470 Transactions. — Chemistry, 



As this substance, though clearly an alkaloid, does not yield any colour 

 reaction with oxidizing agents (such as chloride of lime), it is neither aniline 

 nor naphtha-aniline, and therefore is not derived from either benzol or 

 naphthahne, and so does not indicate the presence of these hydro-carbons in. 

 the oil tested. The alternative is, then, that it is derived from a hydro- 

 carbon or some hydro-carbons of the series which benzol heads and typifies, 

 and which is in all probability either touluole or xylole, or a mixture of 

 the two. 



Having obtained this result I extended my researches, and so have 

 ascertained that all the brands of American kerosenes which we have here, 

 together with the so-termed benzols, also contain hydro-carbons, which are 

 capable of yielding alkaloids to the process I have described (the aniline 

 process), but still give no colour reaction to oxidizing agents. 



Our own petroleums, both the heavy (Taranaki), and the light one 

 (Poverty Bay), as well as their distillates Hght and heavy, also behave in 

 this respect like the American oils. 



In the case of the Taranaki crude petroleum in particular, this series of 

 hydro-carbons is well represented — that is, quantitatively. 



The nitro-oil of this petroleum (the first product of the process employed), 

 when cleansed from the unaltered oil by repeated solutions in alcohol and 

 precipitations by water, has a sweet and powerful odour much resembling 

 that of nitro -benzol. 



The facts detailed above lead me to suspect that every petroleum contains 

 one or more representatives of the benzol series of hydro- carbons. Which 

 particular member of this group (or which members, if more than one) 

 is present in the several oils I have cited, I cannot inform you until I have 

 ascertained the composition of their respective alkaloids, a labour of so 

 tedious a kind, that I cannot promise to perform it for some time to come. 



Art. LXXIX. — On a Property possessed by Essential Oils of whitening the 

 Precipitate produced by ^nixing a Solution of Mercuro-iodide with one of 

 Mercuric-chloride. By William Skey, Analyst to the Geological Survey 

 of New Zealand. 



{Read before the Wellington Philosophical Society, llth August, 1878.] 



In article 83 of the last volume of our Transactions,* I showed that 

 solutions of certain alkaloids and albumeuoids, made so weak that they will 

 not give any precipitates with mercuro-iodide of potassium, will give them 

 immediately that a little mercuric-chloride is mixed therewith, in addition 



' * Trans. N.Z.I., IX., p. 553. ~~~~ 



