Consolidated Copper Mines, situated in the parish of Gwennap, about
three miles from Redruth. They extend along the brow of a range of
steep hills, into which numerous shafts are sunk. The length of the
whole of these shafts together, it is calculated, is more than twelve
miles in perpendicular depth, and if to these are added the horizontal
galleries, which perforate the hill in all directions, the extent of
subterranean excavation is upwards of sixty miles.
Eight steam-engines of the largest size, and thirty of smaller
dimensions, are employed for drainage and other purposes, their ordinary
working power being equal to 4000 horses, but when their full power is
put on they almost equal that of 8000. To carry off the water from
these mines, a tunnel, with numerous ramifications has been formed,
measuring nearly thirty miles in length. One branch of this tunnel is
upwards of five miles long, carried underground 400 feet beneath the
surface, finding its outlet into the sea near Falmouth.
A few years ago the number of tin mines worked in Cornwall amounted to
139, and to 26 in Devonshire; and about 20,000 persons were employed in
them.
Although the wages of the miners are much inferior to those of the
pitmen in the northern coal-fields, yet they have advantages over their
brethren, being exempted from many of the evils to which the northern
miners are subjected. They have no fear of the fatal fire-damp or
sudden explosions. Intellectually they are also superior, as they are
mostly engaged in work requiring the exercise of mind. Their wages
arise from contract, and depend greatly upon their skill and energy.
They mostly have gardens, which they cultivate, and when near the coast
they engage in the fisheries, thus increasing their incomes and varying
their mode of life.
After leaving Redruth the travellers proceeded over the wildest and most
desolate of moorlands, with blocks of stone scattered about, towards the
wonderful Botallack Mine, on the Cornish coast. No mine in the world is
so singularly placed. Descending to the shore below, on looking
upwards, the view appeared fearfully grand. In one part was a powerful
steam-engine, which had to be lowered almost 200 feet down the cliffs.
Here tall chimneys, pouring out dense volumes of smoke, were seen
perched on the ledges of a tremendous precipice. Here and there also
were the huts of the miners, disputing the ground with the wild
sea-birds, while ladders of great length scaled the rocks in all
directions, enabling them to ascend and descend to their work. In some
parts were paths up which sure-footed mules, with riders on their backs,
were trotting briskly along, where few people unaccustomed to dizzy
heights would have wished to venture even on foot.
As they had determined to visit the mine, they had to ascend to the top
of the cliff and then once more to descend among the rugged rocks to a
ledge about midway between the summit and the ocean, where a small
building, occupied by the mining agent, marked the entrance. Hearing
who they were, the agent at once undertook to guide them, and produced a
couple of woollen mining dresses and two large felt hats.
Each person having fastened four or five candles to his button hole,
while he carried another in his hand, they began to descend through a
trap-like entrance, by a series of ladders, which although strong enough
in reality had a very rickety feeling. On reaching the foot of one
ladder, they were conducted to the top of another, on to which they had
to step, and thus descending ladder after ladder and passing ledge after
ledge, they at length reached the bottom of the pit, where the end of a
pump was seen drawing up the water from all parts of the mine.
They then commenced their progress along one of the numberless
galleries, which was so narrow that two persons could scarcely pass each
other. Now having to step over rough stones and often close to the
edges of fearful pits, now to bend low under masses of overhanging rock,
and sometimes to find themselves crossing unknown abysses by shaky
bridges of planks, while the damp air felt hot and sickly, making the
candles burn dimly. Here miners were at work with pickaxes getting out
the ore. Having thus gone over, through, and under all impediments,
they were informed that they were 120 feet below the level of the sea
vertically, and horizontally 480 feet below low-water mark. Boats might
even then be passing over their heads. Human beings were working still
lower down. On the roof, the strips of pure copper could be
distinguished among the crevices of the rocks through which the salt
water was seen percolating in an unpleasant abundance. In their
eagerness to obtain the rich ore, the miners had worked upwards until
they had got within five or six feet of the bottom of the ocean. There
the metal was still clearly visible, but even the most hardy miners
would scarcely have ventured on an attempt to win another grain from the
rock overhead, lest the water should rush in and overwhelm them, and
inundate the mine.
Passing into a gallery where no one was at work, the travellers listened
in perfect silence, and could hear the low murmur of the ocean rolling
above their heads.
"Oh, that is nothing now," said their guide. "When a storm is raging, I
have heard the sound of the pebbles, which some large wave has carried
outwards, bounding and rolling over the rocky bottom. On standing
beneath the base of the cliff, where not more than nine feet of rock
intervened between the sea and my head, the heavy roll of the large
boulders, the ceaseless grinding of the pebbles, the fierce thunder of
the billows with the crackling and boiling as they rebounded, produced
an uproar such as those who heard it can never forget."
For many years a blind man worked in the Botallack Mine, and supported a
large family by his labour. So complete was his recollection of every
turning and winding, that he became a guide to his fellow-labourers,
when by any accident their lights were extinguished. He being
afterwards cruelly discharged, engaged himself as an attendant to some
bricklayers. While thus employed, with a hod of mortar on his back, he
fell from a platform and was killed.
There are several other mines similarly situated to that of the
Botallack on the coast of Cornwall, where the works are carried far
under the ocean. Among them are the Wheal Edward, the Levant, the Wheal
Cock, and the Little Bounds. In the two latter, the miners have
actually followed the ore upwards until the sea itself has been reached,
but the openings formed were so small that they were able to exclude the
water, by plugging them with wood and cement.
On returning from the mine, the travellers, having doffed their miners'
dresses, inspected the outward machinery employed in crushing the ore on
the landing-place in the side of the cliff, and drawing it up the
precipitous tram, which leads to the summit, where it is stamped and
prepared for exportation. It is mostly carried to Swansea, which, in
consequence of the abundance of fuel in the neighbourhood, owing to its
nearness to the sea, to its canals and railroads, has, in the course of
half-a-century, from a mere fishing village become a town containing
fully 40,000 inhabitants.
The Cornish mines are not the only ones which run under the sea. On the
Irish and some parts of the English coasts there are several coal mines
which are worked beneath the ocean bed to a great distance.
Another remarkable mine, that of Huelwherry, existed for many years on
the Cornish coast. A rocky spot at about 120 fathoms from the beach was
left dry at low-water, on which small veins of tin ore were discovered
crossing each other in every direction. Although the surface was
covered for about ten months in the year, and had at spring-tides
nineteen feet of water over it, while a heavy surf often broke on the
shore, a poor miner, named Thomas Curtis, about a century ago determined
to attempt winning the ore. The work could only be carried on during
the short time the rock appeared above water. Three summers were spent
in sinking the pump-shaft, which had every tide to be emptied of water.
A frame of boards, raised to a sufficient height above the spring-tides,
and rendered water-tight by pitch and oakum, was placed above the mouth
of the shaft. Its sides were supported by stout props in an inclined
direction. At the top of this wooden construction, which was twenty
feet in height, a platform of boards was secured, on which a windlass
was placed. The water was now pumped out of the mine and the machinery
set to work; but the sea penetrated through the fissures of the rock,
and greatly added to the labour of the workmen, while during the winter
months, on account of the swell, it was impossible to convey the tin ore
to the beach. Notwithstanding all these difficulties, the persevering
projector was rewarded by obtaining many thousand pounds worth of tin.
At length, during a gale, an American vessel broke from her moorings,
and demolished the machinery by striking against the stage, when the
water rushing in filled the mine. An attempt has been made of late
years to again work the mine with improved machinery, but the venture
not proving profitable it has been abandoned.
The travellers also visited the curious Carclaze tin mine near the town
of Saint Austell. It is a prodigious hollow or basin, nearly thirty
fathoms in depth and a mile in circumference, and has the appearance of
a natural crater rather than a hollow made by human hands.
The sides are almost perpendicular, and a few footpaths alone lead down
amid the rocks to the bottom. In every direction are seen the hollows
made by the miners of ancient days, the white colour of the granite
veined with the darker metalliferous streaks, and the curious shape of
the rocks formed by the streams flowing down its sides, give it a
remarkably picturesque appearance.
The machinery used for crushing the rock is set in motion by these
streams. On every side the men, women, and children employed on the
works are seen moving about in all directions, like a busy colony of
ants. The ore is obtained without much difficulty.
A tunnel has been formed at the bottom of the mine through which the
waters flow after they have performed their task, which also carries
away the crushed granite, while the heavier metalliferous substances are
precipitated into the troughs. Neither engine-house nor chimneys such
as are seen in other mines are visible, while every detail of the work
is exposed to view--indeed, the huge basin has the appearance of a mine
completely turned inside out.
There are two methods of smelting tin. By the most common, the ore,
mixed with culm, is subjected to heat on the hearth of a reverberating
furnace, when ordinary coal is employed. By the other method, the ore
is fused in a blast furnace, when wood fuel or charcoal is used. The
tin when smelted runs off from the furnace into an open receiver, from
which it flows into a large vessel, where it is allowed to settle.
After the scoriae have been skimmed off, the upper and purer portion of
the mass is refined, and the lower part re-melted.
CHAPTER FIVE.
THE METALS FOUND IN MINES.
The chief object of the travellers was to inquire into the mode in which
mines in different countries are worked, the causes of accidents, and
the best method of preventing them. Their knowledge was superior to
that which most of our readers are likely to possess, and it will be
necessary, in order to understand their proceedings, to glance at the
mining districts of the world, and to describe some of the principal
mines among them.
No country possesses, within the same area, so large an amount of varied
mineral wealth as Great Britain. Besides the seventeen coal districts
of Great Britain, we find in Scotland numerous lead mines in the clay
slate mountains on the borders of Lanarkshire and Dumfriesshire. In the
north of England, with Alston Moor as the centre, along the borders of
Northumberland, Cumberland, Westmoreland, and Durham, are extensive
veins of lead. Cumberland, the north of Wales, and the Isle of Anglesey
produce copper ore, as also mines of lead and magnesia, with many other
metals,--zinc, arsenic, cobalt, and bismuth. Iron in large quantities
is found in South Wales, South Staffordshire, and in the Scottish
coal-fields, where the ironstone appears in abundance alternating with
layers of coal and other strata, and is generally won from the same pit
as that from which the coal is extracted.
Besides coal, Ireland contains mines of copper and lead, found in the
slate and limestone ranges, contiguous to the sea coast. Crossing from
thence to Spain, we arrive in a country rich in mines, though, owing to
its distracted state, for many years greatly neglected. Here lead is
found in large quantities in the mountain chains.
Quicksilver is abundant from extensive veins of cinnabar in the province
of Mancha. In Galicia tin has been produced from very early times.
Iron ore is very abundant, and silver mines, for many centuries
abandoned, are now again being reworked. Gold was at one period
discovered in large quantities, but is supposed to be almost exhausted.
The most important coal-field of France is round Etienne, near Lyons.
Mining operations are also carried on in Brittany and the Vosges.
Although possessing less mineral wealth than England, the French were
far in advance of us in regard to the management of their mines.
Germany possessed the chief school for scientific mining. Its principal
metalliferous sites are the Hartz Mountains, on the borders of Hanover
and Prussia, and the Erzgebirge or Ore Mountains, which separate Saxony
from Bohemia. They yield silver, copper, lead, iron, tin, and cobalt.
The most prolific sites of the precious metals in Europe are possessed
by Austria. The Styrian Alps furnish a vast amount of iron. The
province of Carniola supplies quicksilver. Hungary and Transylvania,
copper, lead, antimony, and iron. The most extensive works are found in
the neighbourhood of the town of Cremnitz and Schemnitz. The veins in
this region obtain the enormous dimensions of from 20 to 200 feet in
width. The extensive forests of oak, pine, and beech which clothe the
hills supply fuel for the numerous smelting works, while water,
carefully collected into reservoirs, moves the required machinery. The
whole of the drainage of the mines is collected in a receptacle 600 feet
below the surface, from whence it is conveyed under a lofty mountain
ridge by a magnificent gallery twelve miles in length.
Norway and Sweden possess extensive mines of iron and copper, as also
silver. The latter country furnishes the best iron in the world, and it
is much used in England for the manufacture of steel.
Passing eastward to Russia, we find the rich mines of the Ural
Mountains, which divide Europe from Asia, and then on to the Altai chain
on the southern frontier of Siberia, we meet with rich mines of gold and
silver, and other valuable metals. On the European side of the Ural
there is a deposit of copper sand-ore, extending over a district of 480
miles in length, by 280 in breadth. The mineral wealth of Asiatic
Russia is far greater. It consists of copper ores; iron cropping out at
the surface, gold and platinum. The Altai Mountains especially produce
silver, and some gold, with lead and copper ores. The silver mines of
this region were worked at a very early period, as is proved by the
discovery of an excavation a thousand feet in length, from which a stone
sphinx was dug up, corroborating a statement of Herodotus that the
Scythians possessed mines of gold and silver, which, according to his
account, were guarded by monsters and griffins. Baron Humboldt supposes
that he referred to the bones of elephants, and other gigantic animals,
discovered at the present day in the steppes between the Ural and Altai
chains.
Crossing the Atlantic to America, we find vast quantities of the
precious metals in the mountains of the Brazils and along the whole
range of the Andes. In the province of Minasgeraes, gold is obtained
from subterranean excavations, as also by washing the surface soil, when
diamonds are also found. Auriferous deposits exist in the deep valleys
among the mountains of Chili, and in Peru and Bolivia are immense veins
of silver ore. High up on the Andes are the mines of Pasco and Potosi;
while in the same region, quicksilver, copper, lead, tin, and other
metals have been discovered. The copper mines being nearest the sea,
are generally worked, the ore being sent to Swansea.
The lofty plateau of Mexico in North America has, from the first, been
celebrated for its rich silver mines, of which there have altogether
existed no less than three thousand, but the larger number of these have
long been unworked. The gold mines of California and of Australia are
too well known to require mention; but we must not forget the rock oil,
concealed for ages in the North American continent. Both the United
States and Canada now yield an abundant supply.
The number of metals discovered beneath the surface, including the
metallic basis of the earth and alkalies, amounts to forty-two, but
metals, commonly so-called, number only twenty-nine. These are
platinum, gold, tungsten, mercury, lead, palladium, silver, bismuth,
uranium, vanadium, copper, cadmium, cobalt, arsenic, nickel, iron,
molybdenum, tin, zinc, antimony, tellurium, manganese, tatiaum,
chromium, columbium, rhodium, iridium, osmium, cerium. Many of these,
however, are so rare, that as yet they are of no practical use. Gold
has been known from the earliest ages, and is found in scales, threads,
grains, and rolled masses, or nuggets, which latter have been discovered
in California and Australia weighing from twenty to thirty pounds, but
the largest of all met with was in Asia, on the southern side of the
Urals.
Large quantities of gold were discovered on a marshy plain which had
been thoroughly turned over, when it was resolved to take down the
buildings in which the gold was washed, and under the very corner of one
of them a lump was found, weighing no less than ninety-six and a-half
pounds troy, and valued at 4000 pounds. Gold has been found in
Scotland, and in the county of Wicklow, Ireland, where about 10,000
pounds worth was picked up in the bed of a river by the inhabitants,
before the Government became aware of its existence. Gold is so
malleable that a single grain can be beaten out to form a gold leaf
covering a surface of fifty-six square inches, and it is so ductile that
the same quantity may be drawn into a wire 500 feet in length. Silver
is found embedded in various rocks, where it occurs in veins, assuming
arborescent or thread-like forms, and occasionally appearing in large
masses. The largest mass found in Europe was brought from Kongsberg, in
Norway, weighing upwards of 560 pounds, but another, won from the mines
of Peru, was said to weigh 800 pounds. The celebrated mines of Potosi,
10,000 feet above the sea, were discovered in 1545 by an Indian who,
when chasing a deer, laid hold of a shrub to assist in his ascent; it
came up by the roots, to which he found attached a quantity of
glittering particles, which he at once knew to be silver. Veins of
silver have been discovered in England and Scotland, but generally mixed
with lead.
Iron, the most useful of all metals, is found in large quantities in
England, in many parts of Europe, and the United States. At one time
Sussex was full of iron mines, the furnaces being fed with charcoal,
until so extensive was the destruction of the woods and forests that the
Government interfered, and placed restrictions on the consumption of the
timber.
On the discovery of the present method of smelting with pit coal, the
works, which at one time numbered 140 in Sussex alone, were abandoned,
and hop-fields now cover the ground where furnaces once blazed.
Copper ranks next to iron in utility. In Cornwall there are upwards of
100 copper mines. It derives its name from the island of Cyprus, where
it was first obtained by the Greeks. It is employed pure for numerous
purposes, and is also mixed with other metals to form bell metal,
speculum metal, for optical purposes, and German silver.
Lead occurs in veins most plentifully in mountain limestone districts,
and usually contains some portion of silver. There are lead mines in
various parts of England, as well as in Spain, Saxony, and in Bohemia,
and some very rich lead mines have of late years been worked in the
United States.
Tin is found in Cornwall in larger quantities than in any other part of
the world. It is generally discovered in the alluvial soil of low
grounds, where it is known as stream tin, because it has been washed by
the agency of water from the rocks in which it was originally embedded
mixed with sand and gravel. Tin is also found in the island of Banca,
in the Indian Archipelago, in Bohemia and Saxony, Chili and Mexico.
Mercury is a rare metal. The richest mines are at Almaden, a small town
of La Mancha, in Spain. It is also found in Austria, China, and Peru,
and a few other places. It is sometimes found in globules, but it is
generally procured from one of its ores, cinnabar, a sulphate of the
metal, of a red colour, and indeed identical with the richly prepared
paint vermilion. A thousand workmen are employed in the Spanish mines,
above or under ground. It freezes at an exceedingly low temperature,
and was found solid during midwinter by the traveller Pallas. Of the
other metals, some used as medicines, or pigments, or to form alloys, we
have not time now to speak.
CHAPTER SIX.
SALT AND QUICKSILVER MINES.
The object of the travellers was not only to inspect coal mines, but to
view the wonders of the subterranean world. It is impossible to do more
than give a very brief account of the places they visited. They had
found their way to the Carpathian Mountains, in order to visit the salt
mines of Wieliczka, a small town to the south of Cracow. The valley in
which the mine is situated is fruitful and picturesque. Descending by a
staircase of thirty feet or so, through a bed of clay, they arrived at
the commencement of the level galleries, which branch off in all
directions. Overhead was a ceiling of solid salt, under foot a floor of
salt, and on either side grey walls of salt, sparkling here and there
with minute crystals. The guide led them on through a bewildering maze
of galleries. Now they entered a grand hall, now descended by
staircases to another series of vaulted chambers. On every side was
solid salt, except where stout piers of hewn timber had been built up to
support the roof, or wooden bridges had been thrown over some vast
chasm. As they descended, the air became dry and agreeable, and the
saline walls more pure and brilliant. One hall, 108 feet in length,
resembled a Grecian theatre, the places where the blocks had been taken
out in regular layers representing seats for the spectators. Here and
there were gangs of workmen, some labouring at the solid floor, others
trundling wheel-barrows full of cubes of salt.
Soon after entering, they reached the chapel of Saint Anthony, excavated
in the times of the Byzantines, supported by columns, with altar,
crucifix, and life-size statues of saints. They appeared, from being
coated with smoke, to be of black marble, but Mark, putting his tongue
to the nose of one of the saints, discovered it to be of salt. Many of
the saints, however, were disappearing before the damp, which enters in
that higher region from the upper world. The heads of some, and the
limbs of others had already fallen.