56 MR. D. DRAPER ON THE MARBLE BEDS OF NATAL. [Feb. 1895, 



5, and finally. Since the marble-beds were placed in their present 

 position they have been extensively eroded by the rivers, 

 which have deepened their courses to their present level ; but 

 the numerous pebbles and boulders found along the hillside 

 (more especially at the spots marked E in figs. 1 & 2, 

 pp. 52, 54) are evidences of these rivers having occupied a 

 much higher line at a comparatively recent date. 



Note. — The Cretaceous beds of the Umtamfuna river are about 

 30 miles south of the locality where the marble occurs. 



Discussion. 



Dr. Du Eiche Preller regretted that the paper appeared to 

 contain no suggestion whatever regarding the probable age of the 

 granite and marble respectively, nor any indication that the contact- 

 lines had been examined to determine the relation of these rocks to 

 each other. The two sections given in illustration of the occurrence 

 were contradictory ; for while in one section the marble rested like 

 a sheet or mantle on the granite-masses, in the other the marble- 

 mass was wedged in between the granite. In the first section the 

 marble appeared, as the Author concludes, ' deposited ' : that is, it 

 would be compact limestone subsequently rendered crystalline by 

 lateral or superincumbent pressure ; whereas in the other section 

 the granite below and above might be the remains of a fold such as is 

 met with in the schists and marble strata of the Carrara district. 

 Seeing that the marble was stated to contain about 15 per cent, of 

 magnesia, it seemed to be of a dolomitic nature rather than strictly 

 saccharoidal limestone like Carrara marble, which latter contained 

 at least 93 per cent, of carbonate of lime. 



Prof. T. Rupert Jones also spoke. 



