POPULAR SCIENCE REVIEW. 
resources of Australia. His reports are particularly cheering. They show 
that even in their oldest gold-fields, mining is yet in its infancy. Alluvial 
fields are still unexhausted, and auriferous quartz reefs without number 
lie untouched in every district for want of capital and labour. 
The correspondent also draws attention to mines of antimony, silver, 
and iron ; of which little or nothing was before popularly known. 
Gold in Wales . — During the past quarter, mining periodicals have been 
thickly strewn with reports, generally very sanguine, of the progress of gold 
mining in the principality ; with analyses of the quartz, and latterly with 
prospectuses of companies and their usual accompaniments. No further 
agitation is required to bring the subject under the notice of the mining or 
share-dealing public. 
Mr. Readwin, the pioneer of this enterprise, read a very interesting 
paper on the subject before the British Association, to which we refer our 
readers. 
METALLURGY. 
In these days of armour-plates and monster cannons, the manufacture 
of iron holds the first place in metallurgical interest. The magnitude 
with which iron smelting is conducted may be judged of by the following 
items, taken from Truran’s new work on the iron manufacture of Great 
Britain. At Dowlais, the weekly make of iron is about 130 tons, and the 
ordinary weekly amount of slag, 250 tons. The materials delivered weekly 
at the top of the furnaces would occupy 1,066 cubic yards. The un- 
delivered in the same time by the tuyeres (i.e. the nozzles of the blast 
apparatus) weighs 1,695 tons and measures 50,550,400 cubic feet. Each 
ton of iron is reduced by 43'5 cwt. of carbon, and 388,800 cubic feet, or 
13 tons of air. The weight of air is to the weight of material added at 
the top, as sixteen to seven. For each ton of liquid matter obtained (that is, 
including both iron and slag), no less than 129 cwt. of gases are evolved 
from the furnace. 
Puddling by Machinery .— In the conversion of cast-iron into malleable 
iron by the process of puddling, the most intense bodily labour is involved ; 
whilst the workmen are exposed to an overpowering heat. It is, there- 
fore, satisfactory to find that machinery has been introduced into the 
process — an invention having been patented by MM. Dumey and Lemut, 
of St. Dizier, France, through a London agent. 
Effect of Wolfram on Steel . — A series of experiments have been carried 
out by direction of the French minister of war, to ascertain the effect 
of the addition of wolfram to bronze, wrought-iron, and steel. The 
report states that there is no advantage to be got by adding it to bronze, 
and probably little in the case of wrought iron ; but that wolfram may 
safely be recommended to give to steel qualities which increase its value 
considerably. It concludes by saying that the small addition which would 
ensue in the price of the steel would be far more than counterbalanced by 
the advantages obtained. 
