410 Proceedings. 



of electricity, the latter of which, a comparative qualit^f, he suggests might be 

 usefully employed as a preliminary test in the analysis of mixed minerals. 



The attributing of this property of generating voltaic currents, hitherto 

 supposed to be almost peculiar to metals, to such sulphides as are commonly 

 found in metalliferous veins, further led Mr. Skey to speculate how far the 

 currents discovered to exist in such veins by Mr."^! Fox some forty years ago 

 might be produced by the gradual oxidation of mixed sulphides, and that veins 

 containing bands of different metallic suli)hides, bounded by containing walls 

 and saturated with mineral waters, may constitute under some circumstances 

 a large voltaic battery competent to produce electro depositions of metals, and 

 that the order of the deposit of these mineral lodes will be found to bear a 

 definite relation to the order in which the sulphides rank in the table of their 

 electro-motive power. 



It is quite unnecessary for me to point out that these researches have a 

 most practical bearing on our knowledge of the conditions under which 

 precious metals will be found, and when applied by geologists may yet lead to 

 some clearer comprehension than we at present possess of the law which regu- 

 lates the distribution of auriferous veins, and why in some cases the metal 

 should be nearly pure^ while in others it is so largely alloyed with silver. 



There are many other subjects, to which I cannot at present refer, on 

 which Mr. Skey has advanced our knowledge, such as the investigation of 

 the poisonous matter of the tutu, karaka, and other indigenous plants, the 

 formation of coal seams, and other matters of interest. 



As being a subject of general interest at the present time, in the discussion 

 of which many of our members who have not much taste for technical science 

 can take part, I wish now to refer to the state of opinion relative to what we 

 must term the pre-historic period of New Zealand. 



A most complete sumviary of the views on this subject prevalent a few 

 years ago is given in Professor Hochstetter's valuable work on this colony, in 

 which he adopted the conclusion that the Maoris first arrived in New Zealand 

 about 500 years since, and gradually spread over the country, altering the 

 surface features considerably, and, for instance, among other changes effected 

 the extermination of the Moa, which, from the authorities he quotes, he 

 supposes to have survived to about the middle of the seventeenth century. 



I do not feel competent to judge of the extent to which Mr. J. T. Thomson's 

 paper in the last volume of the Transactions modifies the previous opinions held 

 respecting the origin and migration of the Maori race,"^ but his paper, and also 

 the critical paper by Mr. Travers,t on the value of native traditions as evidence, 

 appear to indicate that the subject is still open to discussion, and I am glad to 

 learn that during our meetings this season we may expect several communi- 

 * See Trans. N.Z. Inst., Vol. IV., Art. L f Vol. IV., Art. II. 1 



