nUBTDGE — ROCKS OF THE CAPE TOWN DISTRICT, 



contitiuoiis with tho Zwarteberg rango, which I believe to be Devo- 

 nian, I should consider them also of the same age." — Ihid., pp. 585- 

 587. 



Mr. Wi/lie, Government Geolor/icnl Sarvei/or. — " irere" (at Goobe- 

 loan's northern base of the Zeurberg) "the shales disappear, and we 

 enter upon rocks exactly the same as the Wittenbergen and the Ko- 

 roo Poort sandstones in the western, district. These continue all the 

 way through the Zeurberg. Beside the yellowish or brownish sand- 

 stones there are many beds of very sandy shale, usually of a bright 

 colour. Many of the sandstones cannot be distinguished from thoso 

 of Table Mountain, though the latter are of much older date."* 



"The sandstones of the Zeurberg form a great anticlinal arch ; but 

 this consists again of three great folds and two or more minor flexures. 

 The beds may be seen dipping at all angles from 5° to 80°. On the 

 seaward side of the Zeurberg, between the 20th and 2lst milestones, 

 I again crossed the trap conglomerate on the southern side of the an- 

 ticlinal. It there forms a belt in width about 500 yards, and in actual 

 thickness is not more than 500 or GOO feet. Grey shales occur both 

 above and below it." — ' Notes of a Journey,' etc.. Cape Town, Saul, 

 Solomon, & Co. (See also p. 3 of the same, and passim.) 



There may be some little apparent confusion arising out of the 

 difFcrent nomenclatiu'e used by the authorities I have quoted. The 

 fact is, that the beds which are usually blue and clayey schists, with 

 some argillaceous sandstones, are generally altered to a micaceous 

 chloritic or talcose character, and in the upper part, when mixed with 

 the sandstones, are ochry. The spots 

 in which Devonian fossils have been 

 found, together with the uniformity of 

 strike, prove their identity throughout. 

 This is now admitted by all observers 

 as to this province. Fig. L— Section of Pickel Vontein. 



The sections sent herewith are:— (Athcrstone and llubidgc.) 



1. Pickel Vontein, carefully observed by Dr. Atherstone and myself. 



2. Chatty, measured by ]\Ir. Pinchin and myself. 3. Section through 

 Klein Poorden Poort, by Mr. Pinchin and __.-^rv 

 myself. These have been merely sketched I'fl'iii'iii] 

 without measurement in the present in- ill ^ jl 

 stan?e, aa I am unfortunately deprived of |; 

 ^Ir. Pinchin's valuable aid. A carefully exe- 'lill; 

 cuted section was sent home to the Geologi- 'I Il - 

 eal Society some years ago. I ; i ;,' 



I will conclude this paper by showing that Fig. 2. — S«'(;liontliionu;h("h;i(ly. 

 what 1 have, I hoj)e, satisfactorily proved of (Piufhin aiul Rubidgc.) 

 the (piartzite, is ahio predicable of crystalline limestone or marble — vi/. 

 the conliiiuity of horizontal beds unconformable with, the subjacent 

 strata, with beds of the sanu^ kind intercnlatcd between the latter. 



* Mr. Wylic, ill Iris section of this part of the Colony, which, thoiigli not pnblislicd, is 

 phiccd in tlic 'rowii Hall, in Cape Town, makes the shales above spoken of conformable 

 willi llie sandstones. 



