PROCEEDINGS OF SECTION B. 387 
favourable circumstances. For estimating large quantities of the 
salts, as in manufactories, &c., the method may possibly be 
applicable, but in the analysis of igneous rocks it certainly cannot 
be trusted. 
In the sanidine erystals mentioned, the soda proved to be in 
excess of the potash, a gravimetric determination giving potassium 
oxide 4:49 per cent., and sodium oxide 6°16 per cent. The results 
obtained by the volumetric method were—Potassium oxide 3°68 
per cent., and sodium oxide 6°77 per cent. ; but I have no hesita- 
tion in saying that this wide divergence is solely due to the 
unreliability of the latter test. 
The determination by platinum bichloride may be a little 
tedious, but there is always the great satisfaction of knowing that 
it gives almost absolutely accurate results. 
6.—AUSTRALIAN METEORITES. 
By A. Liversipce, M.A., F.R.S., Professor of Chemistry 
University of Sydney. 
| Abstract | 
THe Zhunda meteorite, found near Windorali in the Diamantina 
district, Queensland. The mass received by me originally weighed 
137 lbs., and the specific gravity is 7:78. In composition it consists 
essentially of nickeliferous iron, containing a trace of cobalt, 
together with a little sulphur, phosphorus and carbon. The 
erystalline structure is extremely well-marked, which is not only 
shown by the fractured surface, but by the cut and polished 
sections when etched by acids, bromine, or copper sulphate. 
This meteorite is also remarkable for the many nodules of 
sulphide of iron which it contains, from which fissures proceed 
in such a way as to show that the iron sulphide must have 
crystallised last ; in fact, it looks as if it had been the cause of 
the fissures. 
Barratta Meteorites, Nos. 2 and 3.—The first meteorite found 
at Barratta, near Deniliquin, in New South Wales, has already 
been described in the journal of the Royal Society of New South 
Wales for 1872 and 1880. 
These later ones, also in the possession of Mr. Russell, F.R.S., 
Government Astronomer, Sydney, were found near the site of 
the first ; the second one has a weight of 31 lbs. and a specific 
gravity of 3°706; the third weighs 48 lbs. and has a specific 
gravity of 3.429; the first having a specific gravity of 3:429. 
In structure and appearance all three are very much alike, and 
they consist essentially of silicates of magnesia (as enstatite), 
iron, with small quantities of other substances, intermingled with 
a network of nickeliferous iron. x2 
