lY. — CHEMISTRY. 



Art. XIjIY. — Notes upon the Mineral Oils of New Zealand. 

 By William Skey, Analyst to the Geological Survey of New Zealand. 

 [Read before the Wellington Philosophical Society, IQth Januai-y, 1874.] 

 Abounding, as this colony does, in carbonaceous deposits, mineralized through 

 all the stages of lignite, brown coals, bituminous coals, and anthracite, it is 

 only reasonable to suppose that mineral oils should also occur in it ; and 

 indeed oils of this nature have long been known to exist here in small 

 quantity, as films upon the surface of the water of certain springs, or wells 

 sunk to a little depth ; but it was only in the year 1866 that the attention of 

 those in a position to give it effect was directed towards ascertaining the 

 precise character of these oils, and the prospects of their occurrence in 

 quantity.* 



In that year samples were forwarded to the Colonial Laboratory for 

 analysis, both fx'om the eastern and western sides of the North Island, and the 

 results of their analysis, together with geological reports upon the nature of 

 the country where they were procured, were duly published in the Annual 

 Report for 1866-7, issued by the Geological Survey Department. 



Since then further samples have been examined by me from the East Coast, 

 and, though the results obtained upon them have been furnished to the persons 

 by whom they were respectively contributed, and have been besides published 

 in a brief manner in our local papers, still I do not think they have that degree 

 of publicity which the importance of the subject demands for them ; nor yet do 

 I think they have that degree of concentration necessary for their easy 

 comprehension by anyone anxious to learn them, as they are interspersed 

 throughout so many pu.blications. In the hope, therefore, of putting all that 

 has been elicited concerning the nature of these oils in a form suitable for 

 those anxious to be informed on this matter, I have prej)ared this paper. 



Before I enter further into this subject I will remind anyone av^Iio may 

 need it that these petrolevims are simply hydrocarbons, or hydrogen in com- 

 bination with carbon in different proportions, and every petroleum is a mixture 

 of a great number of such hydrocarbons ; and generally, according to the 

 proportion of hydrogen to the carbon of any petroleum, so is its density. As 



* N.Z. Gazette, 29tli Juxie, 1866. Geol. Kept., 1866-7, p. 8. Col. Mus. aucl Lab. 

 Eepts., 1867, p. 19. 



