Though the mineral resources of Spain are immense, yet its iron-industry is so little developed that more than two-thirds of the excellent ores of Biscay, instead of being smelted in the country, are exported to France and England.
In Italy the red oxide and magnetic iron-stone mines of Elba have been celebrated since the remotest antiquity, but, from the want of fuel on the island, their entire produce, which amounts to about 100,000 tons, is exported to the coast of Italy, to France, and to England. The principal mines are situated on the slope of a steep mountain fronting the sea, and are divided by horizontal terraces into five stories or huge steps communicating with each other by means of oblique roads, on which carts convey the ores to the shore. Though worked for more than 2,000 years, the mines, which occupy about 700 workmen, are apparently able to supply the wants of the remotest posterity.
On turning to America we find the United States making gigantic strides in the extension of their iron manufacture, which has risen from 347,000 tons in 1840 to 1,200,000 tons in 1864; and as here none of the elements of progress are wanting—a boundless mineral wealth, liberal institutions, which allow the freest scope to individual energy, and an unrivalled spirit of enterprise—there can hardly be a doubt that finally the United States must become the first iron-country in the world. The masses of magnetic iron-stone and red oxide which extend along Lake Superior, over a length of 120 miles and a breadth of from five to thirty, would alone suffice to provide for the wants of the whole of the human race for many thousands of years. They only began to be worked in 1849; and in 1866 the railroad which leads from the mines transported 204,454 tons of ore.
The thriving town of Marquette, the central point of this new seat of industry, was, scarcely twenty years ago, a complete wilderness, where the Red Indian pursued the beasts of the forest, unconscious that the treasures concealed beneath his natal soil would one day be the cause of his expulsion from the hunting-grounds of his fathers.
The State of Missouri possesses two ‘iron-mountains’ similar to the magnetic mountain of the Demidoff: one of them called Pilot Knob is 600 feet high, the other 220. An immense mass of magnetic oxide has also been discovered in California, near the northern extremity of the Sierra Nevada. But though iron is found in abundance in many parts of the Union, (Tennessee, North and South Carolina, Georgia, &c.), the States of New York and Pennsylvania produce by far the greatest quantity.
Brazil and the island of Cuba likewise contain vast deposits of the richest iron-ores; and in Mexico we find the famous Cerro del Mercado, an iron-mountain 633 feet high, which rises in grotesque form from the valley of Durango. This wonderful mound has been calculated to contain 3,244,000,000 cubic feet, or 454,000,000 tons, of magnetic iron ore, capable of yielding 290,000,000 tons of cast iron, or more than fifty times the annual production of Great Britain! A more industrious and civilised race would here find a boundless field for profitable employment; but the indolent Mexican, steeped in ignorance and falling from one revolution into another, still leaves these treasures almost untouched, and, neglecting the vast resources of his country, draws nearly his whole supply of iron from the distant forges of Great Britain.
CHAPTER XXIX.
LEAD.
Its Properties and extensive Uses—Alston Moor—Belgian Lead Mines—Galena in America—Extraction of Silver from Lead Ores—Pattinson’s Process—A great part of our wealth is due to the laboratory.
Lead was but little prized by the ancients, who, unacquainted with gunpowder, needed no bullets for war or for the chase. The history of its first discovery is lost in obscurity, but it probably became known much later than copper or tin, as less metallurgic skill is required for the smelting of the cupreous or stanniferous ores than for the reduction of galena or sulphide of lead, which is the most abundant of the plumbiferous ores, and may indeed be regarded as the only commercial ore of any value, if we except the carbonates, which are probably formed by its decomposition.
Lead, however, is mentioned both in the Book of Job and in the fourth book of Moses, ‘Oh! that my words were graven with an iron pen on tablets of lead,’ exclaims the long-suffering patriarch, and the legislator of the Jews commands his people to ‘make go through the fire, gold, silver, brass, tin, and lead, and everything that may abide it.’ The Phœnicians, who provided Greece and Egypt with Spanish lead, frequently made use of this metal to increase the weight of their anchors; and Herodotus, describing a bridge in Babylon, mentions that its stones were fastened with clasps of iron soldered with lead. The physical properties of this metal qualify it for a great variety of uses. As it is but little altered by exposure to air or water, it makes excellent pump-tubes and rain-gutters; while its considerable weight, its softness, its flexibility, and the facility with which it melts at a comparatively low temperature render it an invaluable material for the soldier’s bullet or the huntsman’s shot. Combined with oxygen it forms the pigment called red-lead, or minium, and united with carbonic acid white-lead, or ceruse, which is still more frequently used in painting.