+---------+-------+----------+
| Years. | Ores. | Metal. |
+---------+-------+----------+
| |_Tons._| _Tons._ |
|1771-1781| 28,185| 3380 |
|1781-1791| 32,854| 4123 |
|1791-1801| 48,034| 4083 |
|1801-1811| 67,533| 6060 |
|1811-1816| 78,237| 7181 |
| 1816 | 83,058| 7045 |
| 1817 | 75,016| 6608 |
| 1818 | 80,525| 6714 |
| 1819 | 92,234| 7214 |
| 1820 | 92,672| 7364 |
| 1821 | 98,803| 8163 |
| 1822 |106,723| 9331 |
| 1826 |128,459| -- |
| 1827 | -- |12,381 |
| 1828 |153,600|12,169 |
| 1829 | -- |11,994 |
| 1830 | -- |13,097 |
| 1831 | -- |14,480 |
| 1832 | -- |14,463[18]|
+---------+-------+----------+
[18] Taylor’s Records of Mining, Part I., p. 171.
Quantity of Copper produced in the several districts of Great Britain
and Ireland:--
+----------------------+--------+--------+--------+--------+--------+
|With Ores from-- | 1828. | 1829. | 1830. | 1831. | 1832. |
+----------------------+--------+--------+--------+--------+--------+
| | _Tons._| _Tons._| _Tons._| _Tons._| _Tons._|
|Cornwall | 1966 | 9763 | 10,890 | 12,218 | 12,099 |
|Devonshire | 434 | 318 | 368 | 312 | 249 |
|Other parts of England| 71 | 36 | 10 | 31 | 42 |
|Island of Anglesea | 738 | 901 | 815 | 809 | 852 |
|Other parts of Wales | 259 | 172 | 237 | 123 | 237 |
|Ireland | 706 | 790 | 768 | 972 | 974 |
|Isle of Man | -- | 4 | 9 | 15 | 12 |
| | ------ | ------ | ------ | ------ | ------ |
|Total copper from the | 12,169 | 11,994 | 13,097 | 14,480 | 14,465 |
|ores of the United | | | | | |
|Kingdom | | | | | |
|Copper smelted from | -- | 30 | 124 | 100 | 56 |
|Foreign ores | | | | | |
| | ------ | ------ | ------ | ------ | ------ |
|General total | 12,169 | 12,024 | 13,221 | 14,580 | 14,521 |
+----------------------+--------+--------+--------+--------+--------+
_Statistics of Copper for Cornwall in 1837._--The total quantity of ore
sold was 142,089 tons (of 21 cwts.), yielding an average produce of
eight per cent.; the quantity of fine copper being 11,209 tons 1 cwt.;
and the average price of the ore 5_l._ 15_s._ 6_d._; the total amount of
the sales for the twelve months being 822,516_l._ The standard upon the
5th of January was 127_l._ 16_s._; this was the highest for the year.
Upon the 22d of June it was at the lowest, being only 93_l._ 18_s._ It
went up again to 120_l._ 10_s._ upon the 5th of October; but declined
with some slight fluctuation to 107_l._ 18_s._ upon the 28th of
December. The largest quantity sold at any one ticketing, was 4670 tons,
upon the 4th of May: and the smallest 1088, upon the 17th of August. The
highest produce was nine and five-eighths per cent. upon the 13th of
July; and the lowest, seven, upon the 26th of January. The greatest
weekly total was 25,887_l._, upon the 2nd of November, and the least
5694_l._ upon the 17th of August. The average sum per week was
15,817_l._[19]
[19] Mining Review, Feb. 28, 1838.
Table of the produce of Copper Ores and fine Metal in Cornwall, from
1800 to 1830.
+------+---------+----------+--------------+---------+-----------+
|Years.| Ores. | Metal. | Value of Ore.| Metal. | Average |
| | | | | | Standard. |
+------+---------+----------+--------------+---------+-----------+
| | | | | _Per_ | _Price_ |
| |_Tons of_|_Tons._ | | _Cent._ | _per Ton._|
| |_21 Cwts_| _Cwt._| _£ s. d._|_of Ore._| _£ s. d._|
| 1800 | 55,981 | 5187 0 |550,925 0 0 | 9-1/4 | 133 3 6 |
| 1801 | 56,611 | 5268 0 |476,313 0 0 | 9-1/4 | 117 8 0 |
| 1802 | 53,937 | 5228 15 |445,094 0 0 | 9-5/8 | 110 18 0 |
| 1804 | 64,637 | 5374 18 |507,840 11 0 | 8-3/8 | 136 5 0 |
| 1806 | 79,269 | 6863 10 |730,845 6 0 | 8-5/8 | 138 5 0 |
| 1808 | 67,867 | 6795 13 |495,303 10 0 | 10 | 100 7 0 |
| 1810 | 66,048 | 5682 19 |570,035 8 0 | 8-1/2 | 132 5 0 |
| 1812 | 71,547 | 6720 7 |549,665 6 0 | 9-3/8 | 111 0 0 |
| 1814 | 74,322 | 6369 13 |627,501 10 0 | 8-1/2 | 130 12 0 |
| 1816 | 77,334 | 6697 4 |447,959 17 0 | 8-5/8 | 98 13 0 |
| 1818 | 86,174 | 6849 7 |686,005 4 0 | 7-7/8 | 134 15 0 |
| 1820 | 91,473 | 7508 0 |602,441 12 0 | 8-1/8 | 113 15 0 |
| 1822 | 104,523 | 9140 8 |663,085 13 0 | 8-3/4 | 104 0 0 |
| 1824 | 99,700 | 7823 15 |587,178 0 0 | 7-7/8 | 110 0 0 |
| 1826 | 117,308 | 9026 12 |788,971 15 0 | 7-5/8 | 123 3 0 |
| 1828 | 130,366 | 9921 1 |756,174 16 0 | 7-5/8 | 112 7 0 |
| 1829 | 124,502 | 9656 10 |717,334 0 0 | 7-3/4 | 109 14 0 |
| 1830 | 143,296 |11,224 19 |887,900 0 0 | 7-3/4 | 114 4 0 |
| 1834 |}150,617 |12,271 14 |893,402 15 0 | 8-1/8 | 106 11 0 |
| 1835 |} | | | | |
+------+---------+----------+--------------+---------+-----------+
Produce of Copper Mines in Cornwall, (on the authority of John Taylor,
Esq. F.R.S.)
+------+-------+-------+--------------+----------+---------+
|Years.| Ore. |Metal. | Value. | Produce. |Standard.|
+------+-------+-------+--------------+----------+---------+
| |_Tons._|_Tons._| _£. s. d._|_Per Cwt._| |
| 1831 |144,402|12,044 |806,090 15 6 | 8-1/4 | 100 |
| 1832 |137,357|11,948 |825,612 6 0 | 8-5/8 | 100 |
| 1833 |138,300|11,191 |858,708 10 0 | 8-1/8 | 111 |
| 1834 |143,296|11,226 |887,902 0 0 | 7-3/4 | 114 |
| 1835 |150,617|12,270 |893,402 14 0 | 8-1/8 | 106 |
| 1836 |140,981|11,647 |957,752 8 6 | 8-1/4 | 115 |
| 1837 |140,753|10,832 |908,613 15 0 | 7-5/8 | 120 |
+------+-------+-------+--------------+----------+---------+
An account of the quantities of Foreign wrought and unwrought Copper,
and Copper Ore imported and exported, and of British wrought and
unwrought Copper exported from the United Kingdom; together with the
quantities and value of Copper Ore smelted in Cornwall and Swansea, and
the quantity of Copper produced in those places; and in the county of
Devon; together with the market prices of sheet and cake Copper, in the
year ending 5th January, 1835.
+---------------------------------------------+-------+--------------+
| |Quanti-| Value. |
| | ty. | |
+---------------------------------------------+-------+--------------+
|Foreign Copper imported:-- | | _£ s. d._|
| Unwrought in bricks or pigs, rose and cast | | |
| copper _Cwts._ | 5,389| |
| Part wrought, viz., bars, rods, or ingots, | | |
| hammered or raised | 1,968| |
| Wrought plates and coin | 2| |
| -- old for re-manufacture | 493| |
| Copper ore Foreign |278,900| |
| Manufactures of copper, entered by weight | 650| |
| -- entered at value | -- | 5,353 0 0 |
|Foreign Copper exported, viz.:-- | | |
| Unwrought, in bricks and pigs, rose and | | |
| cast copper _Cwts._ | 6,898| |
| Part wrought, viz., bars, rods, or ingots, | | |
| hammered or raised | 2,013| |
| Old, fit only for re-manufacture | 265| |
| Smelted in the United Kingdom from foreign | | |
| ore | 55,456| |
| Manufactures of copper, entered by weight | 650| |
| -- entered at value | -- | 112 0 0 |
| | | |
| BRITISH COPPER. | | |
|Exported, unwrought, in bricks and pigs | | |
| _Cwts._ | 63,252| |
| -- wrought sheets, nails, &c. |103,433| |
| -- wire | 56| |
| -- of other sorts | 15,197| |
| -- Total of British copper exported |182,225| |
|Ores sold in Cornwall:-- | | |
| Quantity of ore _Tons_ |150,617| |
| Value of ditto | -- |893,403 0 0 |
| Quantity of metal _Tons_ | 12,270| |
| Standard | -- | 106 11 0 |
| Produce per cent. | 8-1/2| |
|Ores sold, &c. in Swansea:-- | | |
| Quantity of ore _Tons_ | 28,746| |
| Value of ditto | -- |223,958 0 0 |
| Quantity of metal _Tons_ | 2,832| |
| Standard | -- | 101 18 0 |
| Produce per cent. | 9-7/8| |
|Copper sold in Devonshire { ore } _Tons_ |{ 5,114| |
| { metal } |{ 455| |
|Total quantity of copper raised in the } | | |
|United Kingdom, exclusive of Anglesea and } | | |
|Staffordshire, and deducting 1083 tons of } | | |
|metal, value 88,207_l._, the produce of } | | |
|4985 tons of foreign ore sold at Swansea, } |-------| |
|included above. } | 14,474| |
+---------------------------------------------+-------+--------------+
COPPERAS. (_Couperose verte_, Fr.; _Eisenvitriol_, Germ.) Sulphate of
iron.
CORAL, (_Corail_, Fr.; _Koralle_, Germ.) is a calcareous substance,
formed by a species of sea polypus, which constructs in concert immense
ramified habitations, consisting of an assemblage of small cells, each
the abode of an animal. The coral is therefore a real polypary, which
resembles a tree stripped of its leaves. It has no roots, but a foot not
unlike a hemispherical skull-cap, which applies closely to every point
of the surface upon which it stands, and is therefore difficult to
detach. It merely serves as a basis or support to the coral, but
contributes in no manner to its growth, like the root of an ordinary
tree; for detached pieces have been often found at the bottom of the sea
in a state of increase and reproduction. From the above base a stem
usually single proceeds, which seldom surpasses an inch in diameter, and
from it a small number of branches ramify in very irregular directions,
which are studded over with cells, each containing an insect. The
polypi, when they extend their arms, feelers, or _tentacula_, resemble
flowers, whence, as well as from the form of the coral, they were
classed among vegetable productions. They are now styled zoophytes by
the writers upon Natural History.
The finest coral is found in the Mediterranean. It is fished for upon
the coasts of Provence, and constitutes a considerable branch of trade
at Marseilles. The coral is attached to the submarine rocks, as a tree
is by its roots, but the branches, instead of growing upwards, shoot
downwards towards the bottom of the sea; a conformation favourable to
breaking them off and bringing them up. For this kind of fishing, eight
men, who are excellent divers, equip a felucca or small boat, called
commonly a coralline. They carry with them a large wooden cross, with
strong, equal, and long arms, each bearing a stout bag-net. They attach
a strong rope to the middle of the cross, and let it down horizontally
into the sea, having loaded its centre with a weight sufficient to sink
it. The diver follows the cross, pushes one arm of it after another into
the hollows of the rocks, so as to entangle the coral in the nets. Then
his comrades in the boat pull up the cross and its accompaniments.
Coral fishing is nearly as dangerous as pearl fishing, on account of the
number of sharks which frequent the seas where it is carried on. One
would think the diving-bell in its now very practicable state might be
employed with great advantage for both purposes.
Coral is mostly of a fine red colour, but occasionally it is
flesh-coloured, yellow, or white. The red is preferred for making
necklaces, crosses, and other female ornaments. It is worked up like
precious stones. See LAPIDARY.
CORK, (_Liége_, Fr.; _Kork_, Germ.) is the bark of the _quercus liber_,
Linn., a species of oak-tree, which grows abundantly in the southern
provinces of France, Italy, and Spain. The bark is taken off by making
coronal incisions above and below the portions to be removed; vertical
incisions are then made from one of these circles to another, whereby
the bark may be easily detached. It is steeped in water to soften it, in
order to be flattened by pressure under heavy stones, and next dried at
a fire which blackens its surface. The cakes are bound up in bales and
sent into the market.
There are two sorts of cork, the white and the black; the former grows
in France and the latter in Spain. The cakes of the white are usually
more beautiful, more smooth, lighter, freer from knots and cracks, of a
finer grain, of a yellowish gray colour on both sides, and cut more
smoothly than the black. When this cork is burned in close vessels it
forms the pigment called _Spanish black_.
This substance is employed to fabricate not only bottle corks, but small
architectural and geognostic models, which are very convenient from
their lightness and solidity.
The cork-cutters divide the boards of cork first into narrow fillets,
which they afterwards subdivide into short parallelopipeds, and then
round these into the proper conical or cylindrical shape. The bench
before which they work is a square table, where 4 workmen are seated,
one at every side, the table being furnished with a ledge to prevent the
corks from falling over. The cork-cutter’s knife is a broad blade, very
thin, and fine edged. It is whetted from time to time upon a
fine-grained dry whetstone. The workman ought not to draw his knife edge
over the cork, for he would thus make misses, and might cut himself, but
rather the cork over the knife edge. He should seize the knife with his
left hand, rest the back of it upon the edge of the table; into one of
the notches made to prevent it from slipping, and merely turns its edge
sometimes upright and sometimes to one side. Then holding the squared
piece of cork by its two ends, between his finger and his thumb, he
presents it in the direction of its length to the edge; the cork is now
smoothly cut into a rounded form by being dexterously turned in the
hand. He next cuts off the two ends, when the cork is finished and
thrown into the proper basket alongside, to be afterwards sorted by
women or boys.
Of late years a much thicker kind of cork boards have been imported from
Catalonia, from which longer and better corks may be made. In the art of
cork-cutting the French surpass the English, as any one may convince
himself by comparing the corks of their champagne bottles with those
made in this country.
Cork, on account of its buoyancy in water, is extensively employed for
making floats to fishermen’s nets, and in the construction of
life-boats. Its impermeability to water has led to its employment for
inner soles to shoes.
When cork is rasped into powder, and subjected to chemical solvents,
such as alcohol, &c., it leaves 70 per cent. of an insoluble substance,
called _suberine_. When it is treated with nitric acid, it yields the
following remarkable products:--White fibrous matter 0·18, resin 14·72,
oxalic acid 16·00, suberic acid (peculiar acid of cork) 14·4 in 100
parts.
_Machine cork-cutting._--A patent was obtained some years ago by Sarah
Thomson for this purpose. The cutting of the cork into slips is effected
by fixing it upon the sliding bed of an engine, and bringing it, by a
progressive motion, under the action of a circular knife, by which it is
cut into slips of equal widths. The nature or construction of a machine
to be used for this purpose may be easily conceived, as it possesses no
new mechanical feature, except in its application to cutting cork. The
motion communicated to the knife by hand, steam, horse, or other power,
moves at the same time the bed also, which carries the cork to be cut.
The second part of the invention, viz. that for separating the cork into
square pieces, after it has been cut in slips as above, is effected by a
moving bed as before, upon which the slips are to be placed and
submitted to the action of a cutting lever, which may be regulated to
chop the cork into pieces of any given length.
The third part of the invention, viz., that for rounding or finishing
the corks, consists of an engine to which is attached a circular knife
that turns vertically, and a carriage or frame upon its side that
revolves upon an axle horizontally.
This carriage or frame contains several pairs of clamps, intended
respectively to hold a piece of the square cut cork by pressing it at
the ends, and carrying it lengthways perpendicularly; which clamps are
contrived to have a spindle motion, by means of a pinion at the lower
end of their axles, working into a spur-wheel.
The machinery, thus arranged, is put in motion by means of bands and
drum-wheels, or any other contrivance which may be found most eligible;
and at the same time that the circular knife revolves vertically, the
frame containing the clamps with the pieces of cork, turns horizontally,
bringing the corks, one by one, up to the edge of the knife, when, to
render each piece of cork cylindrical, the clamps, as above described,
revolve upon their axes, independently of their carriage, by which means
the whole circumference of the cork is brought under the action of the
knife, the superfluous parts are uniformly pared off, and the cork
finished smooth and cylindrical.
CORROSIVE SUBLIMATE; bichloride of mercury.
CORUNDUM; or _Telesie_; a very hard genus of aluminous minerals, to
which the gems, sapphire, ruby, salamstein, and adamantine spar belong.
COTTON DYEING. (_Teinture de Coton_, Fr.; _Baumwollenfärberei_, Germ.)
Cotton and linen yarns and cloths have nearly the same affinity for
dyes, and may therefore with propriety be treated, in this respect,
together. After they have acquired the proper degree of whiteness (see
BLEACHING) they are still unfit to receive and retain the dyes in a
permanent manner. It is necessary, before dipping them into the
dye-bath, to give them a tendency to condense the colouring particles
within their cavities or pores, and to communicate such chemical
properties as will fix these particles so that they will not separate,
to whatever ordinary trial they may be subjected. All the colours which
it would be desirable to transfer to these stuffs unfortunately do not
possess this permanence. Men of science engaged in this important art
have constantly aimed at the discovery of some new processes which may
transfer into the class of fast colours those dyes which are at present
more or less fugitive. Almost all the goods manufactured of cotton,
flax, or hemp, are intended to be washed, and ought, therefore, to be so
dyed as to resist the alkaline and soapy solutions commonly used in the
laundry. Vitalis distinguished dyed cottons into three classes; 1. the
_fugitive_, or fancy-coloured (_petit teint_), which change their hue or
are destroyed by one or two boils with soap; 2. those which resist five
or six careful washings with soap, are _good_ dyes, (_bon teint_); and
those which were still more durable, such as Turkey reds, may be called
_fast_ colours (_grand teint_). The colours of Brazil wood, logwood,
annotto, safflower, &c., are _fugitive_; those made with madder without
an oily base, are _good_; and those of madder with an oily mordant, are
_fast_. It is, however, possible to point out certain processes for
giving these different orders of dyes a greater degree of fixity.
I shall describe, in the five following paragraphs, the operations
conducive to the fixation of colours upon cotton and linen.
1. _Galling._ Either gall nuts alone, or sumach alone, or these two
substances united, are employed to give to cotton the fast dye
preparation. 2 or 3 ounces of galls for every pound of cotton, being
coarsely pounded, are to be put into a copper containing about 30
gallons of water for every 100 pounds of cotton, and the bath is to be
boiled till the bits of galls feel pasty between the fingers. The fire
being withdrawn, when the bath becomes moderately cool, it is passed
through a hair-cloth sieve. If during this operation the liquor should
become cold, it must be made once more as hot as the hand can bear. A
portion of it is now transferred into another vessel, called a _back_,
in which the cotton is worked till it be well penetrated with the
decoction. It is then taken out, wrung at the peg or squeezed in a
press, and straightway hung up in the drying house. Some more of the
fresh decoction being added to the partially exhausted liquor in the
back, the process is resumed upon fresh goods.
The manipulation is the same with sumach, but the bath is somewhat
differently made; because the quantity of sumach must be double that of
galls, and must be merely infused in very hot water, without boiling.
When galls and sumach are both prescribed, their baths should be
separately made and mixed together.
2. _Aluming._ Alum is a salt which serves to prepare cotton for
receiving an indefinite variety of dyes. Its bath is made as follows:
For 100 pounds of scoured cotton, about 30 gallons of water being put
into the copper, are heated to about 122° F., when 4 ounces of alum,
coarsely pounded, are thrown in for every pound of cotton, and instantly
dissolved. Whenever the heat of the bath has fallen to about 98° F., the
cotton is well worked in it, in order that the solution may thoroughly
penetrate all its pores. It is then taken out, wrung at the peg or
squeezed in the press, and dried in the shade. The solution of alum is
of such constant employment in this kind of dyeing, that it should be
made in large quantities at a time, kept in the alum tun, where it can
suffer no deterioration, and drawn off by a spigot or stop-cock as
wanted.
There are certain colours which require alum to be deprived of a portion
of its acid excess, as a supersalt; which may be done by putting 1 ounce
of crystals of soda into the tun for every pound of alum. But so much
soda should never be used as to cause any permanent precipitation of
alumina. When thus prepared, it is called _saturated alum_, though it is
by no means neutral to litmus paper; but it crystallizes differently
from ordinary alum.
Cotton does not take up at the first aluming a sufficient quantity of
alum; but it must receive a second, or even a third immersion. In every
case the stuff should be thoroughly dried, with an interval of one or
two days between each application; and it may even be left for 10 or 12
hours moist with the alum bath before being hung in the air. When the
cotton is finally dry, it must be washed before being plunged into the
dye bath; otherwise, the portion of alum, not intimately combined with
the cotton, but adhering externally to its filaments, would come off by
the heat, mix with the bath, alter the colour by dissolving in it, and
throw it down to the bottom of the copper, in the form of a lake, to the
great loss of the dyer. Madder reds, weld yellows, and some other
colours, are more brilliant and faster when acetate of alumina, prepared
with acetate of lead, alum, and a little potash, is used, than even
saturated alum. This mordant is employed cold, and at 4° Baumé.