least — o£ hard and compact rock; but tlie lower tracts are 

 composed of gypsum beds, and may be studied in the railway 

 cuttings. The secondary rocks thin away, and leave the funda- 

 mental strata entirely exposed at about ten miles south from 

 Farina. 



Eedhill. — At this Eailway Station a large reservoir has been 

 excavated in a very stiff and consolidated clay, probably derived 

 from decay of the fundamental rocks in situ. 



Leigh's Creek. — For a short distance north, and near this 

 Eailway Station, the rocks appear to dip at an inclination of 

 about 65° north-easterly. Xorth of Beltana the dip is south- 

 easterly, and a short v ay south of the Eailway Station the dip, 

 which has greatly decreased, is again north-easterly. Here 

 the beds exhibit a dusky purple colour and flagstone structure ; 

 indeed, so much so does the stone seem to partake of the latter 

 quality that I am persuaded excellent flagging is procurable 

 from them. Marble of no mean quality outcrops over the 

 surface of the little rise between the Eailway Station and the 

 township, and abounds in the neighbourhood. The Eailway 

 Station has been chiefly constructed of a blue marble, and 

 although some few of the blocks in the building might be con- 

 sidered by experts to be somewhat argillaceous, the bulk is 

 exceedingly pure, and capable of retaining a very fine polish. 



Black Eock Platx axd Tekowie. — Bounded at no great 

 distance on either side by the Black Eock Eange on the east 

 and the Pekina Eange on the west, as 9, natural consequence 

 the drifts constituting the whole of the Black Eock Plain may 

 pretty safely be looked upon as being water-bearing at iio great 

 depth from the surface. In the township of Terowie, west of 

 the railway, Mr. Harrison, the miller, informed me that he 

 obtained a plentiful supply of water in the Drift, immediately 

 overlying a ferruginous cement, at the depth of a little over 

 60 feet. The water is passably potable, and was used last 

 summer by many of the neighbours to a large extent ; in short, 

 its having been in use for steam purposes for a period of over 

 three months, without chipping and cleaning the boiler, is pretty 

 sure indications of its potable qualities. On the eastern side 

 of the railway, and about one-quarter of a mile distant from 

 the site of Mr. Harrison's well, the railway reservoir has 

 exposed in the Drift a similar bed of ferruginous conglomerate 

 about three feet in thickness at about 12 feet below the surface 

 of the plain. 



Tarcowie. — About two miles west of Yarcowie Eailway 

 Station, on the property of Mr. Alexander Mitchell, the slate 

 rocks dip at an inclination of about 70° westerly, the strike 

 being from 16° to 20° east of mag. north. Interlaced with 

 these slaty beds a prominent reef of very hard crystallized 



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