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STANNIFEROUS DEPOSITS OF TASMANIA. 



By S. H. Wintle, Esq., Hobart Town. 



[Communicated by the Rev. W. B. Clarke, Vice-President. Bead 7 July, 



1875.] 



1. Mount Bischoff. 



Although much has appeared through the channels of the 

 public Press respecting this remarkably rich tin ore bearing region, 

 nothing that I am aware of has emanated from a reliable geo- 

 logical source as giving a detailed description of the structure of 

 the mountain and the occurrence of the ore as a contribution to 

 the Proceedings of the Eoyal Society of New South Wales. 

 Under these circumstances I am induced to offer the following 

 remarks, which are in accordance with the evidence presented by 

 specimens of rock and ore collected during a residence of several 

 months, in the hope that they may prove acceptable to the Society. 



Mount Bischoff is situated about midway between the north- 

 west coast and the west coast of Tasmania, with Bass's Straits on 

 the one hand and the Pacific Ocean on the other. "Were a line 

 drawn from Emu Bay to about midway between Macquarie Har- 

 bour and the mouth of the Pieman Biver, it would bisect Mount 

 Bischoff, and thus form a base line of a nearly eq uilateral triangle 

 with Cape Grim. Erom Emu Bay — the nearest place of ship- 

 ping — the Mount is distant about fifty miles by the road, which 

 passes through a densely-timbered country, consisting chiefly of 

 large native myrtle, pine, and sassafras trees, with a thick under- 

 growth of tree-ferns and various smaller species of the same, and 

 through which at intervals, especially in the gullies, almost im- 

 penetrable belts of the "horizontal" of the early surveyors (the 

 Anadopetulam biglandulosum of the botanist) obtain. Here and 

 there this dense vegetation is relieved by patches of more open 

 gum-tree country. [A very similar description was given by Mr. 

 Gould. W. B. 0.] 



Along the north-west coast, for upwards of a distance of seventy 

 miles, the older palaeozoic rocks are exposed at intervals by the 

 action of the waters of Bass's Straits. These consist of lower 

 silurian and still older Cambrian transition strata, all highly in- 

 clined, — indeed, in many instances, so much so as to be nearly 

 vertical, while they are folded and contorted to a remarkable 

 extent. These are chiefly clay slate, altered sandstone, limestone 

 conglomerate, and quartzose rock, and which are much traversed 



