1874.] Metallurgy. 539 
Loutit Bay, Apollo Bay, and the Wannon, have been examined, but the result 
is by no means encouraging. Mr. Mackenzie, the Government Examiner of 
Coal-Fields in New South Wales, has reported that—in spite of what may 
have been said to the contrary—no workable seam of coal has yet been 
opened up in any part of Victoria. The Board consequently does not feel 
justified in recommending the expenditure of more money in boring for coal. 
The most important fuel in the Colony appears to be the lignite of Lal-lal, 
where a deposit occurs not less than roo feet in thickness. This lignite has 
been described before the Geological Society of London, by Mr. R. Ethe- 
ridge, jun. 
But if Victoria is not blessed with coal, it has extraordinary treasures in its 
gold-fields. A Report on the Mineral Resources of Ballarat, by Mr. R. A. F. 
Murray, has been issued by the Geological Survey of Victoria. Not only is 
the geological structure of the country described, but the intricate system of 
auriferous ‘leads’? has been worked out with much care. The gold-bearing 
drifts, associated with volcanic rocks which have been erupted at different 
periods, are classified under four heads. In connedtion with these drifts it is 
interesting to study the distribution of the quartz-reefs. It may be regarded 
as established that the supply of alluvial gold was derived from veins disinte- 
grated during the various drift-periods, and that the gold—except in very fine 
particles—has not travelled far from the spot where it was separated from its 
parent-rock. In the distri@ around Ballarat the richest ground is always in 
the neighbourhood of the quartz-reefs. 
METALLURGY. 
At the recent meeting of the Royal Cornwall Polytechnic Society a good 
deal of interest was excited by Mr. King’s Patent Magnetic Ore Separator. 
This apparatus is used for the separation of minerals containing iron, in cases 
where the iron-ore is associated with other minerals. It is at present em- 
ployed at the Ballycorkish Mines, in the Isle of Man, where the ore consists 
of a mixture of galena, blende, and spathose iron-ore. The lead-ore may be 
readily separated by taking advantage of its high specific gravity; but the 
blende and spathic ore, being of nearly the same density, could not be properly 
separated by even the best systems of sizing and mechanical dressing. Hence 
the introduction of the Magnetic Separator. The stuff, after being crushed, 
is roasted at a dull red heat in revolving retorts, when the carbonate of iron 
is decomposed, and a magnetic oxide produced. The roasted ore is ther 
transferred to the hopper of the magnetic apparatus. This consists of a large 
drum or wheel, about 18 inches in diameter and ro inches in breadth, furnished 
within with a system of magnets arranged radially. The mixed ore, in its 
passage over a series of four of these drums, has its magnetic portion gra- 
dually separated by attraction, and the part which escapes the magnetic drum 
is clean blende. Mr. King proposes to apply his system to the separation of 
tin-ore from the iron-pyrites, copper-pyrites, and mispickel, with which it is 
frequently associated in our Cornish mines. Wher these mixed ores are 
roasted, the pyrites may be transformed into magnetic pyrites. 
“Our Tin Produdion and Tin Trade” formed the subje& of a valuable 
paper, by Mr. Robert Hunt, F.R.S., recently contributed to the Miners’ 
Association. According to the returns of the Board of Trade, the exports of 
tin of British production was 114,201 cwts. in 1871, 113,871 cwts. in 1872, and 
115,946 cwts. in 1873. Of tin of foreign and colonial production we exported 
41,196 cwts. in 1871, 48,634 cwts. in 1872, and 28,869 cwts. in 1873. Cornwall 
has now to compete not only with the tin production of “the Straits,’ in- 
cluding the Malacca Peninsula and the islands of Banca and Billiton, but 
also with the newly-discovered tin districts of Queensland, New South Wales, 
and Tasmania. 
Mr. Crampton’s revolving furnace for puddling iron was described by the 
inventor in a paper recently read before the Iron and Steel Institute. Small 
coal or slack is utilised as fuel, and is introduced with a current of air in such 
