Page:Quarterly Journal of the Geological Society of London, vol. 25.djvu/396

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New South Wales, and Northern Queensland, nor copper-mines like those of Burra-Burra and the Peak Downs, nor in its sandstones valuable and extensive coal-beds like those of the Illawarra and Hunter-River districts. But no reason is apparent why all these, and perhaps other minerals, should not exist in this part of the range as in its continuation further south. Coal has been found as far north as Port Denison (lat. 20° S.), and gold and copper at the Peak Downs (lat. 23° S.), the former 200 and the latter 350 miles from the base of the peninsula, and they may extend well on towards Cape York. We must remember that this by no means insignificant portion of Australia has been very imperfectly explored, and, what is perhaps of greater moment as far as useful discoveries go, is very thinly peopled. True, Kennedy in 1848 advanced along the coast to the eastward of the main range nearly as far as Cape York, which goal the Jardines actually reached in December 1864, by traversing the more passable region to the west of the range; while Leichardt (1845) and A. Gregory made a slight detour into the western part of its broad base, on their westward way; but these explorers, for various reasons, had little time or opportunity for prospecting. The existence of mineral treasures is most frequently discovered by private enterprise, and often by the unscientific though practical hands of settlers. As yet, however, only a trivial part of the south-west region is occupied, and that scantily; while one rudimentary township of sixteen persons exists near Cape York. Thus neither the north nor the south is capable of furnishing men or money to investigate the extensive intermediate district, the barren character and treacherous natives of which are obstacles sufficient to deter all but the most resolute and well provided from attempts of this nature, and from engaging in labour the results of which are necessarily very uncertain.

The surface rock in the neighbourhood of Cape York, including Albany island and the vicinity of Somerset, consists of ironstone varying from a comparatively light friable clay-carbonate to a heavier dense ferruginous conglomerate, usually vesicular, honeycombed and channelled on its exposed surface from weathering. Its density and hardness differ with the varying proportion of iron. Sometimes it is nodular, very hard, highly metalliferous and magnetic. Under atmospheric and other physical agencies these nodules separate from the clayey matrix, and lie scattered plentifully over the surface in the form of rounded or oval pebbles, and small boulders having a dark metallic lustre. On the other hand the soil which is the principal result of this disintegration is fine-grained, dirty-red, and sometimes unmodified, but oftener mixed with coarse quartzose sand and vegetable mould, but in all cases scanty and poor. This circumstance, conjoined with the protracted droughts of the dry S.E. monsoon, lasting from eight to ten months, materially influences the character of the vegetation, which is stunted and undergrown, and seldom possesses the luxuriance we might expect within 10-1/2° of the physical and 8° of the thermal equator, except along the banks of the Polo, Mew, and similar paltry streams and