292 ON THE TRANSMUTATION OF ROCKS, &c., 



Hawkesbury rocks at the junction of the two series, and have 

 hardened and altered both at the points of contact. 



On Razorback, northern ascent, the plant-bearing calcareous 

 grits have in one instance become completely spheroidal near a 

 trap dyke and in its line of direction. 



On the south side of Razorback, near Picton, there is a deposit 

 of very curiously structured carbonate of iron, a yellow cone-in- 

 cone ore, an effect of transmutation, and satisfactory enough as to 

 my views of the age of the deposits in which it occurs. I have 

 specimens of identically the same ore from the Maranoa and Flin- 

 ders Rivers, in Queensland. 



At Prospect Hill, an old dioritic summit has been surrounded 

 by the Wianamatta deposits, so that it rises through them like 

 an island. Portions of disintegrated and regenerated sedi- 

 mentary dioritic matter form some of the beds, which contain 

 casts of plants. Through these and the other beds, basalt full of 

 chrysolite has subsequently risen and formed a coulee with 

 columnar structure, on the north-east extremity, and this has 

 transmuted the Wianamatta shales in some places into a greenish 

 jaspery substance. 



On the east of Paramatta, about half way to Sydney, a mass 

 of columnar basalt has risen through the lower Wianamatta beds, 

 and from this Sydney is supplied with road metal. About 

 twenty-five years ago there was visible on the flanks of this mass 

 a series of parti- coloured aluminous beds, inclined to the basalt, 

 which have been destroyed in the process of excavation ; but I 

 was fortunate enough to make a coloured sketch of them whilst 

 they were in existence. The prismatic structure here is partly 

 curvilinear and partly vertical. Between the prisms occur lumps 

 and strings of calcareous spar, and the outside of them is covered 

 with a greenish talcose-looking substance, of a fibrous texture, so 

 much resembling woody fibre, that it has deceived even botanists 

 in that respect. Now this substance, in fact a mixture of the 

 ordinary basalt with lime, is, I conceive, an effect of transmutation. 

 It is by no means unusual to find such products of basalt. 

 Whether the lime has been derived from the calcareous matter in 

 the Wianamatta beds, or comes from an independent source, it is 

 perfectly in accordance with numerous examples in other parts of 



