226 



PROCEEDINGS OF SECTION C. 



containing irregular nests and masses of blue and green carbonates, 

 which lead, however, to lodes in depth. The Cobar and Nymagee 

 copper is associated with Silurian rocks, and in New Zealand 

 some exceedingly irregular deposits occur in serpentine, but have 

 not been successfully worked up to the present time. 



The deposits of coal vary quite as much in their geological 

 age as those carrying gold. Those which are worked in New 

 South Wales, the premier colony in this class of mining, are in 

 the Upper Carboniferous and Permian rocks. Three distinct 

 belts of coal-bearing strata occur, separated from one another by 

 some thousands of feet of barren rock. The upper and lower 

 beds contain the best coal, but good workable seams also exist in 

 the middle group. The quality of the coal also differs in different 

 parts of the colony, and whereas the Newcastle coals are of a 

 good, all-round, character, with a comparatively small percentage 

 of ash, and are of a caking nature, those of the Illawarra district are 

 pre-eminently steam coals in which the proportion of ash is their 

 only bad feature, whilst the Mountain coal is of a free burning 

 nature, non-caking, and with a large percentage of ash. Some of 

 the coals of Queensland, e. g. that of the Burrum field, belong 

 to the same formation as those of New Soutli Wales, but those 

 of Ipswich appear to be younger. The coals of Victoria are in very 

 small seams so far as proved, and appear to be of Oolitic age, 

 while those of New Zealand, on the west coast, are Cretaceous 

 where the quality is all that could be desired, forming an excellent 

 coke, yielding a large percentage of gas, and, especially those of 

 Westport, being excellent steam coals. 



The lignites and brow^n coals of New Zealand are possibly 

 somewhat younger than the bituminous series, and the coals are of 

 a very inferior quality, but still have a fair local consumption ; 

 while the Bay of Islands coal, which is semi-bituminous, forms an 

 excellent steam-coal, and has had a large sale for ocean-going 

 steamers. 



The very large annual output in New South Wales has necessi- 

 tated the opening of the mines on an extensive scale and the 

 employment of winding and hauling machinery on an improved 

 principle. In the Newcastle district there is perhaps little to be 

 desired in this respect in the principal mines, and an output of 500 

 tons a day is arranged for in several collieries. The underground 

 haulage is chiefly carried on by the tail-rope system ; each colliery 

 is connected by rail with the port, and the Government have 

 provided ample wharf accommodation, and hydraulic cranes by 

 which the vessels are loaded with rapidity. In the southern 

 collieries the coals are mostly worked either level free, or by dip 

 drives, and many of the mines own private wharves which are 

 connected with the mines by private railways, or self-acting trams, 

 so that, when not prevented by stress of weather, the loading is 

 also rapid. 



