354 Transactions. — Geology. 



Auckland Mechanics' Institute on the 24th June, 1859, said, 

 " The first striking characteristic of the geology of this pro- 

 vince — and probably of the whole of the Northern Island of 

 New Zealand — is the absence of the primitive plutonic and 

 nietamorphic formations, as granite, gneiss, mica-slate, and 

 the like." Sir James Hector, in his " Outlines of New Zea- 

 land Geology," observes that schists and metamorphic rocks 

 are unknown in the North Island. 



The oldest rocks hitherto known to exist in this Island 

 were certain hard splintery greywackes and slaty shales which 

 form the greater portion of the Tararua, Euahine, and Kaima- 

 nawa Eanges, in the Province of Wellington. The same rocks 

 also occupy smaller isolated areas at Tuhua, Taupiri, and 

 Hunua Eanges, and form the basement rock of the Hauraki 

 Goldfields. In the absence of fossil remains, their age has 

 always been a matter of much uncertainty, but they have 

 generally been placed by geologists in the Carboniferous 

 period, mainly, it would appear, from a lithological likeness to 

 some rocks ascribed to that period on the south side of Cook 

 Strait. 



The circumstances which led to the recent interesting dis- 

 covery of granites and other crystalline rocks in this Island 

 are briefly as follow : Last March Mr. Max von Bernewitz, 

 the well-known assayer to the Bank of New Zealand at the 

 Thames, showed me, in his melting-room, some fragments of 

 rocks which had been forwarded from the King-country by 

 Mr. G. T. Wilkinson, J. P., Government Native Agent, for the 

 estimation of the gold which they were believed to contain. 

 Among the rocks I at once identified examples of true granite 

 and a granitic gneiss, and at the same time expressed some 

 doubt as to their belonging to any part of this Island. Mr. 

 T. L. Murray, the general manager of the bank, who always has 

 shown the keenest appreciation of geological facts and pro- 

 blems, at once placed me in communication with Mr. Wilkin- 

 son, with the result that at Easter I visited and examined the 

 locality where the specimens were found, acting upon in- 

 structions received from the Hon. the Minister of Mines, by 

 whose permission I am now enabled to place the facts of this 

 important discovery before the society. 



On my arrival at Otorohanga I found that the rocks re- 

 ferred to were accidentally discovered by Mr. Charles King while 

 mustering his sheep in the Mangaone Valley. Judging from 

 their great weight and colour, he thought them likely to con- 

 tain gold ; and, aided by Mr. Arthur Ormsby and Mr. Grif- 

 fiths, of Alexandra — the latter an old alluvial miner — the 

 locality was diligently prospected, and one or two " colours" 

 are said to have been found in the wash in the bed of the 

 Mangaone Stream, while some fragments of granite, which 



