BOOK of iron. The richeft part of the ore may perhaps yield 20 per
v. 1 cent. of copper ; but as the poor and the rich parts are blended,
they give only 2 per cent, when firfl: brought from the mine,
and 12 per cent, when once fmelted.
Large quantities of copper are alfo annually obtained, by
placing numerous pieces of iron into troughs of water, impregnated
with blue vitriol, by a procefs extremely fimple and very
common in chymical experiments, but which has led ignorant
perfons to believe, that the iron is changed into copper. The
Water having a greater affinity with iron than with copper dif-
folves the iron particles, and lets drop a proportionate number of
particles of copper before held in folution, which affiime the
places of the particles of iron recently dilfolved ; and as this operation
is continual and gradual, the pieces of iron in time are lo
entirely covered with the particles of copper as to appear to have
been converted into that metal.
T welve hundred workmen are employed ; namely, fix hundred
miners, and the fame number in roaiting and finelting the ore,
jn making charcoal, and other works above ground.
The morning after our arrival at Fahlun, we vifited the mine,
and defcended as far as we could penetrate. The mouth or opening
is extremely large, perhaps the largelt in the world, being
1200 feet in diameter, or near three quarters of an Englifh mile
in circumference: an immenfe chafm, - gradually enlarged to its
preflent fize by the excavations and frequent downfalls of the
rock.
We
We defcended this chafm by feveral flights of wooden Heps, CHAP.
till we arrived at the entrance of the firfl: fubterraneous gallery; ,
from whence the defcent is extremely commodious, not by ladders,
as is ufual in mines, but down Heps cut in the rock, and
Hoping fo gently as to be praiticable for the horfes employed in
bringing up the ore.
I will not defcribe the miners naked from their waifl: upwards,
and compare them, as they are carrying in their hands fmall bundles
of lighted flips of wood, to the Cyclops; nor will I dwell on
the fublimity of thofe tremendous founds formed by the explofion
of the gunpowder, circumftances common to all mines, and not
peculiar to this of Fahlun.
The galleries along which we pafled are from fix to ten feet
high, and fufficiently fpacious. The perpendicular depth of the
mine from the top of the chafm is 1020 feet, and 720 from the
entrance into the fubterraneous gallery to the bottom. The commodious
ftair-cafe continued till we came to a deep pit, to
which we defcended by means of a wooden ladder, and afterwards
by an iron ladder loofely fufpended along the fides of
the rock: flopping from thence to a wooden ladder, we reached
the loweil part to which we could then arrive, as the
loweft pit was full of water.
Our afcent, from its length, was long and tedious, and we
employed near four hours before we again iflued into day.
The country from Fahlun to Gefle, through the provinces of
V ol. III. D d Dalecarlia