478 Transactions. — Geology. 



The cbajacter of these vemstones is very similar, both in appearance 

 and in mode of occurrence, wherever they are found, except that in some 

 places the vein is only a few feet wide, whereas in others it may be thu-ty 

 or forty feet thick. If we find a similar result to that already obtained 

 from several different localities, we may then, I think, conclude that we 

 have valuable mines in the district. I know a great many places in which 

 these veinstones are found, and will now j)roceed to describe them. 



These reefs appear to me to be found chiefly along two lines, and run 

 in the direction of the ranges — viz., about N.N.E. and S.S.W. The 

 western line intersects the upper part of the Otaki Eiver, and that of the 

 Hakatarewaha, and probably appears in a confused and undefined state at 

 Baker's Hill, near Wellington. 



The eastern line appears to strike up the valley of the Orongorongo, 

 in which locality the specimen under discussion was found. There is 

 a reef of this stone on Sinclair's ground in the upper part of the Wainuio- 

 mata, and there are indications of it about Drake's Elbow on the Eimutaka 

 road, all pointing to the general direction of this line. 



The widest reef which I have seen is situated on the banks of the 

 Waiotauheru, a branch of the Otaki Eiver. It is a long time since I have 

 seen it, and therefore do not like to speak positively as to the dimensions, 

 but I think I should be safe in calling it at least a chain wide. 



In the upper part of the Hakatarewaha I found a reef about four feet 

 wide. 



On the western line I think that attention should first be directed to the 

 valleys of the rivers above named, particularly as there is now easy access 

 to the valley of the latter river. 



To reach the reefs of the Otaki Eiver cannot be an easy matter at this 

 time of year. It is difficult to give an exact idea of the distance to be 

 travelled, but an estimate may be formed from the length of time it took 

 me to reach them. From the Wairarapa pa, near the point where the 

 Otaki Eiver leaves the mountains, it took me a day and a half walking 

 to reach the reefs. In returning down stream it was an easy day's joiu'ney 

 to reach Otaki itself. 



When the base of the higher part of the ranges is reached, the Otaki 

 Eiver is found to fork. The main stream comes down from the northward, 

 and a large tributary called the Waiotauheru falls in from the southward. 

 About two hours' journey up the latter river I pitched my camp, and near it 

 were the reefs in question, cropping out on the right bank of the river, and 

 standing vertical. 



The character of these reefs is typical of all the others of the same kind. 

 The quartz stands in lines of three or four inches thick, separated by 

 mullock. The quartz veins have an undulating conformation, chain-like, so 



