patches of 

 phyllites lying between the base of these cHffs and the granite, and 

 by a brecciated iron-ore deposit at the base of one of the hills. In 

 Perhs again a double Hne of Hmestone hills runs north and south 

 through the center of the state, rising from shale and quartzite 

 country, but here there is a possibiUty of the latter being older than 

 the limestone. In other states I have not seen any evidence of 

 faulting having formed blocks which denudation has converted into 

 limestone hills. I may mention in this connection that Dr. W. C. 

 Klein, who has studied the geology of northern Sumatra, where 

 limestone hills also occur, tells me he considers that faults are of 

 structural importance and affect the limestone. In Borneo also, 

 the late Mr. J. S. Geikie attributed the formation of the hmestone 

 hills of the gold-bearing area of Bau and Bidi in Sarawak to faulting.* 

 I have seen the limestone hills at Bau and Bidi and found the 

 evidence of faulting determining their formation very strong, and 

 clearer than in the Kinta District, where the earth-movements have 

 been more intense. 



In Sumatra Dutch geologists recognize earth-movements later 

 than the Mesozoic folds. In the Peninsula these are marked by 

 faults in the granite, and in some places, as in Negri Sembilan, by 

 shearing of the same rock, but they are not known to be of any 

 structural importance. 



' J. S. Geikie, "The Occurrence of Gold in Upper Sarawak," Trans, of the Inst, of 

 Mining and Metallurgy, Vol. XV (1905-6), pp. 65, 66 and Fig. i on p. 65. 



