260 



Memoir on the Geology of the 



[Oct. 



oxide of uranium ; at others, golden, scarlet, red, or, lastly, it has a 

 jet black, velvety enduit (No. 40). The titaniferous iron has a senii- 

 conchoidal fracture — the lustre is adamantine, and, in some of the spe- 

 cimens, glimmering — it scratches glass—alone is infusible before the 

 biowpiye, but forms with borax a reddish globule, in which the par- 

 ticles of the metal are still seen, changed into the same colour — not mag- 

 netic, even after the action of the blowpipe. These two last qualities, 

 together with the probability of its containing uranium, would make this 

 metal approach to nigvine or iserine, more than to menaccanite. Judg- 

 ing by what we see in the bank of the road, this metal cannot 

 be scanty in quantity. In this locality I also found two pretty large 

 loose pieces of an iron ore apparently different ; fracture scaly — it 

 shines brilliantly— is powerfully magnetic, and looks like chromate of 

 iron (No. 41). 



Leaving this titaniferous vein, and descending towards the farm, hav- 

 ing reached a little flat in the road, we see many masses of horn- 

 blende rock, which, having been blasted to form the road, show the 

 thick quartz veins of a bluish colour, traversing the rock in all direc- 

 tions (No. 42). 



If observations and facts were wanting to prove that the thick mass 

 of liihomargic earth is owing to the decomposed granitic rock of these 

 hills, the following is conclusive. The original undecomposed rock is, 

 as I have said, traversed occasionally by thick veins of quartz. These 

 •veins resisting decomposition (which affects the remainder of the 

 ingredients of the rock) are seen in a continuous course, penetrating 

 from the hard crystalline undecomposed nucleus of the rock into the 

 lithomargic earth, and into the concentric layers of the already decom- 

 posed rock. Therefore, it is impossible to avoid the conclusion, that 

 the red earth and the rock were, at one time, one mass, traversed by 

 the quartz vein, which is still seen continuous and entire, notwithstand- 

 ing the transformation of one-half of the rock into red earth. This is 

 to be seen on the N. bank of the road, which descends from Ootaca- 

 xnund to Kaitee valley, after the steepest descent of the Kaitee pass is 

 finished ; and, I dare say, may be found in many other places, which 

 I have had no opportunity of visiting. What I have said of the quartz 

 veins is also applicable to the more numerous felspathic veins, which 

 traverse the rock ; with this difference, that they are decomposed, and 

 converted into porcelain earth, while those of quartz are entire and un- 

 changed. But the continuity of the vein is evident, although one-half 

 of it has changed nature. 



At the end of the descent, a little way to the right of the road, there 

 are the ruins of what were the Artificers' huts. Here are to be seen 

 many straggling pieces of quartz iron ore (No. 43), and many large 

 masses of the same implanted in the ground. In these last, the rock is 



