Yol. 55.] STRTJCTIJEE OP THE SOTJTHEEN MALVEENS. 131 



l)y the Cambrian shales. For descriptive purposes this may be 

 spoken of as the ' Western Tract.' Its surface is greatly diversified, 

 owing to the presence of a number of intercalated bands and in- 

 trusive bosses of andesitic basalt and diabase, as well as by the 

 inclusion of several faulted blocks of May Hill Sandstone. These 

 masses form a series of continuous or interrupted ridges or eleva- 

 tions, standing out more or less clearly from the surrounding lower 

 ground. Some of the gentler elevations are capped or flanked by a 

 stratified Drift of local origin. The district is, moreover, broken up 

 by two small valleys, one running from the Hollybush Pass west- 

 south-westward, and the other from the village of White-leaved 

 Oak south-westward. 



The tract is partly under cultivation, and partly used as pasture- 

 land ; much of it towards the south, however, is occupied by 

 woodland. The soil, in accordance with the varied petrographical 

 character of the rocks, varies greatly in character, but is for the 

 most part of rather poor quality. 



III. The Malveris^ Ran^ge. 

 (1) Raggedstone Hill. (Figs. 1-7.) 



It is proposed to examine first the structure of Raggedstone Hill, 

 because it is here that the mutual relations of the various rock- 

 masses are best shown. 



The hill is approximately triangular in outline, and is divided 

 throughout its length by a curved depression running from north to 

 south right across its centre, two distinct summits being thus formed, 

 each of which attains a height of over 800 feet (see PI. XIY). 

 iS'orth of the summits the depression broadens out north-north- 

 eastward, and forms a hollow known as Winter Combe. On the 

 south, too, the depression widens, as it curves south-eastward. 



This depression marks a line of dislocation, as already shown for 

 part of its course by HoU,^ and by Mr. Rutley.^ The former points 

 out that the character of the rocks and the strike of the schists 

 difi'er in the two halves of the hill. In Mr. Rutley's map this 

 fault is represented as terminated by a transverse fault on the south ; 

 but I shall in the sequel give evidence to show that it probably 

 runs the whole length of the depression. 



That portion of Raggedstone Hill which lies east of the depression 

 is formed by a mass of Archaean rocks : this, according to the two 

 authors named, is divided by faults into three main blocks. I 

 think it probable that a fault cuts off" a fourth component block, 

 forming that part of the eastern side of the hill nearest the large 

 quarry on the Hollybush Pass. I have not attempted, however, to 

 represent these faults on the map (PL XIII), believing that the 

 structure of the Archaean mass can be satisfactorily ascertained only 

 :after detailed mapping and petrographical study of the complex, 



^ Quart. Journ. G-eol. Soc. vol. xxi (1865) p. 75. 

 '^ Ibid. vol. xliii (1887) p. 488. 



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