hill, separated by a deep and narrow valley, no continuity 

 can be traced between the two intrusions. Indeed, stratified 

 beds of limestone and decomposed shales can be traced almost 

 uninterruptedly across the dividing area. The beds are much 

 disturbed in their strike and angles of dip adjacent to the 

 igneous rock. There is a curious, and not easily explained, 

 relation between the igneous rock and the sedimentary 

 deposits. A limestone appears to go up to the centre of the 

 igneous dyke (or (?) sheet), in the centre of the line of strike. 

 The limestone has a dip E. at 70°, whilst the strike of the- 

 iofneous rock is N.E. 



Separated by a belt of rotten shales and quartzite flags, 

 100 yards in width, is another igneous dyke (or (?) sheet), 

 near to the road. Its composition is very distinct from those 

 previously mentioned, although on about the same line of 

 strike. At the north-east side of the hill there is a bold 

 outcrop of rock consisting of limestone and shale, closely 

 adjacent to the igneous rock. 



Following these igneous outcrops, in a westerly direction, 

 is Sandalwood Flat, about 1 mile in length, in which the 

 rocks continue mostly on the same line of strike. At the 

 northern end of Sandalwood Flat, and on the same side of 

 the road as the preceding, another igneous rock is seen in a 

 steep cliff in a creek. It has the same strike (N.E.) as the 

 smaller igneous hill, next the road, described above, and 

 possesses a similar rock texture. 



A second ridge, on the westward, rises to about 300 ft. 

 in height. The lower half of the hill consists of a hard 

 laminated and dark-lined quartzite: strike E. 20° S. at 90°. 

 The upper half of the ridge is a very close-grained igneous 

 rock, with features distinct from the two other varieties 

 already mentioned. 



Near the base of the ''Big Hill," on its eastern side, 

 an important basic igneous dyke is exposed on the road. Its 

 strike is, apparently, north and south, and is 34 yards wide. 

 It occurs in dolomitic limestone, which latter is somewhat 

 altered by contact with the intrusive dyke, and contains some 

 copper ores, as well as a very large mass of ferrugineous and 

 copper-stained quartz. 



There are thus five important igneous intrusions near 

 together and adjacent to the road on the Wirrealpa side of 

 the "Big Hill." I very much regretted that no opportunity 

 presented itself for - aking a more detailed examination of 

 this very interesting "igneous field. 



As the "Big Hill" is approached from the eastern side, 

 thick limestones appear on the eastern side of the road : dip 

 E. 20° N. at 15°. A sandstone occurs in the creek, with a 

 dip W. 20° S. at 55°. It is, apparently, included in the 



