Chap. IV. 2,] metamorpiiic hocks, 91 



with that just defined about three-fourths of a mile to the nortli, not 

 extending" so far west, hut reaching right up to the very hase of the 

 Shevaroys. The northern edge of this area trends to the north-east and 

 north for a distance of about 4^ miles, then suddenly turns sharply, runs 

 for nearly a mile south by east, and again bends to assume a south-east 

 coxirse. The eastern side follows the general curve of the south-west 

 corner of the Shervaroyen, against which it abuts. 



This larger area, like the smaller southern one, is rather elevated above 

 the general level of the country, especially along its northern edge, which 

 is formed in part by a succession of low hillocks rising about 100 or 120 

 feet. Towards the south-east the ground sinks into a broad valley, in 

 which rises the feeder of the great tank just outside of Salem, on the 

 Bangalore road. 



The greatest length of this area is 6| miles from west to east ; the 

 Mode of occurrence of g'^^^atest width, 5 miles from north to south. Over 

 veins. ^YiQ whole of the two areas thus described, mag- 



nesite veins occur in innumerable quantities, running in every possible 

 direction; the more imjjortant veins, however, as aheady mentioned, 

 follow certain definite directions, coinciding with the directions of joint 

 fissures observed in the unaltered gneiss rocks of the immediate vicinity. 

 Direction of principal ^he bearings of the principal veins taken by the 

 ^®"^^' compass were as follows : — 



N. N. E. 

 N. E. 

 N. E. by E. 

 E. N. E. 

 E. 

 S. E. 

 showing a general tendency to a north-east heading in the main veins • 

 but if the minor veins be taken into consideration, hardly a single point 

 of the compass would remain unrejjresented. 



( ol-3 ) 



