704, REPORT— 1863. 
pyrites is shipped at Levanger. It contains 44 per cent. of sulphur, is easily 
broken, and does not flux in the kiln. The quantity of copper it contains 
being less than 1 per cent., the burnt residue cannot be profitably smelted 
for copper. 3. The most extensively used pyrites is shipped from Huelva, 
in Spain, and Pomeron, in Portugal. The mines are situated on each side 
of the boundary between the two countries. They were most extensively 
worked in ancient times, but their recent development has arisen from the 
use of the ore as a source of sulphur. Containing only from 2 to 4 per cent. 
of copper, it was unable to compete with the richer ores which, from time to 
time, became available in different parts of the world; but the mining is 
now rendered profitable in consequence of the sulphur haying acquired a 
value as well as the copper. The percentage of sulphur varies from 46 to 
50. The practical difficulty in burning this ore, namely, its great fusibility 
at the point where the combustion of the sulphur gives rise to considerable 
heat, has been overcome by the adoption of kilns, first used in Lancashire, in 
which the area of the surface is large in proportion to the weight of the 
charge of pyrites. The use of cupreous pyrites has led to the introduction of 
the manufacture of copper on the Tyne, which will this year amount to be- 
tween 700 and 800 tons. The ordinary process of smelting is employed ; but 
the moist method is also being tried, the advantage being, that by this 
method all the ingredients of the mineral are utilized, the oxide of iron 
making an ore of similar quality to hematite. The smelting process, how- 
ever, is still preferred in the large manufactories. In 1860, several cargoes 
of an ore containing free sulphur imbedded in gypsum were imported from 
the island of Milo, in the Archipelago. From the small quantity of sulphur 
contained in it (19 up to 24 per cent.), great difficulty was experienced in 
burning it, except in large masses. Subjoined is an analysis of one parcel 
of it :— 
Salonur se... ee emt te 24:00 
Oy peait Fes: Hee et 62°20 
SandiGicrss Ss SvOh et ee Lee 6:00 
Water! 2440. {Me GRe HP ee 7:00 
99-20 
Still more recently, Professor Ansted has discovered a deposit of free 
sulphur in Corfu, of which he has been kind enough to forward a sample; 
but we believe it has not been used in commerce. When sulphuric acid is 
wanted quite free from arsenic, Sicilian sulphur must be used. So largely 
has pyrites displaced sulphur in the production of sulphuric acid, that in 
1862 only 2030 tons of sulphur were consumed, against 72,800 tons of 
pyrites; and, reckoning the above quantity of sulphur as equivalent to 
4500 tons of pyrites, it appears that 77,300 tons of pyrites are annually used 
for the manufacture of sulphuric acid, along with 2500 tons of nitrate of 
soda. Assuming a produce of 120 per cent. on the pyrites, this is equal to a 
production of 92,760 tons of sulphuric acid, calculated as concentrated. This 
quantity of sulphuric acid is nearly all consumed where it is made, for the 
manufacture of other chemicals, such as soda and manures, the quantity sold 
being 6440 tons; but this might be more correctly described as consumed in 
other works, for the quantity sent to a distance is very small. Four-fifths 
of the sulphuric acid is used for the decomposition of common salt. 
Salt and the Alkali trade.—The ordinary Cheshire salt is almost ex- 
clusively used for the manufacture of alkali, the exception being in one 
