“I remained three-quarters of an hour in these frightful and gloomy caverns, which find employment for not less than thirteen hundred workmen, and traversed every part of them which was accessible, conducted by my guides. The weather above was very warm, but here the ice covered the whole surface of the ground, and I found myself surrounded with the colds of the most rigorous winter, amid darkness and caves of iron. In one of these, which ran a considerable way beneath the rock, were eight wretched beings warming themselves round a charcoal fire, and eating the little scanty subsistence arising from their miserable occupation. They rose with surprise at seeing so unexpected a guest among them, and I was not a little pleased to dry my feet, which were wet with treading on the melted ice, at their fire.
“Having gratified my curiosity with a view of these subterraneous apartments, I made the signal for being drawn up, and felt so little terror while reascending, compared with that of being let down, that I am convinced, after five or six repetitions, I should have been perfectly indifferent to the undertaking. So strong is the effect of custom on the human mind, and so contemptible does danger or horror become when familiarized by repeated trials!”
Throughout the whole extent of Sweden, the iron mines at present wrought, employ thousands of persons, and yield annually upward of one hundred thousand tuns of metal. There are said to be between five and six hundred mines in the entire country, nearly half of which are situated in the central provinces: this, however, includes mines of all descriptions, though by far the most are of iron. The products of all these mines would be vastly greater than they are, were it not for the multiplied and unreasonable restrictions of the government.
The iron trade of the United States, and the domestic manufacture of iron, were spoken of by Mr. Gallatin, in a report to Congress, in 1810, as being firmly established. He was able to obtain very imperfect information about it, but it was known that iron ore was plentiful; that numerous forges and furnaces had been erected, supplying “a sufficient quantity of hollow-ware, and of castings of every description.” From Russia, about forty-five hundred tuns of bar iron were imported yearly, and perhaps another forty-five hundred from Sweden and England. A vague estimate gave fifty thousand tuns of bar iron as the annual consumption of the union, of which he considered forty thousand as the product of the republic. Some good iron was made in Virginia and Pennsylvania, but much inferior iron, carelessly manufactured,was brought into market. Of sheet, slit, and hoop iron, about five hundred and sixty-five tuns were annually imported; about seven thousand tuns were rolled and slit in the United States. Massachusetts had thirteen rolling and slitting mills, and the value of cut nails and brads made within the republic in a year, was estimated at twelve hundred thousand dollars. Nearly three hundred tuns of cut nails were exported. Agricultural implements were made at home, and much coarse ironmongery; but cutlery, fine hardware, and steel work, were brought from Britain. About forty thousand muskets were yearly made in New England and at Harper’s Ferry: also balls, shells, and brass and iron cannon, in various places. There were several iron founderies for machinery castings, and steam-engines had begun to be made at Philadelphia. Mr. Gallatin valued the iron and manufactures of iron then annually made at home, at from twelve to fifteen millions of dollars, and the imports at near four millions, as prices went.
Adam Seybert enumerates the domestic products of 1810, at 53,908 tuns of pig iron, from 153 furnaces; 24,541 tuns of bar iron from 330 forges; 15,727,914 pounds of nails (partly out of imported iron) from 410 naileries; and 6,500 tuns of iron were required at 316 trip-hammers and thirty-four rolling and slitting mills. His estimate of the value of the home manufacture is $14,364,526. In 1806 or 1807, Chancellor Livingston, then our minister to France, had to apply repeatedly to the British ministry for permission to buy in England, and export to New York, the steam-engine which Fulton put on board his first steamboat on the Hudson. Now, the manufacture of steam-engines is an important branch of our home industry.
In 1827-8, it was given in evidence before a committee of Congress, that Pennsylvania had made, during the past year, 21,800 tuns of bar iron, and 47,075 tuns of cast iron; that 3,000 tuns of bar iron were made near Lake Champlain; that three counties in New Jersey had made 2,050 tuns, and that in a circle of thirty miles’ diameter, in New York, there were one hundred and ten forge fires, each of them able to produce twenty-five to thirty-five tuns yearly. In 1830, a committee of Congress reported on the iron trade, and from their report and other later sources, we learn that that year 112,866 tuns of bar, and 191,537 of pig iron, worth $13,327,760, employing 29,254 men, who received $8,776,420 in wages, were made. Perhaps the quantity and number of workmen are overstated. In 1840, with improved machinery, only 30,497 men produced 484,136 tuns.
Without coal and iron, the United States and Britain never could have risen to the rank of first-rate powers. In fact, without iron, civilization must have made very slow progress, as must be evident to any one who willtake the trouble to try seriously to enumerate the various articlesessentialto society, of which iron is an indispensable part.
In 1839-40, according to the official returns, which are imperfect, the United States produced, with 804 furnaces, 286,903 tuns of cast iron, and with 795 blomaries, forges and rolling-mills, 187,233 tuns of bar iron. The capital invested was nearly twenty and a half millions of dollars; the men employed, miners included, were 30,497, and 1,528,110 tuns of fuel were employed in these operations. The value of iron and steel, and their manufactures, imported in 1839-40, as per official returns, was $7,241,407. The estimated value of the iron made in the United States that year, was $22,778,635; of which sum $15,585,730 were for labor, including mining, transportation, coaling, hauling, &c. The persons employed in the iron manufacture, and their families, were estimated at 213,505, which, at twelve and a half cents each, per day, for agricultural products consumed, would give $9,741,166.
In 1845, the product of the union was estimated thus: 540 blast furnaces, yielding 486,000 tuns of pig iron; 954 blomaries, forges, rolling-mills, &c. yielding 291,600 tuns of bar, hoop, sheet, boiler, and other wrought iron, 30,000 tuns of blooms and 121,500 tuns of castings; value of the whole nearly forty-two millions of dollars.
The United States imported of iron, chiefly bar and bolt, rolled, hammered, or otherwise manufactured, and pig, hoop and sheet, in 1838-9, 115,637 tuns; in 1839-40, 72,769; 1840-1, 112,111; in 1841-2, 107,392; in 1842-3, 38,405.
In 1846-7, we find by the treasury report, that the United States exported of domestic manufactures, 3,197,135 pounds of nails, worth $168,817, of which Cuba took 2,317,550 pounds; also other articles of iron and steel to the value of $998,667, of which $478,681 to Cuba, and $162,020 to British North America. In that year, among the imports, chiefly from England, were 549 tuns of steel, value $1,126,458; 55,599 tuns of bar iron; 28,083 tuns of pig; 1,893 tuns of scraps; 6,167,720 pounds of chain cables; 13,410,556 pounds of sheet and hoop; 1,412,332 pounds of anvils; 921,845 pounds of nails; 361,423 pounds of anchors; 975,256 pounds of castings; 170,909 pounds of cast-iron butts; 431,916 pounds of band; 660,133 pounds of round or square; 347,737 pounds of nail or spike rods.
Official tables show that the imports of manufactures of steel and iron in 1839, were worth $6,507,510; in 1843, $1,012,086; in 1844, $3,313,796; in 1845, $5,077,788; and that in 1839, the value of pig and bar iron and steel imported was $6,302,539; in 1842 and 1845, nearly four millions each year; in 1843, $1,091,598; and in 1844, $2,380,027.
Some idea of the extent of the iron trade inland may be formed from the quantities carried on the canals. In 1847, there came to the Hudson on the New York canals, pig iron, 21,608,000 pounds; bloom and bar 26,348,000 pounds; iron ware, 3,014,000 pounds: 340 tuns of iron and iron ware were cleared on the canals at Buffalo and Oswego; St. Lawrence county, N. Y., shipped 515 tuns of pig, a surplus made there; 7,716 tuns of pig iron reached BuffaloviaLake Erie, and 1,256 kegs of nails; 15,103,565 pounds of iron and nails arrived at Clevelandviathe Ohio canal, and 4,085 tuns of iron and 12,537 kegs of nails were shipped from Cleveland coastwise. There were cleared at Portsmouth, Chilicothe, Massillon, and Akron, in 1847, about 5,713 tuns of iron; 5,269,055 pounds of nails were shipped at Akron. The trade in coal and iron on the western rivers and lakes is very large.
Iron canal-boats were in common use in Wales thirty years ago: they are beginning to be made here; also war-steamers. Fences, and even porches to houses, are often of iron. The pipes for the Croton water in New York required many thousand tuns. The annual value of 150,000 tuns of iron ore of Maryland is worth $600,000 at Baltimore. A single foundery in Tennessee sold, in 1844, of sugar-kettles, $50,000 worth.
Child’s statistics show that in Pennsylvania, in 1847, there were made, at 213 furnaces, 98,395 tuns of cast iron, and at 169 blomaries, forges, &c., 87,244 tuns of bar iron, 11,522 men being employed, including limestone miners, and a capital of $7,751,470 invested. In 1846, there were 173,369 tuns manufactured, seven of the furnaces using anthracite coal. Forty furnaces, in 1847, were in blast, using anthracite, and producing 121,800 tuns of iron, at a reduced price, which price had induced capitalists to put up extensive rolling-mills. The American Quarterly Register has a list of nineteen anthracite rolling-mills in Pennsylvania, which make iron rails and plate, bar and rod, nails, axle and small iron.
The first bar of railroad iron ever manufactured in the United States, was made in 1841, and now it is said, one hundred thousand tuns could be made easily; while the annual product of iron from all the furnaces, which are said to be some three hundred in number, is estimated at over four hundred thousand tuns.
The yearly manufacture of iron in Great Britain, is now estimated at nearly three millions of tuns. In 1828, there were in Russia, nineteen founderies, forges and mines, and in 1804, that country exported to America over nine million pounds of iron. In 1819, France produced seventy-four million pounds of iron, and in 1845, this had increased to three hundred and forty-two millions, or over one hundred and fifty thousand tuns. Of ironand steel, and the various manufactures from them, Great Britain exported in 1845, to the extent of thirty-three millions.
Copper (fromcuprum, a corruption ofcuprium, from the island of Cyprus, whence it was formerly brought) was known at a very remote period; and in the early ages of the world, before iron was extensively in use, was the chief ingredient in domestic utensils and instruments of war. It is abundant; and is found both native and in many ores, the most important of which are the varieties ofpyrites, which are sulphurets of copper and iron. The genus copper includes some thirteen species, and each of these contains several varieties.
The purest copper obtained in Europe, is the produce of the mines of the Swedish province of Dalecarlia. The following is a brief description of the principal of these immense and gloomy caverns, all of which boast a high antiquity.
The traveler’s curiosity is first attracted by the hydraulic machines which convey the water to the different quarters, and the power of which is such, that one of the wheels has a diameter of not less than forty-four feet. Another wheel, of proportionate magnitude, is employed to raise the ore from the mine to the surface of the earth, and is admirably constructed. Regular circles are placed on each side, and round these the chain rises, taking a larger or smaller circumference, in proportion to the necessary circle to be made, so as to counterbalance the weight, and consequently the increased motion of the bucket.
Exteriorly, a vast chasm of a tremendous depth presents itself to the view. This being the part of the mine which was first opened, either through the ignorance or neglect of those who had then the management of the works, the excavations so weakened the foundations of the hill, that the whole fell in, leaving a most chaotic scene of precipitated rocks, and a gaping gulf resembling the mouth of a volcano. Great care has been since taken that no such disaster should again occur. Plans and sections are drawn of all the galleries, &c.; and where the prosecution of the works in the same direction might be dangerous, orders are issued for the miners to stop, and an iron crown is fixed on the spot, as a prohibition ever to proceed further. The workmen then explore in a different direction, while every subterraneous excavation is nicely watched.
The traveler passes into the great chasm by a range of wooden steps, which cross, in a variety of directions, the rough masses of fallen rocks, ofgravel, and of the ancient machinery. Ere he reaches the entrance of the cavern, he has to descend nearly two hundred feet, and this being accomplished, proceeds horizontally to a considerable distance within. He now loses the pure air of day, and gradually breathes an oppressive vapor, which rolls toward him, in volumes, from the mouths of a hundred caves leading into the main passage. He now feels as if he were inhaling the atmosphere of Tartarus. The Swedish iron mines which have been described, are mere purgatories when compared with this satanic dwelling. The descent is performed entirely by steps laid in the winding rock; and, in following the subterraneous declivity, the traveler reaches the tremendous depths of these truly Stygian dominions.
The pestilential vapors which environ him with increasing clouds, and the style of the entrance, remind him of Virgil’s description of the descent of Eneas to the infernal regions. Here are to be seen the same caverned portico, the rocky, rough descent, and the steaming sulphur, with all the deadly stenches of Avernus. The wretched inmates of this gloomy cavern, appear to him like so many specters, as poetic fiction has described them: and he is induced by the length of the way, joined to the excessive heat and its suffocating quality, to fancy that he will be made to pay dearly for his curiosity. In one part the steam is so excessively hot, as to scorch at the distance of twelve paces, at the same time that the sulphureous smell is intolerable. Near this spot a volcanic fire broke out some years ago, in consequence of which strong walls were constructed, as barriers to its power, and several contiguous passages, which, had it spread, would have proved dangerous to the mine, closed up.
The visitor has now to traverse many long and winding galleries, as well as large vaulted caverns, where the workmen are dispersed on all sides, employed in hewing vast masses of the rock, and preparing other parts for explosion. Others wheel the brazen ore toward the black abyss, where the suspended buckets hang ready to draw it upward. From the effect of such violent exercise, combined with the heat, they are obliged to work almost naked. Their groups, occupations, and primitive appearance, scantily lighted by the trembling rays of torches, form a curious and interesting scene.
The depth of the mine being at least twelve hundred feet, a full hour is required to reach to the bottom. The mass of copper lies in the form of an inverted cone. Five hundred men are employed daily; but females are not admitted, on account of the deleterious quality of the vapors. This mine was anciently a state prison, in which criminals, slaves and prisoners of war toiled out their wretched existence. Near the bottom is a rocky saloon,furnished with benches. It is called the Hall of the Senate, on account of its having been the resting-place of several Swedish kings, who came, attended by the senators, to examine the works, and here took refreshments. It was in this mine that the immortal Gustavus Vasa, disguised as a peasant, labored for his bread, during a long concealment, after having been robbed by his guide; and his first adherents in the struggle which placed him on the throne, were from the miners and peasants of Dalecarlia.
In the year 1751, a very rich copper mine was wrought in the county of Wicklow, Ireland. From this mine ran a stream of blue-colored water, of so deleterious a nature as to destroy all the fish in the river Arklow, into which it flowed. One of the workmen, having left an iron shovel in this stream, found it some days after incrusted with copper. This led one of the proprietors of the mine to institute a set of experiments, from which he concluded that the blue water contained an acid holding copper in solution; that iron had a stronger affinity for the acid than copper; and that the consequence of this affinity was the precipitation of the copper, and the solution of the iron, when pieces of that metal were thrown into the blue water. These ideas induced the miners to dig several pits for the reception of this water, and to put bars of iron into them. The result was, that they obtained an abundance of copper, much purer and more valuable than that which they had procured from the ore itself by smelting.
On the island of Anglesea, near Dulas bay, on the north coast, is Parys mountain, which contains the most considerable quantity of copper ore perhaps ever known. The external aspect of the hill is extremely rude, and it is surrounded by enormous rocks of coarse white quartz. The ore is lodged in a basin, or hollow, and has on one side a small lake, over the waves of which, as over those of Avernus, fatal to the feathered tribe, it is said that birds are never known to pass. The effect of the mineral operations has been, that the whole of this tract has assumed a wild and savage appearance. Suffocating fumes of the burning heaps of copper arise in all parts, and extend their baneful influence for miles around. That the ore was worked in a very remote period, appears by vestiges of the ancient operations, which were carried on by trenching, and by heating the rocks intensely, when water was suddenly poured on them, so as to cause them to crack or scale. In the year 1768, after a long search, which was so little profitable that it was on the eve of being abandoned, a large body of copper ore was found; and this has ever since been worked to great advantage, still promising a vast supply. The water lodged in the bottom of the bed of ore, being strongly impregnated with the metal, is drawn up and distributed in pits, where the same process is employed as in the Wicklow mine. Thecopper thus procured differs little from native copper, and is very highly prized.
In the Parys mine, eight tuns of gunpowder are annually expended in blasting the rock. Nature has here been profuse in bestowing her mineral favors; for, above the copper ore, and not more than two feet beneath the soil, is a bed of yellowish greasy clay, from three to twelve feet in thickness, containing lead ore, from a tun of which metal, upward of fifty ounces of silver are generally obtained.
COPPER MINE IN CORNWALL.
COPPER MINE IN CORNWALL.
COPPER MINE IN CORNWALL.
The copper mines of Cornwall, a view of one of which is given in the cut, are very numerous, and several of them large and very rich in ore. It is remarkable that in various parts of this country the earth has produced such an exuberance of this metal, as to afford it in large massy lumps of malleable copper, several pieces of which are shown in very curious vegetable forms. The particular ore namedmundic, found in the tin mines, was for many ages considered of no other use but to nourish that metal while in the mine. In the reign of Queen Elizabeth, a laudable curiosity tempted several private individuals to examine into its nature; but the design miscarried, and themundic was thrown, as useless, into the old pits in which the rubbish was collected. However, about a century ago, this purpose was effected by degrees; and the copper extracted from the ore now produces, on an average, upward of twelve thousand tuns, valued at between four and five millions of dollars, annually, equaling in goodness the best Swedish copper, while the ore itself yields a proportionate quantity oflapis calaminaris, for the making of brass.
At Ecton hill, near the river Dove, in Derbyshire, a valuable copper mine was discovered some years ago, and has since been worked to great advantage. In its position, situation and inclination, it differs from any mine yet discovered in Europe, Asia, Africa or America; the wonderful mass of copper ore not running in regular veins or courses, but sinking perpendicularly down, widening and swelling out at the bottom in the form of a bell. The works are four hundred and fifty feet beneath the river Dove, it being the deepest mine in Great Britain. On the opposite side of Ecton hill is a valuable lead mine, the veins of which approach very nearly to the copper mine.
Copper is converted into brass by the agency of calamine, an oxyd of zinc. It occurs frequently in beds, and in some places exists in great abundance. The Mendip hills, in Somersetshire, were once celebrated for their mines of calamine, which are now in a great measure exhausted. It is dug out of the earth, and being broken into small pieces, is exposed to the action of a current of water, which washes away the light earthy matter, and leaves the calamine. The whole is then thrown into deep wooden vessels filled with water, and agitated for a considerable time. The galena sinks to the bottom, the calamine is deposited in the center, and the earthy matter lies on the surface. The calamine, thus separated from its impurities, is ground to powder, and becomes fit for use.
Hungary abounds in valuable ores and minerals, and is most celebrated for its vast copper works, at a town called Herrengrund, built on the summit of a mountain, and exclusively inhabited by miners. Here the process, noticed above, of apparently converting iron into copper, is pursued with great success, several hundred weight of iron being thus transmuted every year. The vitriol, with which the blue water is strongly impregnated, can not be strictly said to convert the iron into copper, but insinuates into it the copper particles with which it is saturated; and this seeming transmutation requires a fortnight or three weeks only: but if the iron be suffered to lie too long in this vitriolic solution, it becomes at length reduced to powder.
In Japan, copper is the most common of all the metals, and is considered as the finest and most malleable anywhere to be found. Much of thiscopper is not only of the purest quality, but is blended with a considerable proportion of gold, which the Japanese separate and refine. The whole is brought to Saccin, one of the five principal cities of Japan; and it is there purified, and cast into small cylinders, about a span and a half in length, and a finger’s breadth in thickness. Brass is there very scarce, and much dearer than copper, the calamine employed in making it being imported from Tonquin in flat cakes, and sold at a very high price.
In addition to the copper mines thus described, copper has, within a few years, been found in the richest abundance in the vicinity of Lake Superior. The existence of copper there, was, indeed, known as early as 1636; and the trace of these early discoveries was never entirely lost. But the first scientific researches were made in 1842, by Dr. Douglas Houghton, who was acting as geological surveyor for the state of Michigan. According to his report, native copper exists in two or three different deposits about Lake Superior, where it is found in the richest abundance, both in veins and in large masses in the native state. Dr. Jackson also states, that he has seen one of these masses, twenty feet long, nine feet wide, and from four to six inches in thickness, and weighing about twenty tuns. He adds, that in a single year, thirty-three men, of whom only twenty were properly miners, had taken out forty-three tuns of ore, yielding thirty tuns of pure copper. Among the masses of copper obtained from these mines as early as 1848, were four, the weights of which, respectively, were seven thousand and eighteen, seven thousand four hundred and eighty-four, seven thousand six hundred and seventy-eight, and fourteen thousand pounds. Since that date new openings have been made; new mining companies formed, and the products of the mines very greatly increased: and it may yet be, that these mines will prove some of the richest and most valuable of the world.
Tin, in its pure state, has nearly the color and luster of silver. In hardness, it is midway between gold and lead. It was known to the ancients, who procured it from Spain and Britain, and appears to have been in use in the time of Moses. It is rather a scarce metal, being found in but few parts of the world in any considerable quantity. Cornwall is its most productive source; it also occurs in the mountains between Gallicia and Portugal, and in those between Saxony and Bohemia. It has, also, been brought from Malacca, in India, and from Chili and Mexico. There are but two ores of tin; one of which, the native peroxyd, is the chief source of all the suppliesof this metal, as the other ore, which is the double sulphuret of tin and copper, sometimes calledbell-metal ore, is extremely rare.
Cornwall has been in all ages, famous for its numerous mines of tin, which are in general very large, and rich in ore. The tin-works are of different kinds, dependent on the various forms in which the metal appears. In many places its ore so nearly resembles common stones, that it can only be distinguished from them by its superior weight. In other parts, the ore is a compound of tin and earth, concreted into a substance almost as hard as stone, of a bluish or grayish color, and to which the mundic, impregnated with copper, frequently gives a yellowish cast. This ore is always found in a continued stratum, which the miners call lode; and this, for the greater part, is found running through the solid substance of the hardest rocks, beginning in small veins near the surface, perhaps not above half an inch or an inch wide, and increasing, as they proceed, into large dimensions, branching out into several ramifications, and bending downward in a direction which is, generally, nearly east and west. These lodes, or veins, are sometimes white, very wide, and so thick, that large lumps of the ore are frequently drawn up of more than twenty pounds’ weight. The lodes of tin ore are not always contiguous, but sometimes break off so entirely, that they seem to terminate; but the sagacious miner knows by experience, that, by digging at a small distance on one side, he will meet with a separated part of the lode, apparently tallying with the other end, as nicely as if it had been broken off by some sudden shock of the rock.
The miners of Cornwall follow the lode, or vein, in all its rich and meandering curves through the bowels of the flinty earth. The waters are sometimes drained from the mines, by subterraneous passages, formed from the body of the mountain to the level country. These passages are calledadits, and are occasionally the labor of many years; but when effected, they save the constant expense of large water-works and fire-engines. From the surface of the earth the workmen sink a passage to the mine, which they call a shaft, and place over it a large winch, or, in works of greater magnitude, a wheel and axle, by which means they draw up large quantities of ore at a time, in vessels calledkibbuls. This ore is thrown into heaps, which great numbers of poor people are employed in breaking to pieces, and fitting the ore for the stamping-mills.
A third form in which tin appears is that of crystals; for this metal will, under proper circumstances, readily crystallize. Hence, in many parts of the mineral rocks, are found the most perfectly transparent and beautiful crystals of pure tin. Beside these crystals, in many of the cavernous parts of the rocks, are found those transparent crystals, called Cornish diamonds, theybeing extremely brilliant when well polished. The form is that of a six-sided prism pointed on the top, and they are sometimes four or five inches in length. The value of the tin exported from Great Britain, in 1853, the greater part of which came from the Cornwall mines, was nearly six million dollars.
Lead is one of the metals most anciently known, being mentioned in the books of Moses. It is found in some thirteen species of ore, only one of which (galena) occurs in masses sufficiently large to make it valuable as an object of mining and metallurgy. The uses of lead are so familiar that they need not be mentioned: they are known to all.
Among the most remarkable lead mines of the world, may be mentioned those of the state of Illinois, including also parts of Iowa and Wisconsin, which have been, and still are immensely productive, extending over thousands of acres, and furnishing the mineral in the richest abundance. These mines were formerly known as the mines of “Upper Louisiana.” They are now chiefly worked in the vicinity of Galena, a city which has sprung up, and is almost entirely supported by the trade in lead. So vast is the production of these mines, that forty million pounds of lead, valued at sixteen hundred thousand dollars, were shipped from Galena alone, in 1853. The mineral in one of the earliest opened mines, is said to be of two kinds, the gravel and fossil. The gravel mineral is found immediately under the soil, intermixed with gravel, in pieces of solid mineral weighing from one to fifty pounds. Beneath the gravel is a sand rock, which being broken, crumbles to a fine sand, and contains mineral nearly of the same quality as that of the gravel. But the mineral of the first quality is found in a bed of red clay, under the sand rock, in pieces of from ten to five hundred pounds’ weight, on the outside of which is a spar, or fossil, of a bright, glittering appearance, resembling spangles of gold and silver, as solid as the mineral itself, and of a greater specific gravity. This being taken off, the mineral is solid, unconnected with any other substance, of a broad grain, and what mineralogists call potters’ ore. In other mines, in the vicinity of the above, the lead is found in regular veins, from two to four feet in thickness, containing about fifty ounces of silver in a tun.
In Great Britain, there are numerous and exceedingly valuable lead mines, among which may be cited that of Arkingdale, in Yorkshire, and those with which Shropshire abounds. In the south of Lanarkshire, and in the vicinity of Wanlock-head, Scotland, are two celebrated lead mines, which yield annuallyabove two thousand tuns of metal. The Susannah-vein lead-hills, have been worked for many years, and have been productive of great wealth. The above are considered as the richest lead mines of Europe.
Several of the Irish lead mines have yielded a considerable proportion of silver; and mention is made of one, in the county of Antrim, which afforded, in thirty pounds of lead, a pound of that metal. Another, less productive of silver, was found at Ballysadare, near the harbor of Sligo, in Connaught; and a third in the county of Tipperary, thirty miles from Limerick. The ores of this last were of two kinds, most usually of a reddish color, hard and glittering; the other, which was the richest in silver, resembled a blue marl. The works were destroyed in the Irish insurrections in the reign of Charles I. The mine, however, is still wrought on account of the lead it contains.
Coal is one of the most valuable of all mineral treasures, and one that is of the highest service in making the others available to the use and comfort of man. And hence it has been searched after with unremitting diligence, and worked with all the lights of science and the resources of art. It is found in beds or strata, in that group of the secondary rocks which includes the red sandstone and mountain limestone formations, commonly called thecarboniferous group, or thecoal measures. From the peculiarities of their position, they are often spoken of ascoal-basins, andcoal-fields.
There are two or three points of some theoretical interest and importance as to the origin of coal, on which geological authorities are nearly unanimous. One is, that our present coal is exclusively of vegetable origin, formed apparently from the destruction of vast forests and immense quantities of leaves and shrubs; another, that it was formed when the climate of the regions where it is found was not merely tropical, but ultra-tropical, instead of being as now, temperate; and a third, that its deposits, though originally regular, have evidently been since elevated, and often singularly dislocated and contorted by forces acting from below, and probably of a volcanic nature. Each of these points will more or less appear in the progress of the following remarks.
That the coal formations are of vegetable origin, is perfectly evident from even a slight examination, especially with the microscope. Let a piece of coal be cut in very thin slices, or plates, and its appearance will be like that seen in the following cut. The vegetable fossils thus shown are, indeed, very different from any existing species, unless it be a few which are the productions only of torrid climates. And while the cut gives the appearance of butasingle leafin each specimen, the masses of coal are generally more like one thick imbedded mass of leaves, not so muchcrushed together, asoverlayingandmixed witheach other. According to Dr. Linley, the coal vegetation consisted of ferns, in great abundance; of large coniferous trees, of a species resemblinglycopodiacæ, but of most gigantic dimensions; of a numerous tribe apparently analogous tocactæ, but probably not identical with them; of palm, and othermonocotyledones; and finally, of numerous vines, plants, &c., the exact nature of which is uncertain. Whereleavesmost abound, the coal is said to be of the best quality; though as any one kind of coal hardens, the impressions of such leaves become gradually less distinct, until finally they can hardly be traced, even with a powerful magnifier. A hundred and twenty varieties of these vegetable impressions have been found in the vicinity of Pottsville, in the course of a few months, each as distinctly marked as the most delicate tracings of an artist’s pencil; and in almost any coal formation, there are so many hundreds of different plants, trees, and flowers, that a single representative of each kind would form a vast museum. Specimens which exhibit impressions of the bark, limbs, or trunks of trees, are, of course, correspondingly large and heavy, and could not easily be sketched in a small engraving, while the variety of leaves and flowers is so great, that it would be tedious to mention and describe them.
THIN PLATES OF COAL.
THIN PLATES OF COAL.
THIN PLATES OF COAL.
With these few remarks, we proceed to notice first, some of the coal mines of Great Britain, and then some of our own country. Perhaps there is no country where coal mines are so rich, so frequent, and so successfully worked thus far, as those of Great Britain; and it is to this cause that the opulence of that country has often been chiefly ascribed. It is, in truth, the coal of her mines, that is the very life of her manufactures, and consequently of her commerce, every manufacturing town being established in the midst of a coal country. Of this striking instances are afforded by Bristol, Birmingham, Wolverhampton, Sheffield, Newcastle, and Glasgow.
The coals of Whitehaven and Wigan are esteemed the purest; and the cannel and peacock coals of Lancashire are so beautiful, that they are suspected by some to have constituted thegagates, or jet, which the ancients ascribed to Great Britain. In Somersetshire, the Mendip coal mines are distinguished by their productiveness: they occur there, as indeed in every other part, in thelowcountry, and are not to be found in the hills. The beds of coal are not horizontal, but sloping, dipping to the south-east at the rate of about twenty-two inches per fathom. Hence they would speedily sink so deep that it would not be possible to work them, were it not that they are intersected at intervals by perpendicular dikes or veins, of a different kind of mineral, on the other side of which these beds are found considerably raised up. They are seven in number, lying at regular distances beneath each other, and separated by beds of a different kind of substance, the deepest being placed more than two hundred feet beneath the surface of the earth.
The town of Newcastle, in Northumberland, has been celebrated during several centuries for its very extensive trade in coal. It was first made a borough by William the Conqueror, and the earliest charter for digging coals, granted to the inhabitants, was in the reign of Henry III., in 1239; but in 1306, the use of coal for fuel was prohibited in London, by royal proclamation, chiefly because it injured the sale of wood, with which the environs of the capital were then overspread. This interdict did not, however, continue long in force; and coals may be considered as having been dug for exportation at Newcastle for more than four centuries. It has been estimated that there are twenty-four considerable collieries lying at different distances from the river, from five to eighteen miles; and that they produced, for an average of six years, up to the close of 1776, an annual consumption of three hundred and eighty thousand chaldrons, Newcastle measure, (equal to seven hundred and seventeen thousand, six hundred and fifteen chaldrons, London measure,) of which about thirty thousand chaldrons were exported to foreign parts. The boats employed in the colliery are calledkeels, and are described as strong, clumsy, and oval, each carrying about twenty tuns; and of these four hundred and fifty are kept constantly employed. In the year 1776 an estimate was made of the shipping employed in the Newcastle coal trade; and from this estimate it appears, that three thousand, five hundred and eighty-five ships, were during that year engaged in the coasting trade, and three hundred and sixty-three in the trade to foreign ports, their joint tunnage amounting to seven hundred and thirty-eight thousand, two hundred and fourteen tuns.
As already said, it is a common opinion among geologists, that coal is ofvegetable origin, and that it has been brought to its present state by the means of some chemical process, not at this time understood. This opinion is abundantly supported by the existence of vast depositions of matter, halfway, as it were, between perfect wood and perfect coal; which, while it obviously betrays its vegetable nature, has in several respects so near an approximation to coal, as to have been generally distinguished by the name of coal. One of the most remarkable of these depositions exists in Devonshire, about thirteen miles south-west of Exeter, and is well known under the name of Bovey coal. Its vegetable nature has been ascertained by Mr. Hatchet, in a set of experiments in which he found both extractive matter and resin, substances which belong to the vegetable kingdom.
The beds of this coal are seventy feet in thickness, and are interspersed with beds of clay. On the north side they lie within a foot of the surface, and dip south at the rate of about twenty inches per fathom. The deepest beds are the blackest and heaviest, and have the closest resemblance to coal, while the upper ones strongly resemble wood, and are considered as such by those who dig them. They are brown, and become extremely friable when dry, burning with a flame similar to that of wood, and assuming the appearance of wood which has been rendered soft by some unknown cause, and, while in that state, has been crushed flat by the weight of the incumbent earth. This is the case, not only with the Bovey coal, but also with all the beds of wood-coal which have been hitherto examined in different parts of Europe.[5]
5. We are informed by Liebig and other eminent chemists, that when wood and other vegetable matter are buried in the earth, exposed to moisture, and partially or entirely excluded from the air, they decompose slowly, and evolve carbonic acid gas; thus parting with a portion of their original oxygen. By this means they are gradually converted into lignite, or wood-coal, which contains a larger proportion of hydrogen than wood does. A continuance of decomposition changes this lignite into common or bituminous coal, chiefly by the discharge of carbureted hydrogen, or the gas by which we illuminate our streets and houses. According to Birchoff, the inflammable gases which are always escaping from mineral coal, and are so often the cause of fatal accidents in mines, always contain carbonic acid, carbureted hydrogen, nitrogen, and olefiant gas. The disengagement of all these gradually transforms ordinary or bituminous coal into anthracite, to which the various names of splint-coal, glance-coal, culm, and many others, have been given.
5. We are informed by Liebig and other eminent chemists, that when wood and other vegetable matter are buried in the earth, exposed to moisture, and partially or entirely excluded from the air, they decompose slowly, and evolve carbonic acid gas; thus parting with a portion of their original oxygen. By this means they are gradually converted into lignite, or wood-coal, which contains a larger proportion of hydrogen than wood does. A continuance of decomposition changes this lignite into common or bituminous coal, chiefly by the discharge of carbureted hydrogen, or the gas by which we illuminate our streets and houses. According to Birchoff, the inflammable gases which are always escaping from mineral coal, and are so often the cause of fatal accidents in mines, always contain carbonic acid, carbureted hydrogen, nitrogen, and olefiant gas. The disengagement of all these gradually transforms ordinary or bituminous coal into anthracite, to which the various names of splint-coal, glance-coal, culm, and many others, have been given.
The coal mines of Whitehaven may be considered as among the most extraordinary in the known world. They are excavations which have, in their structure, a considerable resemblance to the gypsum quarries of Paris, and are of such magnitude and extent, that in one of them alone, a sum exceeding half a million sterling, was, in the course of a century, expended by the proprietors. Their principal entrance is by an opening at the bottom of a hill, through a long passage hewn in the rock, leading to the lowest veinof coal. The greater part of this descent is through spacious galleries, which continually intersect other galleries, all the coal being cut away, with the exception of large pillars, which, where the mine runs to a considerable depth, are nine feet in hight, and about thirty-six feet square at the base. Such is the strength there required to support the ponderous roof.
The mines are sunk to the depth of one hundred and thirty fathoms, and are extended under the sea to places where there is, above them, sufficient depth of water for ships of large burden. These are the deepest coal mines which have hitherto been wrought; and perhaps the miners have not, in any other part of the globe, penetrated to so great a depth beneath the surface of the sea, the very deep mines in Hungary, Peru and elsewhere, being situated in mountainous countries, where the surface of the earth is elevated to a great hight above the level of the ocean.
In these mines there are three strata of coal, which lie at a considerable distance one above the other, and are made to communicate by pits; but the vein is not always continued in the same regularly inclined plane, the miners frequently meeting with hard rock, by which their further progress is interrupted. At such places there seem to have been breaks in the earth, from the surface downward, one portion appearing to have sunk down, while the adjoining part has preserved its ancient situation. In some of these places the earth has sunk ten, twenty fathoms, and even more; while in others the depression has been less than one fathom. These breaks the miners calldikes, and when they reach one of them, their first care is to discover whether the strata in the adjoining part are higher or lower than in the part where they have been working; or, according to their own phrase, whether the coal becast downorcast up. In the former case they sink a pit; but if it be cast up to any considerable hight, they are frequently obliged, with great labor and expense, to carry forward a level, or long gallery, through the rock, until they again reach the stratum of coal.
Coal, the chief mineral of Scotland, has been there worked for a succession of ages. Pope Pius II., in his description of Europe, written about 1450, mentions that he beheld with wonder black stones given as alms to the poor of Scotland. This mineral may, however, be traced to the twelfth century; and a very early account of the Scottish coal mines, explains with great precision, the manner of working the coal, not neglecting to mention the subterraneous walls ofwhinwhich intersect the strata, particularly a remarkable one, visible from the river Tyne, where it forms a cataract, and passes by Prestonpans, to the shore of Fife. The Lothians and Fifeshire, particularly abound with this useful mineral, which also extends into Ayrshire; and near Irwin is found a curious variety, named ribbon-coal. Asingular coal, in veins of mineral, has been found at Castle Leod, in the east of Ross-shire; and it is conjectured that the largest untouched field of coal in Europe, exists in a barren tract of country in Lanarkshire.
The process of mining coal is a combination of boring and digging. Shafts are sunk, levels are driven, and drains are carried off, by the help of picks or pickaxes, wedges and hammers, the rocks being also sometimes loosened by blasting with gunpowder. In searching for coal, a shaft is sunk through the uppermost soft stratum, and the rock is then bored, by striking it continually with an iron borer terminating in an edge of steel, which is in the mean time turned partly round; and, at proper intervals, a scoop is let down to draw up the loose fragments. In this manner a perforation is sometimes made for more than an hundred fathoms, the borer being lengthened by pieces screwed on; it is then partly supported by a counterpoise, and worked by machinery. Should it happen to break, the piece is raised by a rod furnished with a hollow cone, as an extinguisher, which is driven down on it. The borer is sometimes furnished with knives, which are made to act on any part at pleasure, and to scrape off a portion of the surrounding substance, which is collected in a proper receptacle.
Those who have the direction of deep and extensive coal mines, are obliged, with great art and care, to keep them ventilated with perpetual currents of fresh air, which afford the miners a constant supply of that vital fluid, and expel from the mines damps and other noxious exhalations, together with such other burnt and foul air, as has become deleterious and unfit for respiration. In the deserted mines, which are not thus ventilated with currents of fresh air, large quantities of these damps are frequently collected; and in such works they often remain for a long time without doing any mischief. But when, by some accident, they are set on fire, they then produce dreadful explosions, and, bursting out of the pits with great impetuosity, like the fiery eruptions from burning mountains, force along with them ponderous bodies to a great hight in the air.
Various instances have occurred in which the coal has been set on fire by the fulminating damp, and has continued burning for several months, until large streams of water were conducted into the mine, so as to inundate the parts where the conflagration existed. By such fires several collieries have been entirely destroyed, in the vicinity of Newcastle, and in other parts of England, as well as in Fifeshire, in Scotland. In some of these places the fire has continued to burn for ages. To prevent, therefore, as much as possible, the collieries from being filled with these pernicious damps, it has been found necessary carefully to search for the crevices in the coal whence they issue, and, at those places, to confine them within a narrow space, conductingthem through large pipes into the open air, where, being set on fire, they consume in perpetual flame as they continually arise out of the earth.
Mr. Spelling, an engineer of the Whitehaven coal mines, having observed that the fulminating damp could only be kindled by flame, and that it was not liable to be set on fire by red-hot iron, nor by the sparks produced by the collision of flint and steel, invented a machine called a steel-mill, in which a wheel of that metal is turned round with a very rapid motion, and, by the application of flints, great plenty of sparks are emitted, which afford the miners such a light as enables them to carry on their work in close places, where the flame of a candle, or a lamp, would, as has already happened in various instances, occasion violent explosions. In that dreadful catastrophe, the explosion of the Felling colliery, the particulars of which will be hereafter detailed, it will be seen that mills of this description were employed, in searching for the remains of the victims of the sad disaster; but this event happened before the invention of Sir Humphrey Davy’s safety-lamp, a discovery which, while it affords a more certain light, holds out every security to the miner against accidents which, without such a resource, might still be superadded to those already recorded, as arising from the flame of a candle or lamp.
A greater number of mines have, however, been ruined by inundations than by fires; and here that noble invention, the fire-engine, displays its beneficial effects. It appears from nice calculations, that it would require about five hundred and fifty men, or a power equal to that of one hundred and ten horses, to work the pumps of one of the largest fire-engines, having a cylinder seventy inches in diameter, now in use, and thrice that number of men to keep an engine of that size constantly at work. It also appears that as much water may be raised by such an engine, as can be drawn, within the same space of time, by twenty-five hundred and twenty men with rollers and buckets, after the manner long practiced in many mines; or as much as can be borne on the shoulders of twice that number of men, as is said to be done in several of the mines of Peru. So great is the power of the elastic steam of the boiling water in those engines, and of the outward atmosphere, which, by their alternate actions give force and motion to the beam, and through it to the pump rods which elevate the water through tubes, and discharge it from the mine!
Years since there were four fire-engines belonging to the Whitehaven colliery, which when all at work, discharged from it about twelve hundred and twenty-eight gallons of water every minute, at thirteen strokes; and at the same rate, one million, seven hundred and sixty-eight thousand, three hundred and twenty gallons, upward of seven thousand tuns, every twenty-fourhours. By these engines nearly twice the above-mentioned quantity of water might be discharged from mines not more than sixty or seventy fathoms deep, which depth is rarely exceeded in the Newcastle collieries, or in any other English collieries, with the exception of the above.
Coal pits have sometimes taken fire by accident, and have continued to burn for a considerable length of time. About the year 1648, a coal mine at Benwell, a village near Newcastle-upon-Tyne, was accidentally kindled by a candle: at first the fire was so feeble, that a reward of half a crown, which was asked by a person who offered to extinguish it, was refused. It gradually increased, however, and had continued burning for thirty years, when the account was drawn up and published in the Philosophical Transactions: it was not finally extinguished until all the fuel was consumed. Examples of a similar kind have happened in Scotland and in Germany.
But of all the recorded accidents relative to coal mines, that of Felling colliery, near Sunderland, a concise narrative of which here follows, was the most disastrous.
Felling is a manor about a mile and a half east of Gateshead. It contains several strata of coal, the uppermost of which were extensively wrought in the beginning of the last century. The stratum called the high-main, was begun in 1779, and continued to be wrought till the nineteenth of January, 1811, when it was entirely excavated. The present colliery was in the seam called the low-main. It commenced in October, 1810, and was at full work in May, 1812. This mine was considered by the workmen as a model of perfection in the purity of its air, and orderly arrangements; its inclined plane was saving the daily expense of at least thirteen horses; the concern wore the features of the greatest possible prosperity, and no accident, except a trifling explosion of fire-damp, slightly burning two or three workmen, had occurred. Twoshifts, or sets of men, were constantly employed, except on Sundays. Twenty-five acres of coal had been excavated. The first shift entered the mine at four o’clock, A. M., and were relieved at their working-posts by the next at eleven o’clock in the morning. The establishment employed under ground, consisted of about one hundred and twenty-eight persons, who, from the eleventh to the twenty-fifth of May, 1812, wrought six hundred and twenty-four scores of coal, equal to thirteen hundred Newcastle, or twenty-four hundred and fifty-five London chaldrons.
About half past eleven o’clock, on the morning of the twenty-fifth of May, 1812, the neighboring villages were alarmed by a tremendous explosion in this colliery. The subterraneous fire broke forth with two heavy discharges from the low-main, which were almost instantaneously followed by one from the high-main. A slight trembling, as from an earthquake, was felt forabout half a mile around the workings; and the noise of the explosion, though dull, was heard to three or four miles’ distance, and much resembled an unsteady fire of infantry. Immense quantities of dust and small coal accompanied these blasts, and rose high into the air, in the form of an inverted cone. The heaviest part of the ejected matter, such as corves, pieces of wood, and small coal, fell near the pits; but the dust, borne away by a strong west wind, fell in a continued shower from the pit to the distance of a mile and a half. As soon as the explosion was heard, the wives and children of the workmen ran to the pit; the scene was distressing beyond the power of description.
Of one hundred and twenty-eight persons in the mine at the time of the explosion, only thirty-two were brought to daylight: twenty-nine survived the fatal combustion; the rest were destroyed. Nor from the time of the explosion till the eighth of July, could any person descend. But after many unsuccessful attempts to explore the burning mine, it was reclosed, to prevent the atmospheric air from entering it: this being done, no attempt was afterward made to explore it, till the morning of the last-mentioned day; from which time to the nineteenth of September, the heart-rending scene of mothers and widows examining the putrid bodies of their sons and husbands, for marks by which to identify them, was almost daily renewed; but very few of them were known by any personal mark; they were too much mangled and scorched to retain any of their features. Their clothes, tobacco-boxes, shoes, &c., were, therefore, the only indexes by which they could be recognized.
At the crane twenty-one bodies lay in ghastly confusion: some like mummies, scorched as dry as if they were baked. One wanted its head, another an arm. The scene was truly frightful. The power of fire was visible upon them all; but its effects were extremely variable: while some were almost torn to pieces, there were others who appeared as if they had sunk down overpowered with sleep. The ventilation concluded on Saturday the nineteenth of September, when the ninety-first body was dug from under a heap of stones. At six o’clock in the morning the pit was visited by candle-light, which had not been used in it for the space of one hundred and seventeen days; and at eleven o’clock in the morning the tube furnace was lighted. From this time the colliery has been regularly at work; but the ninety-second body has never yet been found. All these persons, except four, who were buried in single graves, were interred in Heworth chapel-yard, in a trench, side by side, two coffins deep, with a partition of brick and lime between every four coffins.
Having thus glanced at some of the coal mines of Great Britain, we nowpass to some of those of the United States. In these coal is found infourdifferent forms:first, thegenuineanthracite, orglancecoal, as near Worcester, Mass., and Newport, R. I.;second, coal destitute of bitumen, commonly called anthracite, but which is more properly anasphaltic, which is found at Pottsville, Mauch Chunk, Lackawanna, Wilkesbarre, &c.;third, bituminous coal, usually found in the slate rock, as at Tioga, Lycoming, etc.; andfourth, the lignite coal, found along the south shore of the bay of South Amboy, New Jersey. From the state of Alabama to Pictou, Nova Scotia, the coal beds can be followed in a north-east direction, for fifteen hundred miles; and from Richmond, in Virginia, to Rock River, in Illinois, they are continually crossed at right angles, for about eight hundred miles. At Richmond, the coal is bituminous; on the Alleghany belt, it is anthracite. Geologists think that the anthracite was lifted out of its horizontal position when the great Alleghany belt was upheaved, and that its non-bituminous quality is owing to the influence of the intense heat that accompanied its upheaval.
Taylor, in his book on coal, estimates the area of bituminous coal in the United States, east of the Mississippi river, at one hundred and twenty-four thousand, seven hundred and thirty-five square miles, and west of the Mississippi, at eight thousand, three hundred and ninety-seven square miles; British North America, eighteen thousand square miles bituminous. More than one-third of the area of Pennsylvania, is more or less marked by coal formations; one-third of Kentucky, Ohio and Virginia, one-fifth of Indiana, and three-fourths of Illinois, are occupied by carboniferous strata. Western Pennsylvania abounds in bituminous coal, and it is found also in several counties of New York. By the census of 1839-40, we find that the quantity of bituminous coal produced that year in the United States, was twenty-seven million, six hundred and three thousand, one hundred and ninety-one bushels, employing about four thousand men, and a capital of some two million dollars; and that about four million dollars of capital were invested in raising anthracite coal, of which some nine hundred thousand tuns (of about twenty-eight bushels each) were produced by the labors of about three thousand men. Most of this was from Pennsylvania.
In 1819, the anthracite coal trade had no existence; in 1820, this kind of coal was first used as fuel, and just three hundred and sixty-five tuns were sent to market; in 1845, the amount was two million tuns; in 1850, about three million, five hundred thousand tuns, and the present year (1854) the amount will probably be between six and seven million tuns. The demand and supply so steadily and rapidly increase that it is impossible to estimate the vast extent the business of coal mining is yet to attain.
Glancing for a moment at other countries, we find that Belgium, in 1845, had two hundred and twelve mines, employing thirty-eight thousand miners and five hundred steam-engines, and producing five million tuns; France, four hundred and forty-nine mines, employing thirty thousand miners, and producing five million tuns; Prussia, in 1840, seven hundred and fifty-two mines, employing twenty-four thousand miners, and raising three million, five hundred thousand tuns; and that Great Britain, in 1846, produced thirty-five million tuns, valued at forty-five million dollars at the mines. Austria and Spain, also, have excellent mines, though less productive. And as a late and interesting discovery, it may be added, that the recent Arctic expedition sent out from England, found coal in those northern regions, on the island of Disco, outcropping near the shore. They also, in another locality not far off, discovered some curious specimens of petrified trees, and near them extensive quarries of anthracite coal, of good quality. There appeared to be no limit to the quantity that might be thrown into a boat with ease, and in the space of three hours they conveyed not less than twelve tuns to the steamer, three-quarters of a mile distant. It proved, on trial, to be of good quality, the combustion was perfect, and the coal as economical as the Welsh.
We will conclude the subject of coal mines, with the statement of a recent tourist, as to some of the wonders of the Cornish mines in England, as he saw them in 1854. He says: “Some of the mines are truly grand undertakings. The’the largest of the Cornish group, employ upward of three thousand persons. One of the engines pumps water from a direct depth of sixteen hundred feet, the weight of the pumping apparatus alone being upward of five hundred tuns; the pumping-rod is one thousand, seven hundred and forty feet long, and it raises about two million gallons of water in a week, from a depth equal to five times the hight of St. Paul’s. These are, indeed, wonders to marvel at! The consolidated and united mines, both belonging to one company, are stated to have used the following vast quantities of materials in a year: coals, fifteen thousand, two hundred and seventy tuns; candles, one hundred and thirty-two thousand, one hundred and forty-four pounds; gunpowder, eighty-two thousand pounds; leather, for straps, &c., thirteen thousand, four hundred and ninety-three pounds; pick and shovel handles, sixteen thousand, six hundred and ninety-eight dozens. Sir Charles Lemon has estimated, that in the whole of the Cornish mines, thirteen thousand pounds’ worth of gunpowder is used annually; that the timber employed in the underground works, equals the growth of one hundred and forty square miles of Norwegian forest; and that thirty-seven million tuns of water are raised annually from the mines.”