﻿I860.] 



FORBES BOLIVIA AND PEBU. 



41 



reverberatories with two chimneys instead of one as generally used 

 for coal or wood. 



The mode of occurrence of the cupriferous deposits of Corocoro is 

 shown by the accompanying sketch-section (fig. 2), not drawn to a 

 scale, but affording a pretty good general idea of the main features of 

 this important mining-district. In this section the beds of cupri- 

 ferous sandstone which are known and worked are denoted by 

 continuous black bands, whilst those supposed to exist, but not yet 

 proved, are shown by interrupted black bands. 



Fig. 2. — Diagram-section of the Corocoro Copper-mines. 



12 3 Fault. 



1. Veta del Buen Pastor. 2. Veta de Eejo. 3. Veta Umacoia. 



In the centre of the section a great fault is seen bearing nearly 

 but not quite N.W., and dividing the whole metalliferous district into 

 two parts ; and on examination 



it was found to have produced Fig. 3. — Ground-plan of the Fault. 

 both a horizontal and a vertical 

 disturbance in the original po- 

 sition of the beds. Horizon- 

 tally, the beds which, if merely 

 broken and lifted up vertically 

 on one or both sides of the fault, 

 would naturally show parallel 

 lines of outcrop, do not so ; 

 but on the right hand or east 

 side of the fault they are skewed 

 round, so as to make an angle 

 of about 10° to the fault and 

 the outcrop of the beds on the 

 west side. This will be fully 

 understood by reference to the 

 annexed woodcut(fig.3),which 

 is supposed to represent a ground-plan of the present outcrop of the 

 lines of stratification on both sides of the fault, and will not require 

 further explanation. 



