5 



TV'liicli are worked locally, andfurnisli the building stone, flags, 

 and road metal required in the neiglibourhood. 



Two miles south of the town the pyritiferous slates form a 

 laard brown ferruginous shale, which constitutes a round-back 

 swell of about half a mile in length. This change is probably 

 due to the oxidation of the pyrites as they at times are found 

 studding this rock like currants in a cake. The same rock is 

 seen m the Light channel, about three miles below Hamley 

 Bridge, and from it I have gathered pyrites which, while ex- 

 ternally of a clear black colour, were of the original brass 

 yellow towards the centre. At several other places the shale 

 •occurs on the alignment of the slate, among others at Dorring- 

 ton's farm on the Marrabel range, where it is scarcely one 

 hundred yards from the unaltered bed. Paddy's Knob (in th(5 

 Northern Areas) on the G-ermein road near Wirrabara is 

 :another instance of this localisation of chemical changes. 



The two upper beds of this group contain much soluble 

 matter, and when treated with hydrochloric acid the pink 

 variety loses one-third of its weight. Their soft, almost friable, 

 nature and susceptibility to chemical action is the cause of 

 their always weathering into rolling swells with sometimes 

 deep watercourses at their bases. North-east of Tarlee the 

 valley is deeply cut up from this cause. 



About four miles east of E-iverton a fault of upthrow occurs, 

 which brings the lowest beds again to the surface. The beds 

 appear to be somewhat thicker also, which, though doubtless is 

 the case, is yet made more apparently so by the dip of inclina- 

 nation being lessened several degrees. 



The Marrabel range presents its steepest face to the west, 

 and has undergone denudation in a very irregular manner, due 

 principally to the varying hardness of the Tertiary sandstone 

 by which it is capped. The blue flags are seen at the fault 

 which passes by Ettrick's ruined church. The olive green slates 

 occur at the foot of the range ; the brown quartzite at intervals 

 shows bare on its summit, and half-way down the other side 

 is a quarry in the pyritiferous blue bed which has supplied the 

 •stone to build Marrabel. The next four miles is covered by 

 the Tertiary sandstone, and the sequence of the rocks is ascer- 

 tained by wells and exposures of rock at greatly denuded 

 points north and south of the sectional line. 



Another fault in this upper group of rocks is marked by the 

 Julia range. From here to the table-land the strata are mucb 

 disturbed and occasionally the angle of dip is very high' and 

 always easterly. The table-land range, however, dips westward, 

 and must therefore form a synclinal trough under the upper 

 portions of Julia and Pine Creeks. The eastern face of the 

 table-land presents a steep and sometimes bluff face, over- 



