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FORTIA’S TRAVELS IN SWEDEN. 465
its fulphur, forming a fort of ore or richer pyrites of copper, purged from all {tony
matter, and called in Swedifh /ier/tein, which matter contains from ten to fifteen pounds
of copper per quintal, in lieu of two, which was the proportion in the rough ftate. This
Jrierftein or concentrated and purified ore, which is let out from the furnace by means of
a hole in the fide, as foon and as often as the crucible is full, is afterwards roalted four
or five times, in order that all the remaining fulphur may be fublimed. On the fecond
fufion which follows this fecond roafting, ali the remaining iron is converted into /oria,
fo that copper alone remains at the bottom of the crucible, yet mixed with from 8 to 12
per cent. in the whole, of iron, zinc, lead, arfenic, &c. all of which are afterwards fe-
parated at the refinery at Afveftad. ‘The fecond roafting, which requires four or five
fires, takes place in a houfe fheltered from the inclemency of the weather, requiring
much more care and attention in managing the fire than the former. The furnaces
employed for founding are from ten to fourteen feet higher than the crucible; thofe for
roafting are kilns, fomewhat refembling thofe ufed for lime in France, walled in on
three fides and open at the other. Ifinftead of two roaftings and fuffons the fame re-
fult were fought to be effected by one procefs, there would be a rifk of lofing too much
copper in the fcories, of having the copper extra€ted too much combined with iron,
and other heterogeneous matter, and confequently of a much greater lofs at the refinery ;
for in all chemical preparations when there is a great difproportion in the matters re-
quired to be feparated, (as here between the iron and the copper, the one containing
two per cent. of the one and fifty of the other) the extract of neither can be had exaétly
pure or free from heterogeneous mixture bya fingle procefs, fo long as fuch a difpro-
portion exifts. Thefe different roaftings and fufions for converting the ore into copper
take up altogether about fix months.
To be qualified for a founder a man mutt abfolutely be a proprietor, the holder of a
certain portion of land, and poffefs a fhare in a foundry. ‘The founders undergo ex-
amination before certain numbers of the council of the mines, nominated for the pur-
pofe. Their profits are no more than one rix-dollar per {chippund, and fometimes even
they are lofers; formerly, but this happened very rarely, they gained from five to fix
rix-dollars; all however depends on the price which is paid for the ore at public auc-
tion ; commonly of late years thirty tons of ore have produced a {chippund of copper ;
rarely has it happened that twenty-fix or twenty-eight tons have yielded that quantity.
The expence of founding is generally half a dollar per ton as an average price; each
founder commonly produces from 200 to 300 {chippunds annually. The ton of ore
is 6,3, cubic feet of Sweden; the ton of charcoal at Fahlun is 5 ,°, cubic feet, but in
every other part of Sweden it is the fame as aton of ore. Eighteen tons of charcoal is
one horfe’s draught, and cofts commonly from 32 to 36 and 40 {chillings. In 1790, the
price was 56 {chillings, and in 1791, 48, on account of the mildnefs of the winter, and
the fhort duration of the /ledge feafon. The crown furnifhes nearly 30,000 ftig, at a
certain price, viz. 8000 at 20 {chillings, and the refidue at 18. This fupply is brought
in by the peafantry of the eight neareft parifhes, as a commutation for territorial con-
tribution, and the capitation tax. The whole confumption is about 70,000 /tig, which
the peafantry are paid for in the following manner :-—
The ore from the mine is divided into fixteen lots, one of thefe lots is affefled bya
comptroller, and ferves as an eftimate for the reft, which are drawn for by lot (five af
the fifteen ferve to pay expences); this diftribution takes place four times a week. T he
crown was wont to receive the fourth {chippund until 17 70, it now receives no more than
the eighth.
VOL. VI. 30 The
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