410 Proceedings. 
of electricity, the latter of which, a comparative quality, 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 fur the 
currents discovered to exist in such veins by Mr. E. Fox some forty years ago 
might be produced by the gradual oxidation of mixed sulphides, and that veins 
containing bands of different metallic sulphides, 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 summary of the views on this subject prevalent a few 
years ago is given in Professor Hochstetter’s valuable work on this colony, in 
winch 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 + Vol. IV., Art. IL1 
